diff --git "a/vtt/episode_035_small.vtt" "b/vtt/episode_035_small.vtt" new file mode 100644--- /dev/null +++ "b/vtt/episode_035_small.vtt" @@ -0,0 +1,6443 @@ +WEBVTT + +00:00.000 --> 00:03.120 + The following is a conversation with Jeremy Howard. + +00:03.120 --> 00:07.080 + He's the founder of Fast AI, a research institute dedicated + +00:07.080 --> 00:09.760 + to making deep learning more accessible. + +00:09.760 --> 00:12.560 + He's also a distinguished research scientist + +00:12.560 --> 00:14.600 + at the University of San Francisco, + +00:14.600 --> 00:17.600 + a former president of Kegel, as well as a top breaking + +00:17.600 --> 00:18.800 + competitor there. + +00:18.800 --> 00:21.680 + And in general, he's a successful entrepreneur, + +00:21.680 --> 00:25.240 + educator, researcher, and an inspiring personality + +00:25.240 --> 00:27.000 + in the AI community. + +00:27.000 --> 00:28.680 + When someone asked me, how do I get + +00:28.680 --> 00:30.240 + started with deep learning? + +00:30.240 --> 00:33.360 + Fast AI is one of the top places I point them to. + +00:33.360 --> 00:34.120 + It's free. + +00:34.120 --> 00:35.520 + It's easy to get started. + +00:35.520 --> 00:37.600 + It's insightful and accessible. + +00:37.600 --> 00:40.960 + And if I may say so, it has very little BS. + +00:40.960 --> 00:44.160 + It can sometimes dilute the value of educational content + +00:44.160 --> 00:46.720 + on popular topics like deep learning. + +00:46.720 --> 00:49.440 + Fast AI has a focus on practical application + +00:49.440 --> 00:51.600 + of deep learning and hands on exploration + +00:51.600 --> 00:53.880 + of the cutting edge that is incredibly + +00:53.880 --> 00:57.960 + both accessible to beginners and useful to experts. + +00:57.960 --> 01:01.360 + This is the Artificial Intelligence Podcast. + +01:01.360 --> 01:03.760 + If you enjoy it, subscribe on YouTube, + +01:03.760 --> 01:06.920 + give it five stars on iTunes, support it on Patreon, + +01:06.920 --> 01:09.040 + or simply connect with me on Twitter. + +01:09.040 --> 01:13.280 + Alex Friedman, spelled F R I D M A N. + +01:13.280 --> 01:18.560 + And now, here's my conversation with Jeremy Howard. + +01:18.560 --> 01:21.680 + What's the first program you ever written? + +01:21.680 --> 01:24.800 + First program I wrote that I remember + +01:24.800 --> 01:29.200 + would be at high school. + +01:29.200 --> 01:31.240 + I did an assignment where I decided + +01:31.240 --> 01:36.240 + to try to find out if there were some better musical scales + +01:36.240 --> 01:40.640 + than the normal 12 tone, 12 interval scale. + +01:40.640 --> 01:43.680 + So I wrote a program on my Commodore 64 in BASIC + +01:43.680 --> 01:46.080 + that searched through other scale sizes + +01:46.080 --> 01:48.440 + to see if it could find one where there + +01:48.440 --> 01:51.880 + were more accurate harmonies. + +01:51.880 --> 01:53.040 + Like mid tone? + +01:53.040 --> 01:56.520 + Like you want an actual exactly 3 to 2 ratio, + +01:56.520 --> 01:59.400 + where else with a 12 interval scale, + +01:59.400 --> 02:01.480 + it's not exactly 3 to 2, for example. + +02:01.480 --> 02:05.080 + So that's well tempered, as they say. + +02:05.080 --> 02:07.680 + And BASIC on a Commodore 64. + +02:07.680 --> 02:09.440 + Where was the interest in music from? + +02:09.440 --> 02:10.480 + Or is it just technical? + +02:10.480 --> 02:14.640 + I did music all my life, so I played saxophone and clarinet + +02:14.640 --> 02:18.120 + and piano and guitar and drums and whatever. + +02:18.120 --> 02:22.200 + How does that thread go through your life? + +02:22.200 --> 02:24.160 + Where's music today? + +02:24.160 --> 02:28.320 + It's not where I wish it was. + +02:28.320 --> 02:30.200 + For various reasons, couldn't really keep it going, + +02:30.200 --> 02:32.560 + particularly because I had a lot of problems with RSI, + +02:32.560 --> 02:33.480 + with my fingers. + +02:33.480 --> 02:37.360 + And so I had to cut back anything that used hands + +02:37.360 --> 02:39.360 + and fingers. + +02:39.360 --> 02:43.920 + I hope one day I'll be able to get back to it health wise. + +02:43.920 --> 02:46.240 + So there's a love for music underlying it all. + +02:46.240 --> 02:47.840 + Sure, yeah. + +02:47.840 --> 02:49.480 + What's your favorite instrument? + +02:49.480 --> 02:50.360 + Saxophone. + +02:50.360 --> 02:51.000 + Sax. + +02:51.000 --> 02:52.840 + Baritone saxophone. + +02:52.840 --> 02:57.440 + Well, probably bass saxophone, but they're awkward. + +02:57.440 --> 03:00.120 + Well, I always love it when music is + +03:00.120 --> 03:01.760 + coupled with programming. + +03:01.760 --> 03:03.800 + There's something about a brain that + +03:03.800 --> 03:07.520 + utilizes those that emerges with creative ideas. + +03:07.520 --> 03:11.200 + So you've used and studied quite a few programming languages. + +03:11.200 --> 03:15.120 + Can you give an overview of what you've used? + +03:15.120 --> 03:17.920 + What are the pros and cons of each? + +03:17.920 --> 03:21.960 + Well, my favorite programming environment almost certainly + +03:21.960 --> 03:26.520 + was Microsoft Access back in the earliest days. + +03:26.520 --> 03:29.080 + So that was a special basic for applications, which + +03:29.080 --> 03:30.720 + is not a good programming language, + +03:30.720 --> 03:33.080 + but the programming environment is fantastic. + +03:33.080 --> 03:40.120 + It's like the ability to create user interfaces and tied data + +03:40.120 --> 03:43.720 + and actions to them and create reports and all that. + +03:43.720 --> 03:46.800 + As I've never seen anything as good. + +03:46.800 --> 03:48.920 + So things nowadays like Airtable, which + +03:48.920 --> 03:56.200 + are like small subsets of that, which people love for good reason. + +03:56.200 --> 04:01.160 + But unfortunately, nobody's ever achieved anything like that. + +04:01.160 --> 04:03.320 + What is that, if you could pause on that for a second? + +04:03.320 --> 04:03.840 + Oh, Access. + +04:03.840 --> 04:04.340 + Access. + +04:04.340 --> 04:06.320 + Is it a fundamental database? + +04:06.320 --> 04:09.600 + It was a database program that Microsoft produced, + +04:09.600 --> 04:13.440 + part of Office, and it kind of withered. + +04:13.440 --> 04:16.320 + But basically, it lets you in a totally graphical way + +04:16.320 --> 04:18.480 + create tables and relationships and queries + +04:18.480 --> 04:24.720 + and tie them to forms and set up event handlers and calculations. + +04:24.720 --> 04:28.680 + And it was a very complete, powerful system designed + +04:28.680 --> 04:35.000 + for not massive scalable things, but for useful little applications + +04:35.000 --> 04:36.400 + that I loved. + +04:36.400 --> 04:40.240 + So what's the connection between Excel and Access? + +04:40.240 --> 04:42.160 + So very close. + +04:42.160 --> 04:47.680 + So Access was the relational database equivalent, + +04:47.680 --> 04:48.360 + if you like. + +04:48.360 --> 04:51.080 + So people still do a lot of that stuff + +04:51.080 --> 04:54.120 + that should be in Access in Excel because they know it. + +04:54.120 --> 04:56.680 + Excel's great as well. + +04:56.680 --> 05:01.760 + But it's just not as rich a programming model as VBA + +05:01.760 --> 05:04.680 + combined with a relational database. + +05:04.680 --> 05:07.320 + And so I've always loved relational databases. + +05:07.320 --> 05:11.080 + But today, programming on top of relational databases + +05:11.080 --> 05:13.840 + is just a lot more of a headache. + +05:13.840 --> 05:16.680 + You generally either need to kind of, + +05:16.680 --> 05:19.040 + you need something that connects, that runs some kind + +05:19.040 --> 05:21.560 + of database server, unless you use SQLite, which + +05:21.560 --> 05:25.000 + has its own issues. + +05:25.000 --> 05:26.320 + Then you kind of often, if you want + +05:26.320 --> 05:27.760 + to get a nice programming model, you + +05:27.760 --> 05:30.440 + need to create an ORM on top. + +05:30.440 --> 05:34.360 + And then, I don't know, there's all these pieces tied together. + +05:34.360 --> 05:37.000 + And it's just a lot more awkward than it should be. + +05:37.000 --> 05:39.200 + There are people that are trying to make it easier, + +05:39.200 --> 05:44.480 + so in particular, I think of Fsharp, Don Syme, who him + +05:44.480 --> 05:49.320 + and his team have done a great job of making something + +05:49.320 --> 05:51.640 + like a database appear in the type system, + +05:51.640 --> 05:54.960 + so you actually get tab completion for fields and tables + +05:54.960 --> 05:57.840 + and stuff like that. + +05:57.840 --> 05:59.280 + Anyway, so that was kind of, anyway, + +05:59.280 --> 06:01.880 + so that whole VBA Office thing, I guess, + +06:01.880 --> 06:04.560 + was a starting point, which is your miss. + +06:04.560 --> 06:07.800 + And I got into Standard Visual Basic, which + +06:07.800 --> 06:09.840 + that's interesting, just to pause on that for a second. + +06:09.840 --> 06:12.600 + And it's interesting that you're connecting programming + +06:12.600 --> 06:18.200 + languages to the ease of management of data. + +06:18.200 --> 06:20.600 + So in your use of programming languages, + +06:20.600 --> 06:24.880 + you always had a love and a connection with data. + +06:24.880 --> 06:28.640 + I've always been interested in doing useful things for myself + +06:28.640 --> 06:31.880 + and for others, which generally means getting some data + +06:31.880 --> 06:34.600 + and doing something with it and putting it out there again. + +06:34.600 --> 06:38.400 + So that's been my interest throughout. + +06:38.400 --> 06:41.560 + So I also did a lot of stuff with Apple script + +06:41.560 --> 06:43.880 + back in the early days. + +06:43.880 --> 06:47.960 + So it's kind of nice being able to get the computer + +06:47.960 --> 06:52.960 + and computers to talk to each other and to do things for you. + +06:52.960 --> 06:56.600 + And then I think that one night, the programming language + +06:56.600 --> 06:59.960 + I most loved then would have been Delphi, which + +06:59.960 --> 07:05.960 + was Object Pascal created by Anders Halsberg, who previously + +07:05.960 --> 07:08.840 + did Turbo Pascal and then went on to create.net + +07:08.840 --> 07:11.080 + and then went on to create TypeScript. + +07:11.080 --> 07:16.720 + Delphi was amazing because it was like a compiled, fast language + +07:16.720 --> 07:20.200 + that was as easy to use as Visual Basic. + +07:20.200 --> 07:27.480 + Delphi, what is it similar to in more modern languages? + +07:27.480 --> 07:28.840 + Visual Basic. + +07:28.840 --> 07:29.680 + Visual Basic. + +07:29.680 --> 07:32.320 + Yeah, that a compiled, fast version. + +07:32.320 --> 07:37.080 + So I'm not sure there's anything quite like it anymore. + +07:37.080 --> 07:42.520 + If you took C Sharp or Java and got rid of the virtual machine + +07:42.520 --> 07:45.040 + and replaced it with something, you could compile a small type + +07:45.040 --> 07:46.520 + binary. + +07:46.520 --> 07:51.680 + I feel like it's where Swift could get to with the new Swift + +07:51.680 --> 07:56.640 + UI and the cross platform development going on. + +07:56.640 --> 08:01.600 + That's one of my dreams is that we'll hopefully get back + +08:01.600 --> 08:02.840 + to where Delphi was. + +08:02.840 --> 08:08.520 + There is actually a free Pascal project nowadays + +08:08.520 --> 08:10.320 + called Lazarus, which is also attempting + +08:10.320 --> 08:13.960 + to recreate Delphi. + +08:13.960 --> 08:16.080 + They're making good progress. + +08:16.080 --> 08:21.000 + So OK, Delphi, that's one of your favorite programming languages? + +08:21.000 --> 08:22.360 + Well, it's programming environments. + +08:22.360 --> 08:26.280 + Again, say Pascal's not a nice language. + +08:26.280 --> 08:27.880 + If you wanted to know specifically + +08:27.880 --> 08:30.360 + about what languages I like, I would definitely + +08:30.360 --> 08:35.480 + pick Jay as being an amazingly wonderful language. + +08:35.480 --> 08:37.000 + What's Jay? + +08:37.000 --> 08:39.600 + Jay, are you aware of APL? + +08:39.600 --> 08:43.520 + I am not, except from doing a little research on the work + +08:43.520 --> 08:44.080 + you've done. + +08:44.080 --> 08:47.280 + OK, so not at all surprising you're not + +08:47.280 --> 08:49.040 + familiar with it because it's not well known, + +08:49.040 --> 08:55.480 + but it's actually one of the main families of programming + +08:55.480 --> 08:57.920 + languages going back to the late 50s, early 60s. + +08:57.920 --> 09:01.720 + So there was a couple of major directions. + +09:01.720 --> 09:04.440 + One was the kind of lambda, calculus, + +09:04.440 --> 09:08.640 + Alonzo church direction, which I guess kind of Lisbon scheme + +09:08.640 --> 09:12.040 + and whatever, which has a history going back + +09:12.040 --> 09:13.440 + to the early days of computing. + +09:13.440 --> 09:17.360 + The second was the kind of imperative slash + +09:17.360 --> 09:23.240 + OO, algo, similar going on to C, C++, so forth. + +09:23.240 --> 09:26.960 + There was a third, which are called array oriented languages, + +09:26.960 --> 09:31.720 + which started with a paper by a guy called Ken Iverson, which + +09:31.720 --> 09:37.480 + was actually a math theory paper, not a programming paper. + +09:37.480 --> 09:41.520 + It was called Notation as a Tool for Thought. + +09:41.520 --> 09:45.320 + And it was the development of a new type of math notation. + +09:45.320 --> 09:48.560 + And the idea is that this math notation was much more + +09:48.560 --> 09:54.480 + flexible, expressive, and also well defined than traditional + +09:54.480 --> 09:56.440 + math notation, which is none of those things. + +09:56.440 --> 09:59.160 + Math notation is awful. + +09:59.160 --> 10:02.840 + And so he actually turned that into a programming language. + +10:02.840 --> 10:06.720 + Because this was the late 50s, all the names were available. + +10:06.720 --> 10:10.520 + So he called his programming language, or APL. + +10:10.520 --> 10:11.160 + APL, what? + +10:11.160 --> 10:15.360 + So APL is a implementation of notation + +10:15.360 --> 10:18.280 + as a tool for thought, by which he means math notation. + +10:18.280 --> 10:22.880 + And Ken and his son went on to do many things, + +10:22.880 --> 10:26.720 + but eventually they actually produced a new language that + +10:26.720 --> 10:28.440 + was built on top of all the learnings of APL. + +10:28.440 --> 10:32.800 + And that was called J. And J is the most + +10:32.800 --> 10:41.040 + expressive, composable, beautifully designed language + +10:41.040 --> 10:42.400 + I've ever seen. + +10:42.400 --> 10:44.520 + Does it have object oriented components? + +10:44.520 --> 10:45.520 + Does it have that kind of thing? + +10:45.520 --> 10:46.240 + Not really. + +10:46.240 --> 10:47.720 + It's an array oriented language. + +10:47.720 --> 10:51.400 + It's the third path. + +10:51.400 --> 10:52.760 + Are you saying array? + +10:52.760 --> 10:53.720 + Array oriented. + +10:53.720 --> 10:54.200 + Yeah. + +10:54.200 --> 10:55.480 + It needs to be array oriented. + +10:55.480 --> 10:57.480 + So array oriented means that you generally + +10:57.480 --> 10:59.520 + don't use any loops. + +10:59.520 --> 11:02.240 + But the whole thing is done with kind + +11:02.240 --> 11:06.360 + of an extreme version of broadcasting, + +11:06.360 --> 11:09.880 + if you're familiar with that NumPy slash Python concept. + +11:09.880 --> 11:14.240 + So you do a lot with one line of code. + +11:14.240 --> 11:17.520 + It looks a lot like math. + +11:17.520 --> 11:20.280 + Notation is basically highly compact. + +11:20.280 --> 11:22.800 + And the idea is that you can kind of, + +11:22.800 --> 11:24.760 + because you can do so much with one line of code, + +11:24.760 --> 11:27.720 + a single screen of code is very unlikely to, + +11:27.720 --> 11:31.080 + you very rarely need more than that to express your program. + +11:31.080 --> 11:33.240 + And so you can kind of keep it all in your head. + +11:33.240 --> 11:36.000 + And you can kind of clearly communicate it. + +11:36.000 --> 11:41.560 + It's interesting that APL created two main branches, K and J. + +11:41.560 --> 11:47.920 + J is this kind of like open source niche community of crazy + +11:47.920 --> 11:49.360 + enthusiasts like me. + +11:49.360 --> 11:52.120 + And then the other path, K, was fascinating. + +11:52.120 --> 11:56.600 + It's an astonishingly expensive programming language, + +11:56.600 --> 12:01.920 + which many of the world's most ludicrously rich hedge funds + +12:01.920 --> 12:02.840 + use. + +12:02.840 --> 12:06.640 + So the entire K machine is so small, + +12:06.640 --> 12:09.320 + it sits inside level three cache on your CPU. + +12:09.320 --> 12:14.040 + And it easily wins every benchmark I've ever seen + +12:14.040 --> 12:16.440 + in terms of data processing speed. + +12:16.440 --> 12:17.840 + But you don't come across it very much, + +12:17.840 --> 12:22.640 + because it's like $100,000 per CPU to run it. + +12:22.640 --> 12:26.240 + But it's like this path of programming languages + +12:26.240 --> 12:29.760 + is just so much, I don't know, so much more powerful + +12:29.760 --> 12:33.840 + in every way than the ones that almost anybody uses every day. + +12:33.840 --> 12:37.400 + So it's all about computation. + +12:37.400 --> 12:38.360 + It's really focusing on it. + +12:38.360 --> 12:40.640 + Pretty heavily focused on computation. + +12:40.640 --> 12:44.320 + I mean, so much of programming is data processing + +12:44.320 --> 12:45.640 + by definition. + +12:45.640 --> 12:49.000 + And so there's a lot of things you can do with it. + +12:49.000 --> 12:51.320 + But yeah, there's not much work being + +12:51.320 --> 12:57.080 + done on making user interface toolkills or whatever. + +12:57.080 --> 12:59.400 + I mean, there's some, but they're not great. + +12:59.400 --> 13:03.160 + At the same time, you've done a lot of stuff with Perl and Python. + +13:03.160 --> 13:08.320 + So what does that fit into the picture of J and K and APL + +13:08.320 --> 13:08.880 + and Python? + +13:08.880 --> 13:12.400 + Well, it's just much more pragmatic. + +13:12.400 --> 13:13.960 + In the end, you kind of have to end up + +13:13.960 --> 13:17.960 + where the libraries are. + +13:17.960 --> 13:21.320 + Because to me, my focus is on productivity. + +13:21.320 --> 13:23.800 + I just want to get stuff done and solve problems. + +13:23.800 --> 13:27.360 + So Perl was great. + +13:27.360 --> 13:29.760 + I created an email company called Fastmail. + +13:29.760 --> 13:35.200 + And Perl was great, because back in the late 90s, early 2000s, + +13:35.200 --> 13:38.160 + it just had a lot of stuff it could do. + +13:38.160 --> 13:41.840 + I still had to write my own monitoring system + +13:41.840 --> 13:43.840 + and my own web framework and my own whatever, + +13:43.840 --> 13:45.760 + because none of that stuff existed. + +13:45.760 --> 13:50.280 + But it was a super flexible language to do that in. + +13:50.280 --> 13:52.720 + And you used Perl for Fastmail. + +13:52.720 --> 13:54.520 + You used it as a back end. + +13:54.520 --> 13:55.800 + So everything was written in Perl? + +13:55.800 --> 13:56.520 + Yeah. + +13:56.520 --> 13:58.720 + Yeah, everything was Perl. + +13:58.720 --> 14:04.480 + Why do you think Perl hasn't succeeded or hasn't dominated + +14:04.480 --> 14:07.120 + the market where Python really takes over a lot of the + +14:07.120 --> 14:08.200 + tests? + +14:08.200 --> 14:09.640 + Well, I mean, Perl did dominate. + +14:09.640 --> 14:13.080 + It was everything, everywhere. + +14:13.080 --> 14:19.920 + But then the guy that ran Perl, Larry Wall, + +14:19.920 --> 14:22.280 + just didn't put the time in anymore. + +14:22.280 --> 14:29.680 + And no project can be successful if there isn't. + +14:29.680 --> 14:32.640 + Particularly one that started with a strong leader that + +14:32.640 --> 14:35.040 + loses that strong leadership. + +14:35.040 --> 14:38.040 + So then Python has kind of replaced it. + +14:38.040 --> 14:45.040 + Python is a lot less elegant language in nearly every way. + +14:45.040 --> 14:48.880 + But it has the data science libraries. + +14:48.880 --> 14:51.240 + And a lot of them are pretty great. + +14:51.240 --> 14:58.280 + So I kind of use it because it's the best we have. + +14:58.280 --> 15:01.800 + But it's definitely not good enough. + +15:01.800 --> 15:04.040 + What do you think the future of programming looks like? + +15:04.040 --> 15:06.880 + What do you hope the future of programming looks like if we + +15:06.880 --> 15:10.200 + zoom in on the computational fields on data science + +15:10.200 --> 15:11.800 + and machine learning? + +15:11.800 --> 15:19.440 + I hope Swift is successful because the goal of Swift, + +15:19.440 --> 15:21.000 + the way Chris Latna describes it, + +15:21.000 --> 15:22.640 + is to be infinitely hackable. + +15:22.640 --> 15:23.480 + And that's what I want. + +15:23.480 --> 15:26.920 + I want something where me and the people I do research with + +15:26.920 --> 15:30.360 + and my students can look at and change everything + +15:30.360 --> 15:32.000 + from top to bottom. + +15:32.000 --> 15:36.240 + There's nothing mysterious and magical and inaccessible. + +15:36.240 --> 15:38.600 + Unfortunately, with Python, it's the opposite of that + +15:38.600 --> 15:42.640 + because Python is so slow, it's extremely unhackable. + +15:42.640 --> 15:44.840 + You get to a point where it's like, OK, from here on down + +15:44.840 --> 15:47.320 + at C. So your debugger doesn't work in the same way. + +15:47.320 --> 15:48.920 + Your profiler doesn't work in the same way. + +15:48.920 --> 15:50.880 + Your build system doesn't work in the same way. + +15:50.880 --> 15:53.760 + It's really not very hackable at all. + +15:53.760 --> 15:55.600 + What's the part you like to be hackable? + +15:55.600 --> 16:00.120 + Is it for the objective of optimizing training + +16:00.120 --> 16:02.600 + of neural networks, inference of neural networks? + +16:02.600 --> 16:04.360 + Is it performance of the system? + +16:04.360 --> 16:08.440 + Or is there some nonperformance related, just creative idea? + +16:08.440 --> 16:09.080 + It's everything. + +16:09.080 --> 16:15.480 + I mean, in the end, I want to be productive as a practitioner. + +16:15.480 --> 16:18.440 + So at the moment, our understanding of deep learning + +16:18.440 --> 16:20.080 + is incredibly primitive. + +16:20.080 --> 16:21.520 + There's very little we understand. + +16:21.520 --> 16:24.200 + Most things don't work very well, even though it works better + +16:24.200 --> 16:26.200 + than anything else out there. + +16:26.200 --> 16:28.760 + There's so many opportunities to make it better. + +16:28.760 --> 16:34.360 + So you look at any domain area like speech recognition + +16:34.360 --> 16:37.720 + with deep learning or natural language processing + +16:37.720 --> 16:39.440 + classification with deep learning or whatever. + +16:39.440 --> 16:41.960 + Every time I look at an area with deep learning, + +16:41.960 --> 16:44.480 + I always see like, oh, it's terrible. + +16:44.480 --> 16:47.560 + There's lots and lots of obviously stupid ways + +16:47.560 --> 16:50.000 + to do things that need to be fixed. + +16:50.000 --> 16:53.320 + So then I want to be able to jump in there and quickly + +16:53.320 --> 16:54.880 + experiment and make them better. + +16:54.880 --> 16:59.320 + Do you think the programming language has a role in that? + +16:59.320 --> 17:00.280 + Huge role, yeah. + +17:00.280 --> 17:07.080 + So currently, Python has a big gap in terms of our ability + +17:07.080 --> 17:11.880 + to innovate particularly around recurrent neural networks + +17:11.880 --> 17:16.840 + and natural language processing because it's so slow. + +17:16.840 --> 17:20.200 + The actual loop where we actually loop through words, + +17:20.200 --> 17:23.760 + we have to do that whole thing in CUDA C. + +17:23.760 --> 17:27.600 + So we actually can't innovate with the kernel, the heart, + +17:27.600 --> 17:31.560 + of that most important algorithm. + +17:31.560 --> 17:33.680 + And it's just a huge problem. + +17:33.680 --> 17:36.600 + And this happens all over the place. + +17:36.600 --> 17:40.080 + So we hit research limitations. + +17:40.080 --> 17:42.840 + Another example, convolutional neural networks, which + +17:42.840 --> 17:46.800 + are actually the most popular architecture for lots of things, + +17:46.800 --> 17:48.920 + maybe most things in deep learning. + +17:48.920 --> 17:50.360 + We almost certainly should be using + +17:50.360 --> 17:54.600 + sparse convolutional neural networks, but only like two + +17:54.600 --> 17:56.800 + people are because to do it, you have + +17:56.800 --> 17:59.920 + to rewrite all of that CUDA C level stuff. + +17:59.920 --> 18:04.520 + And yeah, just research, just in practitioners, don't. + +18:04.520 --> 18:09.240 + So there's just big gaps in what people actually research on, + +18:09.240 --> 18:11.640 + what people actually implement because of the programming + +18:11.640 --> 18:13.240 + language problem. + +18:13.240 --> 18:17.560 + So you think it's just too difficult + +18:17.560 --> 18:23.480 + to write in CUDA C that a higher level programming language + +18:23.480 --> 18:30.520 + like Swift should enable the easier, + +18:30.520 --> 18:33.160 + fooling around, create stuff with RNNs, + +18:33.160 --> 18:34.920 + or sparse convolutional neural networks? + +18:34.920 --> 18:35.920 + Kind of. + +18:35.920 --> 18:38.520 + Who is at fault? + +18:38.520 --> 18:42.320 + Who is at charge of making it easy for a researcher to play around? + +18:42.320 --> 18:43.520 + I mean, no one's at fault. + +18:43.520 --> 18:45.120 + Just nobody's got a round to it yet. + +18:45.120 --> 18:47.080 + Or it's just it's hard. + +18:47.080 --> 18:51.800 + And I mean, part of the fault is that we ignored that whole APL + +18:51.800 --> 18:55.640 + kind of direction, or nearly everybody did for 60 years, + +18:55.640 --> 18:57.720 + 50 years. + +18:57.720 --> 18:59.920 + But recently, people have been starting + +18:59.920 --> 19:04.840 + to reinvent pieces of that and kind of create some interesting + +19:04.840 --> 19:07.400 + new directions in the compiler technology. + +19:07.400 --> 19:11.760 + So the place where that's particularly happening right now + +19:11.760 --> 19:14.920 + is something called MLIR, which is something that, again, + +19:14.920 --> 19:18.000 + Chris Lattener, the Swift guy, is leading. + +19:18.000 --> 19:20.080 + And because it's actually not going + +19:20.080 --> 19:22.160 + to be Swift on its own that solves this problem. + +19:22.160 --> 19:24.880 + Because the problem is that currently writing + +19:24.880 --> 19:32.360 + a acceptably fast GPU program is too complicated, + +19:32.360 --> 19:33.680 + regardless of what language you use. + +19:36.480 --> 19:38.680 + And that's just because if you have to deal with the fact + +19:38.680 --> 19:43.160 + that I've got 10,000 threads and I have to synchronize between them + +19:43.160 --> 19:45.360 + all, and I have to put my thing into grid blocks + +19:45.360 --> 19:47.040 + and think about warps and all this stuff, + +19:47.040 --> 19:50.720 + it's just so much boilerplate that to do that well, + +19:50.720 --> 19:52.240 + you have to be a specialist at that. + +19:52.240 --> 19:58.200 + And it's going to be a year's work to optimize that algorithm + +19:58.200 --> 19:59.720 + in that way. + +19:59.720 --> 20:04.640 + But with things like TensorFlow Comprehensions, and Tile, + +20:04.640 --> 20:08.880 + and MLIR, and TVM, there's all these various projects which + +20:08.880 --> 20:11.840 + are all about saying, let's let people + +20:11.840 --> 20:16.080 + create domain specific languages for tensor + +20:16.080 --> 20:16.880 + computations. + +20:16.880 --> 20:19.120 + These are the kinds of things we do generally + +20:19.120 --> 20:21.640 + on the GPU for deep learning, and then + +20:21.640 --> 20:28.280 + have a compiler which can optimize that tensor computation. + +20:28.280 --> 20:31.440 + A lot of this work is actually sitting on top of a project + +20:31.440 --> 20:36.040 + called Halide, which is a mind blowing project + +20:36.040 --> 20:38.880 + where they came up with such a domain specific language. + +20:38.880 --> 20:41.240 + In fact, two, one domain specific language for expressing, + +20:41.240 --> 20:43.840 + this is what my tensor computation is. + +20:43.840 --> 20:46.320 + And another domain specific language for expressing, + +20:46.320 --> 20:50.320 + this is the way I want you to structure + +20:50.320 --> 20:53.040 + the compilation of that, and do it block by block + +20:53.040 --> 20:54.960 + and do these bits in parallel. + +20:54.960 --> 20:57.760 + And they were able to show how you can compress + +20:57.760 --> 21:02.880 + the amount of code by 10x compared to optimized GPU + +21:02.880 --> 21:05.600 + code and get the same performance. + +21:05.600 --> 21:08.480 + So these are the things that are sitting on top + +21:08.480 --> 21:12.240 + of that kind of research, and MLIR + +21:12.240 --> 21:15.160 + is pulling a lot of those best practices together. + +21:15.160 --> 21:17.160 + And now we're starting to see work done + +21:17.160 --> 21:21.400 + on making all of that directly accessible through Swift + +21:21.400 --> 21:25.040 + so that I could use Swift to write those domain specific + +21:25.040 --> 21:25.880 + languages. + +21:25.880 --> 21:29.520 + And hopefully we'll get then Swift CUDA kernels + +21:29.520 --> 21:31.720 + written in a very expressive and concise way that + +21:31.720 --> 21:36.280 + looks a bit like J in APL, and then Swift layers on top + +21:36.280 --> 21:38.360 + of that, and then a Swift UI on top of that, + +21:38.360 --> 21:42.600 + and it'll be so nice if we can get to that point. + +21:42.600 --> 21:48.560 + Now does it all eventually boil down to CUDA and NVIDIA GPUs? + +21:48.560 --> 21:50.120 + Unfortunately at the moment it does, + +21:50.120 --> 21:52.600 + but one of the nice things about MLIR, + +21:52.600 --> 21:56.120 + if AMD ever gets their act together, which they probably + +21:56.120 --> 21:59.040 + want, is that they or others could + +21:59.040 --> 22:05.000 + write MLIR backends for other GPUs + +22:05.000 --> 22:10.320 + or rather tensor computation devices, of which today + +22:10.320 --> 22:15.520 + there are increasing number like Graphcore or Vertex AI + +22:15.520 --> 22:18.840 + or whatever. + +22:18.840 --> 22:22.600 + So yeah, being able to target lots of backends + +22:22.600 --> 22:23.960 + would be another benefit of this, + +22:23.960 --> 22:26.680 + and the market really needs competition, + +22:26.680 --> 22:28.680 + because at the moment NVIDIA is massively + +22:28.680 --> 22:33.640 + overcharging for their kind of enterprise class cards, + +22:33.640 --> 22:36.720 + because there is no serious competition, + +22:36.720 --> 22:39.280 + because nobody else is doing the software properly. + +22:39.280 --> 22:41.400 + In the cloud there is some competition, right? + +22:41.400 --> 22:45.080 + But not really, other than TPUs perhaps, + +22:45.080 --> 22:49.040 + but TPUs are almost unprogrammable at the moment. + +22:49.040 --> 22:51.080 + TPUs have the same problem that you can't. + +22:51.080 --> 22:51.760 + It's even worse. + +22:51.760 --> 22:54.800 + So TPUs, Google actually made an explicit decision + +22:54.800 --> 22:57.200 + to make them almost entirely unprogrammable, + +22:57.200 --> 22:59.960 + because they felt that there was too much IP in there, + +22:59.960 --> 23:02.640 + and if they gave people direct access to program them, + +23:02.640 --> 23:04.360 + people would learn their secrets. + +23:04.360 --> 23:09.720 + So you can't actually directly program + +23:09.720 --> 23:12.120 + the memory in a TPU. + +23:12.120 --> 23:16.360 + You can't even directly create code that runs on + +23:16.360 --> 23:19.080 + and that you look at on the machine that has the TPU. + +23:19.080 --> 23:20.920 + It all goes through a virtual machine. + +23:20.920 --> 23:23.680 + So all you can really do is this kind of cookie cutter + +23:23.680 --> 23:27.760 + thing of like plug in high level stuff together, + +23:27.760 --> 23:31.440 + which is just super tedious and annoying + +23:31.440 --> 23:33.920 + and totally unnecessary. + +23:33.920 --> 23:40.960 + So tell me if you could, the origin story of fast AI. + +23:40.960 --> 23:45.760 + What is the motivation, its mission, its dream? + +23:45.760 --> 23:50.040 + So I guess the founding story is heavily + +23:50.040 --> 23:51.840 + tied to my previous startup, which + +23:51.840 --> 23:53.960 + is a company called Inletic, which + +23:53.960 --> 23:58.280 + was the first company to focus on deep learning for medicine. + +23:58.280 --> 24:03.240 + And I created that because I saw there was a huge opportunity + +24:03.240 --> 24:07.960 + to, there's about a 10x shortage of the number of doctors + +24:07.960 --> 24:12.120 + in the world and the developing world that we need. + +24:12.120 --> 24:13.840 + I expected it would take about 300 years + +24:13.840 --> 24:16.120 + to train enough doctors to meet that gap. + +24:16.120 --> 24:20.760 + But I guessed that maybe if we used + +24:20.760 --> 24:23.760 + deep learning for some of the analytics, + +24:23.760 --> 24:25.760 + we could maybe make it so you don't need + +24:25.760 --> 24:27.320 + as highly trained doctors. + +24:27.320 --> 24:28.320 + For diagnosis? + +24:28.320 --> 24:29.840 + For diagnosis and treatment planning. + +24:29.840 --> 24:33.440 + Where's the biggest benefit just before get the fast AI? + +24:33.440 --> 24:37.280 + Where's the biggest benefit of AI and medicine that you see + +24:37.280 --> 24:39.440 + today and in the future? + +24:39.440 --> 24:41.960 + Not much happening today in terms of stuff that's actually + +24:41.960 --> 24:42.440 + out there. + +24:42.440 --> 24:43.160 + It's very early. + +24:43.160 --> 24:45.320 + But in terms of the opportunity, it's + +24:45.320 --> 24:51.080 + to take markets like India and China and Indonesia, which + +24:51.080 --> 24:58.120 + have big populations, Africa, small numbers of doctors, + +24:58.120 --> 25:02.440 + and provide diagnostic, particularly treatment + +25:02.440 --> 25:05.160 + planning and triage kind of on device + +25:05.160 --> 25:10.360 + so that if you do a test for malaria or tuberculosis + +25:10.360 --> 25:12.800 + or whatever, you immediately get something + +25:12.800 --> 25:14.840 + that even a health care worker that's + +25:14.840 --> 25:20.360 + had a month of training can get a very high quality + +25:20.360 --> 25:23.480 + assessment of whether the patient might be at risk + +25:23.480 --> 25:27.480 + until OK, we'll send them off to a hospital. + +25:27.480 --> 25:31.720 + So for example, in Africa, outside of South Africa, + +25:31.720 --> 25:34.080 + there's only five pediatric radiologists + +25:34.080 --> 25:35.320 + for the entire continent. + +25:35.320 --> 25:37.200 + So most countries don't have any. + +25:37.200 --> 25:39.240 + So if your kid is sick and they need something + +25:39.240 --> 25:41.200 + diagnosed through medical imaging, + +25:41.200 --> 25:44.040 + the person, even if you're able to get medical imaging done, + +25:44.040 --> 25:48.920 + the person that looks at it will be a nurse at best. + +25:48.920 --> 25:52.480 + But actually, in India, for example, and China, + +25:52.480 --> 25:54.760 + almost no x rays are read by anybody, + +25:54.760 --> 25:59.400 + by any trained professional, because they don't have enough. + +25:59.400 --> 26:02.880 + So if instead we had an algorithm that + +26:02.880 --> 26:10.080 + could take the most likely high risk 5% and say triage, + +26:10.080 --> 26:13.280 + basically say, OK, somebody needs to look at this, + +26:13.280 --> 26:16.240 + it would massively change the kind of way + +26:16.240 --> 26:20.640 + that what's possible with medicine in the developing world. + +26:20.640 --> 26:23.680 + And remember, increasingly, they have money. + +26:23.680 --> 26:24.800 + They're the developing world. + +26:24.800 --> 26:26.160 + They're not the poor world, the developing world. + +26:26.160 --> 26:26.920 + So they have the money. + +26:26.920 --> 26:28.480 + So they're building the hospitals. + +26:28.480 --> 26:31.960 + They're getting the diagnostic equipment. + +26:31.960 --> 26:34.880 + But there's no way for a very long time + +26:34.880 --> 26:38.480 + will they be able to have the expertise. + +26:38.480 --> 26:39.760 + Shortage of expertise. + +26:39.760 --> 26:42.720 + OK, and that's where the deep learning systems + +26:42.720 --> 26:46.040 + can step in and magnify the expertise they do have. + +26:46.040 --> 26:47.840 + Exactly. + +26:47.840 --> 26:54.160 + So you do see, just to linger a little bit longer, + +26:54.160 --> 26:58.520 + the interaction, do you still see the human experts still + +26:58.520 --> 26:59.840 + at the core of the system? + +26:59.840 --> 27:00.480 + Yeah, absolutely. + +27:00.480 --> 27:01.720 + Is there something in medicine that + +27:01.720 --> 27:03.760 + could be automated almost completely? + +27:03.760 --> 27:06.360 + I don't see the point of even thinking about that, + +27:06.360 --> 27:08.480 + because we have such a shortage of people. + +27:08.480 --> 27:12.160 + Why would we want to find a way not to use them? + +27:12.160 --> 27:13.840 + Like, we have people. + +27:13.840 --> 27:17.200 + So the idea of, even from an economic point of view, + +27:17.200 --> 27:19.800 + if you can make them 10x more productive, + +27:19.800 --> 27:21.600 + getting rid of the person doesn't + +27:21.600 --> 27:23.880 + impact your unit economics at all. + +27:23.880 --> 27:26.680 + And it totally involves the fact that there are things + +27:26.680 --> 27:28.760 + people do better than machines. + +27:28.760 --> 27:33.120 + So it's just, to me, that's not a useful way + +27:33.120 --> 27:34.120 + of framing the problem. + +27:34.120 --> 27:36.440 + I guess, just to clarify, I guess I + +27:36.440 --> 27:40.560 + meant there may be some problems where you can avoid even + +27:40.560 --> 27:42.160 + going to the expert ever. + +27:42.160 --> 27:46.160 + Sort of maybe preventative care or some basic stuff, + +27:46.160 --> 27:47.800 + the low hanging fruit, allowing the expert + +27:47.800 --> 27:51.320 + to focus on the things that are really that. + +27:51.320 --> 27:52.960 + Well, that's what the triage would do, right? + +27:52.960 --> 28:00.760 + So the triage would say, OK, 99% sure there's nothing here. + +28:00.760 --> 28:04.040 + So that can be done on device. + +28:04.040 --> 28:05.920 + And they can just say, OK, go home. + +28:05.920 --> 28:10.520 + So the experts are being used to look at the stuff which + +28:10.520 --> 28:12.240 + has some chance it's worth looking at, + +28:12.240 --> 28:15.720 + which most things is not. + +28:15.720 --> 28:16.280 + It's fine. + +28:16.280 --> 28:19.840 + Why do you think we haven't quite made progress on that yet + +28:19.840 --> 28:27.480 + in terms of the scale of how much AI is applied in the method? + +28:27.480 --> 28:28.400 + There's a lot of reasons. + +28:28.400 --> 28:29.640 + I mean, one is it's pretty new. + +28:29.640 --> 28:32.040 + I only started in late 2014. + +28:32.040 --> 28:35.920 + And before that, it's hard to express + +28:35.920 --> 28:37.760 + to what degree the medical world was not + +28:37.760 --> 28:40.720 + aware of the opportunities here. + +28:40.720 --> 28:45.520 + So I went to RSNA, which is the world's largest radiology + +28:45.520 --> 28:46.240 + conference. + +28:46.240 --> 28:50.040 + And I told everybody I could, like, + +28:50.040 --> 28:51.800 + I'm doing this thing with deep learning. + +28:51.800 --> 28:53.320 + Please come and check it out. + +28:53.320 --> 28:56.880 + And no one had any idea what I was talking about. + +28:56.880 --> 28:59.640 + No one had any interest in it. + +28:59.640 --> 29:05.040 + So we've come from absolute zero, which is hard. + +29:05.040 --> 29:09.920 + And then the whole regulatory framework, education system, + +29:09.920 --> 29:13.400 + everything is just set up to think of doctoring + +29:13.400 --> 29:14.920 + in a very different way. + +29:14.920 --> 29:16.400 + So today, there is a small number + +29:16.400 --> 29:22.040 + of people who are deep learning practitioners and doctors + +29:22.040 --> 29:22.960 + at the same time. + +29:22.960 --> 29:25.040 + And we're starting to see the first ones come out + +29:25.040 --> 29:26.520 + of their PhD programs. + +29:26.520 --> 29:33.960 + So Zach Cahane over in Boston, Cambridge + +29:33.960 --> 29:41.040 + has a number of students now who are data science experts, + +29:41.040 --> 29:46.400 + deep learning experts, and actual medical doctors. + +29:46.400 --> 29:49.480 + Quite a few doctors have completed our fast AI course + +29:49.480 --> 29:54.920 + now and are publishing papers and creating journal reading + +29:54.920 --> 29:58.040 + groups in the American Council of Radiology. + +29:58.040 --> 30:00.280 + And it's just starting to happen. + +30:00.280 --> 30:02.840 + But it's going to be a long process. + +30:02.840 --> 30:04.920 + The regulators have to learn how to regulate this. + +30:04.920 --> 30:08.720 + They have to build guidelines. + +30:08.720 --> 30:12.120 + And then the lawyers at hospitals + +30:12.120 --> 30:15.080 + have to develop a new way of understanding + +30:15.080 --> 30:18.680 + that sometimes it makes sense for data + +30:18.680 --> 30:24.880 + to be looked at in raw form in large quantities + +30:24.880 --> 30:27.000 + in order to create world changing results. + +30:27.000 --> 30:30.080 + Yeah, there's a regulation around data, all that. + +30:30.080 --> 30:33.840 + It sounds probably the hardest problem, + +30:33.840 --> 30:36.760 + but it sounds reminiscent of autonomous vehicles as well. + +30:36.760 --> 30:38.760 + Many of the same regulatory challenges, + +30:38.760 --> 30:40.560 + many of the same data challenges. + +30:40.560 --> 30:42.160 + Yeah, I mean, funnily enough, the problem + +30:42.160 --> 30:44.880 + is less the regulation and more the interpretation + +30:44.880 --> 30:48.200 + of that regulation by lawyers in hospitals. + +30:48.200 --> 30:52.560 + So HIPAA was actually designed. + +30:52.560 --> 30:56.400 + The P in HIPAA does not stand for privacy. + +30:56.400 --> 30:57.640 + It stands for portability. + +30:57.640 --> 31:01.200 + It's actually meant to be a way that data can be used. + +31:01.200 --> 31:04.400 + And it was created with lots of gray areas + +31:04.400 --> 31:06.560 + because the idea is that would be more practical + +31:06.560 --> 31:10.480 + and it would help people to use this legislation + +31:10.480 --> 31:13.680 + to actually share data in a more thoughtful way. + +31:13.680 --> 31:15.320 + Unfortunately, it's done the opposite + +31:15.320 --> 31:18.880 + because when a lawyer sees a gray area, they see, oh, + +31:18.880 --> 31:22.440 + if we don't know we won't get sued, then we can't do it. + +31:22.440 --> 31:26.360 + So HIPAA is not exactly the problem. + +31:26.360 --> 31:30.080 + The problem is more that hospital lawyers + +31:30.080 --> 31:34.720 + are not incented to make bold decisions + +31:34.720 --> 31:36.520 + about data portability. + +31:36.520 --> 31:40.480 + Or even to embrace technology that saves lives. + +31:40.480 --> 31:42.440 + They more want to not get in trouble + +31:42.440 --> 31:44.280 + for embracing that technology. + +31:44.280 --> 31:47.840 + Also, it is also saves lives in a very abstract way, + +31:47.840 --> 31:49.840 + which is like, oh, we've been able to release + +31:49.840 --> 31:52.360 + these 100,000 anonymous records. + +31:52.360 --> 31:55.360 + I can't point at the specific person whose life that's saved. + +31:55.360 --> 31:57.760 + I can say like, oh, we've ended up with this paper + +31:57.760 --> 32:02.200 + which found this result, which diagnosed 1,000 more people + +32:02.200 --> 32:04.200 + than we would have otherwise, but it's like, + +32:04.200 --> 32:07.360 + which ones were helped, it's very abstract. + +32:07.360 --> 32:09.400 + Yeah, and on the counter side of that, + +32:09.400 --> 32:13.080 + you may be able to point to a life that was taken + +32:13.080 --> 32:14.360 + because of something that was... + +32:14.360 --> 32:18.240 + Yeah, or a person whose privacy was violated. + +32:18.240 --> 32:20.360 + It's like, oh, this specific person, + +32:20.360 --> 32:25.480 + you know, there was deidentified. + +32:25.480 --> 32:27.360 + Just a fascinating topic. + +32:27.360 --> 32:28.360 + We're jumping around. + +32:28.360 --> 32:32.880 + We'll get back to fast AI, but on the question of privacy, + +32:32.880 --> 32:38.160 + data is the fuel for so much innovation in deep learning. + +32:38.160 --> 32:39.840 + What's your sense on privacy, + +32:39.840 --> 32:44.080 + whether we're talking about Twitter, Facebook, YouTube, + +32:44.080 --> 32:48.720 + just the technologies like in the medical field + +32:48.720 --> 32:53.440 + that rely on people's data in order to create impact? + +32:53.440 --> 32:58.840 + How do we get that right, respecting people's privacy + +32:58.840 --> 33:03.360 + and yet creating technology that is learned from data? + +33:03.360 --> 33:11.480 + One of my areas of focus is on doing more with less data, + +33:11.480 --> 33:15.000 + which so most vendors, unfortunately, are strongly + +33:15.000 --> 33:20.000 + centred to find ways to require more data and more computation. + +33:20.000 --> 33:24.000 + So Google and IBM being the most obvious... + +33:24.000 --> 33:26.000 + IBM. + +33:26.000 --> 33:30.600 + Yeah, so Watson, you know, so Google and IBM both strongly push + +33:30.600 --> 33:35.400 + the idea that they have more data and more computation + +33:35.400 --> 33:37.800 + and more intelligent people than anybody else, + +33:37.800 --> 33:39.840 + and so you have to trust them to do things + +33:39.840 --> 33:42.600 + because nobody else can do it. + +33:42.600 --> 33:45.360 + And Google's very upfront about this, + +33:45.360 --> 33:48.680 + like Jeff Dain has gone out there and given talks and said, + +33:48.680 --> 33:52.840 + our goal is to require 1,000 times more computation, + +33:52.840 --> 33:55.120 + but less people. + +33:55.120 --> 34:00.600 + Our goal is to use the people that you have better + +34:00.600 --> 34:02.960 + and the data you have better and the computation you have better. + +34:02.960 --> 34:06.000 + So one of the things that we've discovered is, + +34:06.000 --> 34:11.080 + or at least highlighted, is that you very, very, very often + +34:11.080 --> 34:13.360 + don't need much data at all. + +34:13.360 --> 34:16.160 + And so the data you already have in your organization + +34:16.160 --> 34:19.240 + will be enough to get state of the art results. + +34:19.240 --> 34:22.600 + So like my starting point would be to kind of say around privacy + +34:22.600 --> 34:25.760 + is a lot of people are looking for ways + +34:25.760 --> 34:28.120 + to share data and aggregate data, + +34:28.120 --> 34:29.920 + but I think often that's unnecessary. + +34:29.920 --> 34:32.160 + They assume that they need more data than they do + +34:32.160 --> 34:35.240 + because they're not familiar with the basics of transfer + +34:35.240 --> 34:38.440 + learning, which is this critical technique + +34:38.440 --> 34:42.000 + for needing orders of magnitude less data. + +34:42.000 --> 34:44.680 + Is your sense, one reason you might want to collect data + +34:44.680 --> 34:50.440 + from everyone is like in the recommender system context, + +34:50.440 --> 34:54.520 + where your individual, Jeremy Howard's individual data + +34:54.520 --> 34:58.600 + is the most useful for providing a product that's + +34:58.600 --> 34:59.880 + impactful for you. + +34:59.880 --> 35:02.240 + So for giving you advertisements, + +35:02.240 --> 35:07.640 + for recommending to you movies, for doing medical diagnosis. + +35:07.640 --> 35:11.720 + Is your sense we can build with a small amount of data, + +35:11.720 --> 35:16.040 + general models that will have a huge impact for most people, + +35:16.040 --> 35:19.120 + that we don't need to have data from each individual? + +35:19.120 --> 35:20.560 + On the whole, I'd say yes. + +35:20.560 --> 35:26.400 + I mean, there are things like, recommender systems + +35:26.400 --> 35:30.960 + have this cold start problem, where Jeremy is a new customer. + +35:30.960 --> 35:33.280 + We haven't seen him before, so we can't recommend him things + +35:33.280 --> 35:36.520 + based on what else he's bought and liked with us. + +35:36.520 --> 35:39.440 + And there's various workarounds to that. + +35:39.440 --> 35:41.160 + A lot of music programs will start out + +35:41.160 --> 35:44.920 + by saying, which of these artists do you like? + +35:44.920 --> 35:46.800 + Which of these albums do you like? + +35:46.800 --> 35:49.800 + Which of these songs do you like? + +35:49.800 --> 35:51.040 + Netflix used to do that. + +35:51.040 --> 35:55.320 + Nowadays, people don't like that because they think, oh, + +35:55.320 --> 35:57.400 + we don't want to bother the user. + +35:57.400 --> 36:00.560 + So you could work around that by having some kind of data + +36:00.560 --> 36:04.240 + sharing where you get my marketing record from Axiom + +36:04.240 --> 36:06.360 + or whatever and try to question that. + +36:06.360 --> 36:12.360 + To me, the benefit to me and to society + +36:12.360 --> 36:16.520 + of saving me five minutes on answering some questions + +36:16.520 --> 36:23.520 + versus the negative externalities of the privacy issue + +36:23.520 --> 36:24.800 + doesn't add up. + +36:24.800 --> 36:26.600 + So I think a lot of the time, the places + +36:26.600 --> 36:30.520 + where people are invading our privacy in order + +36:30.520 --> 36:35.360 + to provide convenience is really about just trying + +36:35.360 --> 36:36.880 + to make them more money. + +36:36.880 --> 36:40.760 + And they move these negative externalities + +36:40.760 --> 36:44.360 + into places that they don't have to pay for them. + +36:44.360 --> 36:48.120 + So when you actually see regulations + +36:48.120 --> 36:50.560 + appear that actually cause the companies that + +36:50.560 --> 36:52.360 + create these negative externalities to have + +36:52.360 --> 36:54.320 + to pay for it themselves, they say, well, + +36:54.320 --> 36:56.160 + we can't do it anymore. + +36:56.160 --> 36:58.240 + So the cost is actually too high. + +36:58.240 --> 37:02.280 + But for something like medicine, the hospital + +37:02.280 --> 37:06.440 + has my medical imaging, my pathology studies, + +37:06.440 --> 37:08.920 + my medical records. + +37:08.920 --> 37:11.920 + And also, I own my medical data. + +37:11.920 --> 37:16.960 + So I help a startup called DocAI. + +37:16.960 --> 37:19.760 + One of the things DocAI does is that it has an app. + +37:19.760 --> 37:26.120 + You can connect to Sutter Health and Labcore and Walgreens + +37:26.120 --> 37:29.840 + and download your medical data to your phone + +37:29.840 --> 37:33.560 + and then upload it, again, at your discretion + +37:33.560 --> 37:36.040 + to share it as you wish. + +37:36.040 --> 37:38.440 + So with that kind of approach, we + +37:38.440 --> 37:41.160 + can share our medical information + +37:41.160 --> 37:44.840 + with the people we want to. + +37:44.840 --> 37:45.720 + Yeah, so control. + +37:45.720 --> 37:48.240 + I mean, really being able to control who you share it with + +37:48.240 --> 37:49.760 + and so on. + +37:49.760 --> 37:53.080 + So that has a beautiful, interesting tangent + +37:53.080 --> 37:59.360 + to return back to the origin story of FastAI. + +37:59.360 --> 38:02.520 + Right, so before I started FastAI, + +38:02.520 --> 38:07.160 + I spent a year researching where are the biggest + +38:07.160 --> 38:10.400 + opportunities for deep learning. + +38:10.400 --> 38:14.080 + Because I knew from my time at Kaggle in particular + +38:14.080 --> 38:17.960 + that deep learning had hit this threshold point where it was + +38:17.960 --> 38:20.520 + rapidly becoming the state of the art approach in every area + +38:20.520 --> 38:21.600 + that looked at it. + +38:21.600 --> 38:25.400 + And I'd been working with neural nets for over 20 years. + +38:25.400 --> 38:27.440 + I knew that from a theoretical point of view, + +38:27.440 --> 38:30.760 + once it hit that point, it would do that in just about every + +38:30.760 --> 38:31.600 + domain. + +38:31.600 --> 38:34.480 + And so I spent a year researching + +38:34.480 --> 38:37.120 + what are the domains it's going to have the biggest low hanging + +38:37.120 --> 38:39.400 + fruit in the shortest time period. + +38:39.400 --> 38:43.880 + I picked medicine, but there were so many I could have picked. + +38:43.880 --> 38:47.640 + And so there was a level of frustration for me of like, OK, + +38:47.640 --> 38:50.840 + I'm really glad we've opened up the medical deep learning + +38:50.840 --> 38:53.880 + world and today it's huge, as you know. + +38:53.880 --> 38:58.280 + But we can't do, you know, I can't do everything. + +38:58.280 --> 39:00.400 + I don't even know like, like in medicine, + +39:00.400 --> 39:02.760 + it took me a really long time to even get a sense of like, + +39:02.760 --> 39:05.080 + what kind of problems do medical practitioners solve? + +39:05.080 --> 39:06.400 + What kind of data do they have? + +39:06.400 --> 39:08.520 + Who has that data? + +39:08.520 --> 39:12.480 + So I kind of felt like I need to approach this differently + +39:12.480 --> 39:16.200 + if I want to maximize the positive impact of deep learning. + +39:16.200 --> 39:19.480 + Rather than me picking an area and trying + +39:19.480 --> 39:21.720 + to become good at it and building something, + +39:21.720 --> 39:24.480 + I should let people who are already domain experts + +39:24.480 --> 39:29.240 + in those areas and who already have the data do it themselves. + +39:29.240 --> 39:35.520 + So that was the reason for vast AI is to basically try + +39:35.520 --> 39:38.840 + and figure out how to get deep learning + +39:38.840 --> 39:41.800 + into the hands of people who could benefit from it + +39:41.800 --> 39:45.400 + and help them to do so in as quick and easy and effective + +39:45.400 --> 39:47.080 + a way as possible. + +39:47.080 --> 39:47.560 + Got it. + +39:47.560 --> 39:50.240 + So sort of empower the domain experts. + +39:50.240 --> 39:51.320 + Yeah. + +39:51.320 --> 39:54.200 + And like partly it's because like, + +39:54.200 --> 39:56.280 + unlike most people in this field, + +39:56.280 --> 39:59.960 + my background is very applied and industrial. + +39:59.960 --> 40:02.480 + Like my first job was at McKinsey & Company. + +40:02.480 --> 40:04.640 + I spent 10 years of management consulting. + +40:04.640 --> 40:10.240 + I spend a lot of time with domain experts. + +40:10.240 --> 40:12.800 + You know, so I kind of respect them and appreciate them. + +40:12.800 --> 40:16.440 + And I know that's where the value generation in society is. + +40:16.440 --> 40:21.560 + And so I also know how most of them can't code. + +40:21.560 --> 40:26.320 + And most of them don't have the time to invest, you know, + +40:26.320 --> 40:29.320 + three years in a graduate degree or whatever. + +40:29.320 --> 40:33.520 + So it's like, how do I upskill those domain experts? + +40:33.520 --> 40:36.080 + I think that would be a super powerful thing, + +40:36.080 --> 40:40.200 + you know, the biggest societal impact I could have. + +40:40.200 --> 40:41.680 + So yeah, that was the thinking. + +40:41.680 --> 40:45.680 + So so much of fast AI students and researchers + +40:45.680 --> 40:50.120 + and the things you teach are programmatically minded, + +40:50.120 --> 40:51.520 + practically minded, + +40:51.520 --> 40:55.840 + figuring out ways how to solve real problems and fast. + +40:55.840 --> 40:57.480 + So from your experience, + +40:57.480 --> 41:02.040 + what's the difference between theory and practice of deep learning? + +41:02.040 --> 41:03.680 + Hmm. + +41:03.680 --> 41:07.520 + Well, most of the research in the deep mining world + +41:07.520 --> 41:09.840 + is a total waste of time. + +41:09.840 --> 41:11.040 + Right. That's what I was getting at. + +41:11.040 --> 41:12.200 + Yeah. + +41:12.200 --> 41:16.240 + It's it's a problem in science in general. + +41:16.240 --> 41:19.600 + Scientists need to be published, + +41:19.600 --> 41:21.480 + which means they need to work on things + +41:21.480 --> 41:24.040 + that their peers are extremely familiar with + +41:24.040 --> 41:26.200 + and can recognize in advance in that area. + +41:26.200 --> 41:30.040 + So that means that they all need to work on the same thing. + +41:30.040 --> 41:33.040 + And so it really ink and the thing they work on + +41:33.040 --> 41:35.640 + is nothing to encourage them to work on things + +41:35.640 --> 41:38.840 + that are practically useful. + +41:38.840 --> 41:41.120 + So you get just a whole lot of research, + +41:41.120 --> 41:43.200 + which is minor advances in stuff + +41:43.200 --> 41:44.600 + that's been very highly studied + +41:44.600 --> 41:49.280 + and has no significant practical impact. + +41:49.280 --> 41:50.840 + Whereas the things that really make a difference + +41:50.840 --> 41:52.760 + like I mentioned transfer learning, + +41:52.760 --> 41:55.560 + like if we can do better at transfer learning, + +41:55.560 --> 41:58.160 + then it's this like world changing thing + +41:58.160 --> 42:02.880 + where suddenly like lots more people can do world class work + +42:02.880 --> 42:06.760 + with less resources and less data and. + +42:06.760 --> 42:08.480 + But almost nobody works on that. + +42:08.480 --> 42:10.760 + Or another example, active learning, + +42:10.760 --> 42:11.880 + which is the study of like, + +42:11.880 --> 42:15.880 + how do we get more out of the human beings in the loop? + +42:15.880 --> 42:17.120 + That's my favorite topic. + +42:17.120 --> 42:18.520 + Yeah. So active learning is great, + +42:18.520 --> 42:21.160 + but it's almost nobody working on it + +42:21.160 --> 42:23.800 + because it's just not a trendy thing right now. + +42:23.800 --> 42:27.040 + You know what somebody started to interrupt? + +42:27.040 --> 42:29.720 + He was saying that nobody is publishing + +42:29.720 --> 42:31.520 + on active learning, right? + +42:31.520 --> 42:33.440 + But there's people inside companies, + +42:33.440 --> 42:36.800 + anybody who actually has to solve a problem, + +42:36.800 --> 42:39.600 + they're going to innovate on active learning. + +42:39.600 --> 42:42.080 + Yeah. Everybody kind of reinvents active learning + +42:42.080 --> 42:43.760 + when they actually have to work in practice + +42:43.760 --> 42:46.360 + because they start labeling things and they think, + +42:46.360 --> 42:49.280 + gosh, this is taking a long time and it's very expensive. + +42:49.280 --> 42:51.200 + And then they start thinking, + +42:51.200 --> 42:52.640 + well, why am I labeling everything? + +42:52.640 --> 42:54.840 + I'm only, the machine's only making mistakes + +42:54.840 --> 42:56.040 + on those two classes. + +42:56.040 --> 42:56.880 + They're the hard ones. + +42:56.880 --> 42:58.840 + Maybe I'll just start labeling those two classes + +42:58.840 --> 43:00.360 + and then you start thinking, + +43:00.360 --> 43:01.560 + well, why did I do that manually? + +43:01.560 --> 43:03.000 + Why can't I just get the system to tell me + +43:03.000 --> 43:04.760 + which things are going to be harder steps? + +43:04.760 --> 43:06.200 + It's an obvious thing to do. + +43:06.200 --> 43:11.400 + But yeah, it's just like transfer learning. + +43:11.400 --> 43:14.120 + It's understudied and the academic world + +43:14.120 --> 43:17.440 + just has no reason to care about practical results. + +43:17.440 --> 43:18.360 + The funny thing is, like, + +43:18.360 --> 43:19.920 + I've only really ever written one paper. + +43:19.920 --> 43:21.520 + I hate writing papers. + +43:21.520 --> 43:22.760 + And I didn't even write it. + +43:22.760 --> 43:25.480 + It was my colleague, Sebastian Ruder, who actually wrote it. + +43:25.480 --> 43:28.040 + I just did the research for it. + +43:28.040 --> 43:31.640 + But it was basically introducing successful transfer learning + +43:31.640 --> 43:34.200 + to NLP for the first time. + +43:34.200 --> 43:37.000 + And the algorithm is called ULMfit. + +43:37.000 --> 43:42.320 + And I actually wrote it for the course, + +43:42.320 --> 43:43.720 + for the first day of course. + +43:43.720 --> 43:45.360 + I wanted to teach people NLP. + +43:45.360 --> 43:47.520 + And I thought I only want to teach people practical stuff. + +43:47.520 --> 43:50.560 + And I think the only practical stuff is transfer learning. + +43:50.560 --> 43:53.360 + And I couldn't find any examples of transfer learning in NLP. + +43:53.360 --> 43:54.560 + So I just did it. + +43:54.560 --> 43:57.320 + And I was shocked to find that as soon as I did it, + +43:57.320 --> 44:01.080 + which, you know, the basic prototype took a couple of days, + +44:01.080 --> 44:02.520 + smashed the state of the art + +44:02.520 --> 44:04.760 + on one of the most important data sets in a field + +44:04.760 --> 44:06.720 + that I knew nothing about. + +44:06.720 --> 44:10.400 + And I just thought, well, this is ridiculous. + +44:10.400 --> 44:13.800 + And so I spoke to Sebastian about it. + +44:13.800 --> 44:17.680 + And he kindly offered to write it up the results. + +44:17.680 --> 44:21.360 + And so it ended up being published in ACL, + +44:21.360 --> 44:25.560 + which is the top computational linguistics conference. + +44:25.560 --> 44:28.880 + So like, people do actually care once you do it. + +44:28.880 --> 44:34.160 + But I guess it's difficult for maybe junior researchers. + +44:34.160 --> 44:37.720 + I don't care whether I get citations or papers or whatever. + +44:37.720 --> 44:39.640 + There's nothing in my life that makes that important, + +44:39.640 --> 44:41.240 + which is why I've never actually + +44:41.240 --> 44:43.040 + bothered to write a paper myself. + +44:43.040 --> 44:44.400 + But for people who do, I guess they + +44:44.400 --> 44:50.960 + have to pick the kind of safe option, which is like, + +44:50.960 --> 44:52.720 + yeah, make a slight improvement on something + +44:52.720 --> 44:55.160 + that everybody's already working on. + +44:55.160 --> 44:59.040 + Yeah, nobody does anything interesting or succeeds + +44:59.040 --> 45:01.240 + in life with the safe option. + +45:01.240 --> 45:02.960 + Well, I mean, the nice thing is nowadays, + +45:02.960 --> 45:05.320 + everybody is now working on NLP transfer learning. + +45:05.320 --> 45:12.240 + Because since that time, we've had GPT and GPT2 and BERT. + +45:12.240 --> 45:15.400 + So yeah, once you show that something's possible, + +45:15.400 --> 45:17.680 + everybody jumps in, I guess. + +45:17.680 --> 45:19.320 + I hope to be a part of it. + +45:19.320 --> 45:21.600 + I hope to see more innovation and active learning + +45:21.600 --> 45:22.160 + in the same way. + +45:22.160 --> 45:24.560 + I think transfer learning and active learning + +45:24.560 --> 45:27.360 + are a fascinating public open work. + +45:27.360 --> 45:30.160 + I actually helped start a startup called Platform AI, which + +45:30.160 --> 45:31.760 + is really all about active learning. + +45:31.760 --> 45:34.200 + And yeah, it's been interesting trying + +45:34.200 --> 45:36.920 + to kind of see what research is out there + +45:36.920 --> 45:37.800 + and make the most of it. + +45:37.800 --> 45:39.200 + And there's basically none. + +45:39.200 --> 45:41.040 + So we've had to do all our own research. + +45:41.040 --> 45:44.240 + Once again, and just as you described, + +45:44.240 --> 45:47.640 + can you tell the story of the Stanford competition, + +45:47.640 --> 45:51.520 + Dawn Bench, and fast AI's achievement on it? + +45:51.520 --> 45:51.960 + Sure. + +45:51.960 --> 45:55.560 + So something which I really enjoy is that I basically + +45:55.560 --> 45:59.000 + teach two courses a year, the practical deep learning + +45:59.000 --> 46:02.120 + for coders, which is kind of the introductory course, + +46:02.120 --> 46:04.280 + and then cutting edge deep learning for coders, which + +46:04.280 --> 46:08.080 + is the kind of research level course. + +46:08.080 --> 46:14.320 + And while I teach those courses, I basically + +46:14.320 --> 46:18.440 + have a big office at the University of San Francisco. + +46:18.440 --> 46:19.800 + It'd be enough for like 30 people. + +46:19.800 --> 46:22.960 + And I invite any student who wants to come and hang out + +46:22.960 --> 46:25.320 + with me while I build the course. + +46:25.320 --> 46:26.640 + And so generally, it's full. + +46:26.640 --> 46:30.880 + And so we have 20 or 30 people in a big office + +46:30.880 --> 46:33.880 + with nothing to do but study deep learning. + +46:33.880 --> 46:35.880 + So it was during one of these times + +46:35.880 --> 46:38.640 + that somebody in the group said, oh, there's + +46:38.640 --> 46:41.480 + a thing called Dawn Bench that looks interesting. + +46:41.480 --> 46:42.800 + And I say, what the hell is that? + +46:42.800 --> 46:44.120 + I'm going to set out some competition + +46:44.120 --> 46:46.440 + to see how quickly you can train a model. + +46:46.440 --> 46:50.080 + It seems kind of not exactly relevant to what we're doing, + +46:50.080 --> 46:51.440 + but it sounds like the kind of thing + +46:51.440 --> 46:52.480 + which you might be interested in. + +46:52.480 --> 46:53.960 + And I checked it out and I was like, oh, crap. + +46:53.960 --> 46:55.840 + There's only 10 days till it's over. + +46:55.840 --> 46:58.120 + It's pretty much too late. + +46:58.120 --> 47:01.000 + And we're kind of busy trying to teach this course. + +47:01.000 --> 47:05.640 + But we're like, oh, it would make an interesting case study + +47:05.640 --> 47:08.200 + for the course like it's all the stuff we're already doing. + +47:08.200 --> 47:11.120 + Why don't we just put together our current best practices + +47:11.120 --> 47:12.480 + and ideas. + +47:12.480 --> 47:16.880 + So me and I guess about four students just decided + +47:16.880 --> 47:17.560 + to give it a go. + +47:17.560 --> 47:19.880 + And we focused on this small one called + +47:19.880 --> 47:24.640 + SciFar 10, which is little 32 by 32 pixel images. + +47:24.640 --> 47:26.160 + Can you say what Dawn Bench is? + +47:26.160 --> 47:29.560 + Yeah, so it's a competition to train a model as fast as possible. + +47:29.560 --> 47:31.000 + It was run by Stanford. + +47:31.000 --> 47:32.480 + And as cheap as possible, too. + +47:32.480 --> 47:34.320 + That's also another one for as cheap as possible. + +47:34.320 --> 47:38.160 + And there's a couple of categories, ImageNet and SciFar 10. + +47:38.160 --> 47:42.080 + So ImageNet's this big 1.3 million image thing + +47:42.080 --> 47:45.400 + that took a couple of days to train. + +47:45.400 --> 47:51.240 + I remember a friend of mine, Pete Warden, who's now at Google. + +47:51.240 --> 47:53.760 + I remember he told me how he trained ImageNet a few years + +47:53.760 --> 47:59.440 + ago when he basically had this little granny flat out + +47:59.440 --> 48:01.920 + the back that he turned into was ImageNet training center. + +48:01.920 --> 48:04.240 + And after a year of work, he figured out + +48:04.240 --> 48:07.040 + how to train it in 10 days or something. + +48:07.040 --> 48:08.480 + It's like that was a big job. + +48:08.480 --> 48:10.640 + Whereas SciFar 10, at that time, you + +48:10.640 --> 48:13.040 + could train in a few hours. + +48:13.040 --> 48:14.520 + It's much smaller and easier. + +48:14.520 --> 48:18.120 + So we thought we'd try SciFar 10. + +48:18.120 --> 48:23.800 + And yeah, I've really never done that before. + +48:23.800 --> 48:27.920 + Like, things like using more than one GPU at a time + +48:27.920 --> 48:29.800 + was something I tried to avoid. + +48:29.800 --> 48:32.160 + Because to me, it's very against the whole idea + +48:32.160 --> 48:35.080 + of accessibility, is she better do things with one GPU? + +48:35.080 --> 48:36.480 + I mean, have you asked in the past + +48:36.480 --> 48:39.680 + before, after having accomplished something, + +48:39.680 --> 48:42.520 + how do I do this faster, much faster? + +48:42.520 --> 48:43.240 + Oh, always. + +48:43.240 --> 48:44.680 + But it's always, for me, it's always, + +48:44.680 --> 48:47.640 + how do I make it much faster on a single GPU + +48:47.640 --> 48:50.400 + that a normal person could afford in their day to day life? + +48:50.400 --> 48:54.760 + It's not, how could I do it faster by having a huge data + +48:54.760 --> 48:55.280 + center? + +48:55.280 --> 48:57.240 + Because to me, it's all about, like, + +48:57.240 --> 48:59.560 + as many people should be able to use something as possible + +48:59.560 --> 49:04.160 + without fussing around with infrastructure. + +49:04.160 --> 49:06.080 + So anyway, so in this case, it's like, well, + +49:06.080 --> 49:10.240 + we can use 8GPUs just by renting a AWS machine. + +49:10.240 --> 49:11.920 + So we thought we'd try that. + +49:11.920 --> 49:16.560 + And yeah, basically, using the stuff we were already doing, + +49:16.560 --> 49:20.360 + we were able to get the speed. + +49:20.360 --> 49:25.360 + Within a few days, we had the speed down to a very small + +49:25.360 --> 49:26.040 + number of minutes. + +49:26.040 --> 49:28.800 + I can't remember exactly how many minutes it was, + +49:28.800 --> 49:31.440 + but it might have been like 10 minutes or something. + +49:31.440 --> 49:34.200 + And so yeah, we found ourselves at the top of the leaderboard + +49:34.200 --> 49:38.720 + easily for both time and money, which really shocked me. + +49:38.720 --> 49:40.160 + Because the other people competing in this + +49:40.160 --> 49:41.880 + were like Google and Intel and stuff, + +49:41.880 --> 49:45.360 + where I know a lot more about this stuff than I think we do. + +49:45.360 --> 49:46.800 + So then we emboldened. + +49:46.800 --> 49:50.640 + We thought, let's try the ImageNet one too. + +49:50.640 --> 49:53.280 + I mean, it seemed way out of our league. + +49:53.280 --> 49:57.120 + But our goal was to get under 12 hours. + +49:57.120 --> 49:59.280 + And we did, which was really exciting. + +49:59.280 --> 50:01.440 + And we didn't put anything up on the leaderboard, + +50:01.440 --> 50:03.080 + but we were down to like 10 hours. + +50:03.080 --> 50:10.000 + But then Google put in like five hours or something, + +50:10.000 --> 50:13.360 + and we're just like, oh, we're so screwed. + +50:13.360 --> 50:16.880 + But we kind of thought, well, keep trying. + +50:16.880 --> 50:17.880 + If Google can do it in five hours. + +50:17.880 --> 50:20.760 + I mean, Google did it on five hours on like a TPU pod + +50:20.760 --> 50:24.280 + or something, like a lot of hardware. + +50:24.280 --> 50:26.360 + But we kind of like had a bunch of ideas to try. + +50:26.360 --> 50:28.920 + Like a really simple thing was, why + +50:28.920 --> 50:30.480 + are we using these big images? + +50:30.480 --> 50:36.280 + They're like 224, 256 by 256 pixels. + +50:36.280 --> 50:37.640 + Why don't we try smaller ones? + +50:37.640 --> 50:41.360 + And just to elaborate, there's a constraint on the accuracy + +50:41.360 --> 50:43.080 + that your train model is supposed to achieve. + +50:43.080 --> 50:45.760 + Yeah, you've got to achieve 93%. + +50:45.760 --> 50:47.640 + I think it was for ImageNet. + +50:47.640 --> 50:49.160 + Exactly. + +50:49.160 --> 50:50.240 + Which is very tough. + +50:50.240 --> 50:51.240 + So you have to repeat that. + +50:51.240 --> 50:52.120 + Yeah, 93%. + +50:52.120 --> 50:54.680 + Like they picked a good threshold. + +50:54.680 --> 50:58.920 + It was a little bit higher than what the most commonly used + +50:58.920 --> 51:03.320 + ResNet 50 model could achieve at that time. + +51:03.320 --> 51:08.080 + So yeah, so it's quite a difficult problem to solve. + +51:08.080 --> 51:09.920 + But yeah, we realized if we actually just + +51:09.920 --> 51:16.200 + use 64 by 64 images, it trained a pretty good model. + +51:16.200 --> 51:17.960 + And then we could take that same model + +51:17.960 --> 51:19.560 + and just give it a couple of epochs + +51:19.560 --> 51:21.880 + to learn 224 by 224 images. + +51:21.880 --> 51:24.440 + And it was basically already trained. + +51:24.440 --> 51:25.480 + It makes a lot of sense. + +51:25.480 --> 51:27.200 + Like if you teach somebody, like here's + +51:27.200 --> 51:30.240 + what a dog looks like, and you show them low res versions, + +51:30.240 --> 51:33.640 + and then you say, here's a really clear picture of a dog. + +51:33.640 --> 51:36.000 + They already know what a dog looks like. + +51:36.000 --> 51:39.920 + So that, like, just we jumped to the front, + +51:39.920 --> 51:46.400 + and we ended up winning parts of that competition. + +51:46.400 --> 51:49.680 + We actually ended up doing a distributed version + +51:49.680 --> 51:51.960 + over multiple machines a couple of months later + +51:51.960 --> 51:53.560 + and ended up at the top of the leaderboard. + +51:53.560 --> 51:55.440 + We had 18 minutes. + +51:55.440 --> 51:56.280 + ImageNet. + +51:56.280 --> 52:00.560 + Yeah, and people have just kept on blasting through again + +52:00.560 --> 52:02.320 + and again since then. + +52:02.320 --> 52:06.760 + So what's your view on multi GPU or multiple machine + +52:06.760 --> 52:11.960 + training in general as a way to speed code up? + +52:11.960 --> 52:13.680 + I think it's largely a waste of time. + +52:13.680 --> 52:15.880 + Both multi GPU on a single machine and? + +52:15.880 --> 52:17.640 + Yeah, particularly multi machines, + +52:17.640 --> 52:18.880 + because it's just clunky. + +52:21.840 --> 52:25.320 + Multi GPUs is less clunky than it used to be. + +52:25.320 --> 52:28.520 + But to me, anything that slows down your iteration speed + +52:28.520 --> 52:31.800 + is a waste of time. + +52:31.800 --> 52:36.960 + So you could maybe do your very last perfecting of the model + +52:36.960 --> 52:38.960 + on multi GPUs if you need to. + +52:38.960 --> 52:44.560 + But so for example, I think doing stuff on ImageNet + +52:44.560 --> 52:46.000 + is generally a waste of time. + +52:46.000 --> 52:48.240 + Why test things on 1.3 million images? + +52:48.240 --> 52:51.040 + Most of us don't use 1.3 million images. + +52:51.040 --> 52:54.360 + And we've also done research that shows that doing things + +52:54.360 --> 52:56.840 + on a smaller subset of images gives you + +52:56.840 --> 52:59.280 + the same relative answers anyway. + +52:59.280 --> 53:02.120 + So from a research point of view, why waste that time? + +53:02.120 --> 53:06.200 + So actually, I released a couple of new data sets recently. + +53:06.200 --> 53:08.880 + One is called ImageNet. + +53:08.880 --> 53:12.920 + The French ImageNet, which is a small subset of ImageNet, + +53:12.920 --> 53:15.200 + which is designed to be easy to classify. + +53:15.200 --> 53:17.320 + What's how do you spell ImageNet? + +53:17.320 --> 53:19.200 + It's got an extra T and E at the end, + +53:19.200 --> 53:20.520 + because it's very French. + +53:20.520 --> 53:21.640 + Image, OK. + +53:21.640 --> 53:24.720 + And then another one called ImageWolf, + +53:24.720 --> 53:29.840 + which is a subset of ImageNet that only contains dog breeds. + +53:29.840 --> 53:31.120 + But that's a hard one, right? + +53:31.120 --> 53:32.000 + That's a hard one. + +53:32.000 --> 53:34.360 + And I've discovered that if you just look at these two + +53:34.360 --> 53:39.120 + subsets, you can train things on a single GPU in 10 minutes. + +53:39.120 --> 53:42.040 + And the results you get are directly transferrable + +53:42.040 --> 53:44.320 + to ImageNet nearly all the time. + +53:44.320 --> 53:46.600 + And so now I'm starting to see some researchers start + +53:46.600 --> 53:48.960 + to use these smaller data sets. + +53:48.960 --> 53:51.120 + I so deeply love the way you think, + +53:51.120 --> 53:57.000 + because I think you might have written a blog post saying + +53:57.000 --> 54:00.200 + that going with these big data sets + +54:00.200 --> 54:03.920 + is encouraging people to not think creatively. + +54:03.920 --> 54:04.560 + Absolutely. + +54:04.560 --> 54:08.320 + So year two, it sort of constrains you + +54:08.320 --> 54:09.840 + to train on large resources. + +54:09.840 --> 54:11.280 + And because you have these resources, + +54:11.280 --> 54:14.040 + you think more research will be better. + +54:14.040 --> 54:17.760 + And then you start to like somehow you kill the creativity. + +54:17.760 --> 54:18.000 + Yeah. + +54:18.000 --> 54:20.760 + And even worse than that, Lex, I keep hearing from people + +54:20.760 --> 54:23.480 + who say, I decided not to get into deep learning + +54:23.480 --> 54:26.080 + because I don't believe it's accessible to people + +54:26.080 --> 54:28.560 + outside of Google to do useful work. + +54:28.560 --> 54:31.640 + So like I see a lot of people make an explicit decision + +54:31.640 --> 54:36.000 + to not learn this incredibly valuable tool + +54:36.000 --> 54:39.840 + because they've drunk the Google Kool Aid, which is that only + +54:39.840 --> 54:42.440 + Google's big enough and smart enough to do it. + +54:42.440 --> 54:45.400 + And I just find that so disappointing and it's so wrong. + +54:45.400 --> 54:49.200 + And I think all of the major breakthroughs in AI + +54:49.200 --> 54:53.280 + in the next 20 years will be doable on a single GPU. + +54:53.280 --> 54:57.120 + Like I would say, my sense is all the big sort of. + +54:57.120 --> 54:58.200 + Well, let's put it this way. + +54:58.200 --> 55:00.200 + None of the big breakthroughs of the last 20 years + +55:00.200 --> 55:01.720 + have required multiple GPUs. + +55:01.720 --> 55:05.920 + So like batch norm, value, dropout, + +55:05.920 --> 55:08.080 + to demonstrate that there's something to them. + +55:08.080 --> 55:11.840 + Every one of them, none of them has required multiple GPUs. + +55:11.840 --> 55:15.800 + GANs, the original GANs, didn't require multiple GPUs. + +55:15.800 --> 55:18.040 + Well, and we've actually recently shown + +55:18.040 --> 55:19.680 + that you don't even need GANs. + +55:19.680 --> 55:23.360 + So we've developed GAN level outcomes + +55:23.360 --> 55:24.720 + without needing GANs. + +55:24.720 --> 55:26.880 + And we can now do it with, again, + +55:26.880 --> 55:29.680 + by using transfer learning, we can do it in a couple of hours + +55:29.680 --> 55:30.520 + on a single GPU. + +55:30.520 --> 55:31.600 + So you're using a generator model + +55:31.600 --> 55:32.960 + without the adversarial part? + +55:32.960 --> 55:33.440 + Yeah. + +55:33.440 --> 55:35.880 + So we've found loss functions that + +55:35.880 --> 55:38.680 + work super well without the adversarial part. + +55:38.680 --> 55:41.840 + And then one of our students, a guy called Jason Antich, + +55:41.840 --> 55:44.640 + has created a system called Dealtify, + +55:44.640 --> 55:47.280 + which uses this technique to colorize + +55:47.280 --> 55:48.840 + old black and white movies. + +55:48.840 --> 55:51.480 + You can do it on a single GPU, colorize a whole movie + +55:51.480 --> 55:52.920 + in a couple of hours. + +55:52.920 --> 55:56.080 + And one of the things that Jason and I did together + +55:56.080 --> 56:00.480 + was we figured out how to add a little bit of GAN + +56:00.480 --> 56:03.000 + at the very end, which it turns out for colorization, + +56:03.000 --> 56:06.000 + makes it just a bit brighter and nicer. + +56:06.000 --> 56:07.920 + And then Jason did masses of experiments + +56:07.920 --> 56:10.000 + to figure out exactly how much to do. + +56:10.000 --> 56:12.840 + But it's still all done on his home machine, + +56:12.840 --> 56:15.400 + on a single GPU in his lounge room. + +56:15.400 --> 56:19.200 + And if you think about colorizing Hollywood movies, + +56:19.200 --> 56:21.720 + that sounds like something a huge studio would have to do. + +56:21.720 --> 56:25.280 + But he has the world's best results on this. + +56:25.280 --> 56:27.040 + There's this problem of microphones. + +56:27.040 --> 56:28.640 + We're just talking to microphones now. + +56:28.640 --> 56:29.140 + Yeah. + +56:29.140 --> 56:32.520 + It's such a pain in the ass to have these microphones + +56:32.520 --> 56:34.440 + to get good quality audio. + +56:34.440 --> 56:36.720 + And I tried to see if it's possible to plop down + +56:36.720 --> 56:39.960 + a bunch of cheap sensors and reconstruct higher quality + +56:39.960 --> 56:41.840 + audio from multiple sources. + +56:41.840 --> 56:45.440 + Because right now, I haven't seen work from, OK, + +56:45.440 --> 56:48.760 + we can save inexpensive mics, automatically combining + +56:48.760 --> 56:52.280 + audio from multiple sources to improve the combined audio. + +56:52.280 --> 56:53.200 + People haven't done that. + +56:53.200 --> 56:55.080 + And that feels like a learning problem. + +56:55.080 --> 56:56.800 + So hopefully somebody can. + +56:56.800 --> 56:58.760 + Well, I mean, it's evidently doable. + +56:58.760 --> 57:01.000 + And it should have been done by now. + +57:01.000 --> 57:03.640 + I felt the same way about computational photography + +57:03.640 --> 57:04.480 + four years ago. + +57:04.480 --> 57:05.240 + That's right. + +57:05.240 --> 57:08.240 + Why are we investing in big lenses when + +57:08.240 --> 57:13.160 + three cheap lenses plus actually a little bit of intentional + +57:13.160 --> 57:16.640 + movement, so like take a few frames, + +57:16.640 --> 57:19.840 + gives you enough information to get excellent subpixel + +57:19.840 --> 57:22.440 + resolution, which particularly with deep learning, + +57:22.440 --> 57:25.840 + you would know exactly what you meant to be looking at. + +57:25.840 --> 57:28.200 + We can totally do the same thing with audio. + +57:28.200 --> 57:30.720 + I think the madness that it hasn't been done yet. + +57:30.720 --> 57:33.320 + Has there been progress on photography companies? + +57:33.320 --> 57:33.820 + Yeah. + +57:33.820 --> 57:36.720 + Photography is basically a standard now. + +57:36.720 --> 57:41.120 + So the Google Pixel Nightlight, I + +57:41.120 --> 57:43.240 + don't know if you've ever tried it, but it's astonishing. + +57:43.240 --> 57:45.440 + You take a picture and almost pitch black + +57:45.440 --> 57:49.120 + and you get back a very high quality image. + +57:49.120 --> 57:51.440 + And it's not because of the lens. + +57:51.440 --> 57:55.280 + Same stuff with like adding the bokeh to the background + +57:55.280 --> 57:55.800 + blurring. + +57:55.800 --> 57:57.200 + It's done computationally. + +57:57.200 --> 57:58.520 + Just the pics over here. + +57:58.520 --> 57:59.020 + Yeah. + +57:59.020 --> 58:05.000 + Basically, everybody now is doing most of the fanciest stuff + +58:05.000 --> 58:07.120 + on their phones with computational photography + +58:07.120 --> 58:10.640 + and also increasingly, people are putting more than one lens + +58:10.640 --> 58:11.840 + on the back of the camera. + +58:11.840 --> 58:14.360 + So the same will happen for audio, for sure. + +58:14.360 --> 58:16.520 + And there's applications in the audio side. + +58:16.520 --> 58:19.360 + If you look at an Alexa type device, + +58:19.360 --> 58:21.840 + most people I've seen, especially I worked at Google + +58:21.840 --> 58:26.000 + before, when you look at noise background removal, + +58:26.000 --> 58:29.480 + you don't think of multiple sources of audio. + +58:29.480 --> 58:31.920 + You don't play with that as much as I would hope people would. + +58:31.920 --> 58:33.640 + But I mean, you can still do it even with one. + +58:33.640 --> 58:36.120 + Like, again, it's not much work's been done in this area. + +58:36.120 --> 58:38.440 + So we're actually going to be releasing an audio library + +58:38.440 --> 58:41.040 + soon, which hopefully will encourage development of this + +58:41.040 --> 58:43.200 + because it's so underused. + +58:43.200 --> 58:46.480 + The basic approach we used for our super resolution, + +58:46.480 --> 58:49.960 + in which Jason uses for dealdify of generating + +58:49.960 --> 58:51.920 + high quality images, the exact same approach + +58:51.920 --> 58:53.480 + would work for audio. + +58:53.480 --> 58:57.160 + No one's done it yet, but it would be a couple of months work. + +58:57.160 --> 59:01.600 + OK, also learning rate in terms of dawn bench. + +59:01.600 --> 59:04.280 + There's some magic on learning rate that you played around + +59:04.280 --> 59:04.760 + with. + +59:04.760 --> 59:05.800 + It's kind of interesting. + +59:05.800 --> 59:08.120 + Yeah, so this is all work that came from a guy called Leslie + +59:08.120 --> 59:09.360 + Smith. + +59:09.360 --> 59:12.760 + Leslie's a researcher who, like us, + +59:12.760 --> 59:17.720 + cares a lot about just the practicalities of training + +59:17.720 --> 59:20.000 + neural networks quickly and accurately, + +59:20.000 --> 59:22.120 + which you would think is what everybody should care about, + +59:22.120 --> 59:25.000 + but almost nobody does. + +59:25.000 --> 59:28.120 + And he discovered something very interesting, + +59:28.120 --> 59:30.000 + which he calls super convergence, which + +59:30.000 --> 59:32.360 + is there are certain networks that with certain settings + +59:32.360 --> 59:34.320 + of high parameters could suddenly + +59:34.320 --> 59:37.440 + be trained 10 times faster by using + +59:37.440 --> 59:39.480 + a 10 times higher learning rate. + +59:39.480 --> 59:44.680 + Now, no one published that paper + +59:44.680 --> 59:49.520 + because it's not an area of active research + +59:49.520 --> 59:50.440 + in the academic world. + +59:50.440 --> 59:52.840 + No academics recognize this is important. + +59:52.840 --> 59:56.080 + And also, deep learning in academia + +59:56.080 --> 1:00:00.040 + is not considered a experimental science. + +1:00:00.040 --> 1:00:02.440 + So unlike in physics, where you could say, + +1:00:02.440 --> 1:00:05.360 + I just saw a subatomic particle do something + +1:00:05.360 --> 1:00:07.240 + which the theory doesn't explain, + +1:00:07.240 --> 1:00:10.440 + you could publish that without an explanation. + +1:00:10.440 --> 1:00:12.120 + And then in the next 60 years, people + +1:00:12.120 --> 1:00:14.120 + can try to work out how to explain it. + +1:00:14.120 --> 1:00:16.200 + We don't allow this in the deep learning world. + +1:00:16.200 --> 1:00:20.720 + So it's literally impossible for Leslie to publish a paper that + +1:00:20.720 --> 1:00:23.560 + says, I've just seen something amazing happen. + +1:00:23.560 --> 1:00:25.680 + This thing trained 10 times faster than it should have. + +1:00:25.680 --> 1:00:27.080 + I don't know why. + +1:00:27.080 --> 1:00:28.600 + And so the reviewers were like, well, + +1:00:28.600 --> 1:00:30.280 + you can't publish that because you don't know why. + +1:00:30.280 --> 1:00:31.000 + So anyway. + +1:00:31.000 --> 1:00:32.680 + That's important to pause on because there's + +1:00:32.680 --> 1:00:36.160 + so many discoveries that would need to start like that. + +1:00:36.160 --> 1:00:39.280 + Every other scientific field I know of works of that way. + +1:00:39.280 --> 1:00:42.520 + I don't know why ours is uniquely + +1:00:42.520 --> 1:00:46.480 + disinterested in publishing unexplained + +1:00:46.480 --> 1:00:47.680 + experimental results. + +1:00:47.680 --> 1:00:48.680 + But there it is. + +1:00:48.680 --> 1:00:51.200 + So it wasn't published. + +1:00:51.200 --> 1:00:55.080 + Having said that, I read a lot more + +1:00:55.080 --> 1:00:56.840 + unpublished papers and published papers + +1:00:56.840 --> 1:01:00.080 + because that's where you find the interesting insights. + +1:01:00.080 --> 1:01:02.680 + So I absolutely read this paper. + +1:01:02.680 --> 1:01:08.120 + And I was just like, this is astonishingly mind blowing + +1:01:08.120 --> 1:01:09.760 + and weird and awesome. + +1:01:09.760 --> 1:01:12.400 + And why isn't everybody only talking about this? + +1:01:12.400 --> 1:01:15.520 + Because if you can train these things 10 times faster, + +1:01:15.520 --> 1:01:18.480 + they also generalize better because you're doing less epochs, + +1:01:18.480 --> 1:01:20.080 + which means you look at the data less, + +1:01:20.080 --> 1:01:22.400 + you get better accuracy. + +1:01:22.400 --> 1:01:24.640 + So I've been kind of studying that ever since. + +1:01:24.640 --> 1:01:28.520 + And eventually Leslie kind of figured out + +1:01:28.520 --> 1:01:30.160 + a lot of how to get this done. + +1:01:30.160 --> 1:01:32.280 + And we added minor tweaks. + +1:01:32.280 --> 1:01:34.840 + And a big part of the trick is starting + +1:01:34.840 --> 1:01:37.920 + at a very low learning rate, very gradually increasing it. + +1:01:37.920 --> 1:01:39.800 + So as you're training your model, + +1:01:39.800 --> 1:01:42.120 + you take very small steps at the start. + +1:01:42.120 --> 1:01:44.080 + And you gradually make them bigger and bigger + +1:01:44.080 --> 1:01:46.440 + until eventually you're taking much bigger steps + +1:01:46.440 --> 1:01:49.400 + than anybody thought was possible. + +1:01:49.400 --> 1:01:52.280 + There's a few other little tricks to make it work. + +1:01:52.280 --> 1:01:55.240 + Basically, we can reliably get super convergence. + +1:01:55.240 --> 1:01:56.640 + And so for the dorm bench thing, + +1:01:56.640 --> 1:01:59.320 + we were using just much higher learning rates + +1:01:59.320 --> 1:02:02.200 + than people expected to work. + +1:02:02.200 --> 1:02:03.880 + What do you think the future of, + +1:02:03.880 --> 1:02:05.200 + I mean, it makes so much sense for that + +1:02:05.200 --> 1:02:08.640 + to be a critical hyperparameter learning rate that you vary. + +1:02:08.640 --> 1:02:13.480 + What do you think the future of learning rate magic looks like? + +1:02:13.480 --> 1:02:14.960 + Well, there's been a lot of great work + +1:02:14.960 --> 1:02:17.400 + in the last 12 months in this area. + +1:02:17.400 --> 1:02:20.800 + And people are increasingly realizing that we just + +1:02:20.800 --> 1:02:23.120 + have no idea really how optimizers work. + +1:02:23.120 --> 1:02:25.840 + And the combination of weight decay, + +1:02:25.840 --> 1:02:27.480 + which is how we regularize optimizers, + +1:02:27.480 --> 1:02:30.120 + and the learning rate, and then other things + +1:02:30.120 --> 1:02:32.760 + like the epsilon we use in the atom optimizer, + +1:02:32.760 --> 1:02:36.560 + they all work together in weird ways. + +1:02:36.560 --> 1:02:38.560 + And different parts of the model, + +1:02:38.560 --> 1:02:40.480 + this is another thing we've done a lot of work on, + +1:02:40.480 --> 1:02:43.480 + is research into how different parts of the model + +1:02:43.480 --> 1:02:46.600 + should be trained at different rates in different ways. + +1:02:46.600 --> 1:02:49.040 + So we do something we call discriminative learning rates, + +1:02:49.040 --> 1:02:51.040 + which is really important, particularly for transfer + +1:02:51.040 --> 1:02:53.200 + learning. + +1:02:53.200 --> 1:02:54.880 + So really, I think in the last 12 months, + +1:02:54.880 --> 1:02:57.360 + a lot of people have realized that all this stuff is important. + +1:02:57.360 --> 1:03:00.000 + There's been a lot of great work coming out. + +1:03:00.000 --> 1:03:02.880 + And we're starting to see algorithms + +1:03:02.880 --> 1:03:06.880 + appear which have very, very few dials, if any, + +1:03:06.880 --> 1:03:07.920 + that you have to touch. + +1:03:07.920 --> 1:03:09.240 + So I think what's going to happen + +1:03:09.240 --> 1:03:10.840 + is the idea of a learning rate, well, + +1:03:10.840 --> 1:03:14.360 + it almost already has disappeared in the latest research. + +1:03:14.360 --> 1:03:18.240 + And instead, it's just like, we know enough + +1:03:18.240 --> 1:03:22.440 + about how to interpret the gradients + +1:03:22.440 --> 1:03:23.840 + and the change of gradients we see + +1:03:23.840 --> 1:03:25.440 + to know how to set every parameter of our way. + +1:03:25.440 --> 1:03:26.440 + There you can automate it. + +1:03:26.440 --> 1:03:31.720 + So you see the future of deep learning, where really, + +1:03:31.720 --> 1:03:34.600 + where is the input of a human expert needed? + +1:03:34.600 --> 1:03:36.520 + Well, hopefully, the input of a human expert + +1:03:36.520 --> 1:03:39.680 + will be almost entirely unneeded from the deep learning + +1:03:39.680 --> 1:03:40.560 + point of view. + +1:03:40.560 --> 1:03:43.480 + So again, Google's approach to this + +1:03:43.480 --> 1:03:46.000 + is to try and use thousands of times more compute + +1:03:46.000 --> 1:03:49.400 + to run lots and lots of models at the same time + +1:03:49.400 --> 1:03:51.040 + and hope that one of them is good. + +1:03:51.040 --> 1:03:51.960 + A lot of malkana stuff. + +1:03:51.960 --> 1:03:56.800 + Yeah, a lot of malkana stuff, which I think is insane. + +1:03:56.800 --> 1:04:01.720 + When you better understand the mechanics of how models learn, + +1:04:01.720 --> 1:04:03.800 + you don't have to try 1,000 different models + +1:04:03.800 --> 1:04:05.680 + to find which one happens to work the best. + +1:04:05.680 --> 1:04:08.240 + You can just jump straight to the best one, which + +1:04:08.240 --> 1:04:12.720 + means that it's more accessible in terms of compute, cheaper, + +1:04:12.720 --> 1:04:14.920 + and also with less hyperparameters to set. + +1:04:14.920 --> 1:04:16.800 + That means you don't need deep learning experts + +1:04:16.800 --> 1:04:19.360 + to train your deep learning model for you, + +1:04:19.360 --> 1:04:22.480 + which means that domain experts can do more of the work, which + +1:04:22.480 --> 1:04:24.960 + means that now you can focus the human time + +1:04:24.960 --> 1:04:28.320 + on the kind of interpretation, the data gathering, + +1:04:28.320 --> 1:04:31.360 + identifying model errors, and stuff like that. + +1:04:31.360 --> 1:04:32.840 + Yeah, the data side. + +1:04:32.840 --> 1:04:34.720 + How often do you work with data these days + +1:04:34.720 --> 1:04:38.680 + in terms of the cleaning, Darwin looked + +1:04:38.680 --> 1:04:43.120 + at different species while traveling about, + +1:04:43.120 --> 1:04:45.040 + do you look at data? + +1:04:45.040 --> 1:04:49.400 + Have you, in your roots in Kaggle, just look at data? + +1:04:49.400 --> 1:04:51.320 + Yeah, I mean, it's a key part of our course. + +1:04:51.320 --> 1:04:53.480 + It's like before we train a model in the course, + +1:04:53.480 --> 1:04:55.160 + we see how to look at the data. + +1:04:55.160 --> 1:04:57.920 + And then the first thing we do after we train our first model, + +1:04:57.920 --> 1:05:00.520 + which we fine tune an ImageNet model for five minutes. + +1:05:00.520 --> 1:05:02.240 + And then the thing we immediately do after that + +1:05:02.240 --> 1:05:05.760 + is we learn how to analyze the results of the model + +1:05:05.760 --> 1:05:08.920 + by looking at examples of misclassified images, + +1:05:08.920 --> 1:05:10.880 + and looking at a classification matrix, + +1:05:10.880 --> 1:05:15.080 + and then doing research on Google + +1:05:15.080 --> 1:05:18.000 + to learn about the kinds of things that it's misclassifying. + +1:05:18.000 --> 1:05:19.520 + So to me, one of the really cool things + +1:05:19.520 --> 1:05:21.840 + about machine learning models in general + +1:05:21.840 --> 1:05:24.480 + is that when you interpret them, they + +1:05:24.480 --> 1:05:27.360 + tell you about things like what are the most important features, + +1:05:27.360 --> 1:05:29.400 + which groups you're misclassifying, + +1:05:29.400 --> 1:05:32.440 + and they help you become a domain expert more quickly, + +1:05:32.440 --> 1:05:34.880 + because you can focus your time on the bits + +1:05:34.880 --> 1:05:38.680 + that the model is telling you is important. + +1:05:38.680 --> 1:05:40.760 + So it lets you deal with things like data leakage, + +1:05:40.760 --> 1:05:43.080 + for example, if it says, oh, the main feature I'm looking at + +1:05:43.080 --> 1:05:45.240 + is customer ID. + +1:05:45.240 --> 1:05:47.640 + And you're like, oh, customer ID should be predictive. + +1:05:47.640 --> 1:05:52.280 + And then you can talk to the people that manage customer IDs, + +1:05:52.280 --> 1:05:56.840 + and they'll tell you, oh, yes, as soon as a customer's application + +1:05:56.840 --> 1:05:59.480 + is accepted, we add a one on the end of their customer ID + +1:05:59.480 --> 1:06:01.200 + or something. + +1:06:01.200 --> 1:06:04.360 + So yeah, looking at data, particularly + +1:06:04.360 --> 1:06:06.600 + from the lens of which parts of the data the model says + +1:06:06.600 --> 1:06:09.400 + is important, is super important. + +1:06:09.400 --> 1:06:11.480 + Yeah, and using kind of using the model + +1:06:11.480 --> 1:06:14.240 + to almost debug the data to learn more about the data. + +1:06:14.240 --> 1:06:16.800 + Exactly. + +1:06:16.800 --> 1:06:18.600 + What are the different cloud options + +1:06:18.600 --> 1:06:20.160 + for training your networks? + +1:06:20.160 --> 1:06:22.000 + Last question related to Don Bench. + +1:06:22.000 --> 1:06:24.240 + Well, it's part of a lot of the work you do, + +1:06:24.240 --> 1:06:27.280 + but from a perspective of performance, + +1:06:27.280 --> 1:06:29.480 + I think you've written this in a blog post. + +1:06:29.480 --> 1:06:32.720 + There's AWS, there's a TPU from Google. + +1:06:32.720 --> 1:06:33.440 + What's your sense? + +1:06:33.440 --> 1:06:34.520 + What the future holds? + +1:06:34.520 --> 1:06:37.360 + What would you recommend now in terms of training in the cloud? + +1:06:37.360 --> 1:06:40.520 + So from a hardware point of view, + +1:06:40.520 --> 1:06:45.520 + Google's TPUs and the best Nvidia GPUs are similar. + +1:06:45.520 --> 1:06:47.880 + And maybe the TPUs are like 30% faster, + +1:06:47.880 --> 1:06:51.160 + but they're also much harder to program. + +1:06:51.160 --> 1:06:54.720 + There isn't a clear leader in terms of hardware right now, + +1:06:54.720 --> 1:06:57.840 + although much more importantly, the Nvidia's GPUs + +1:06:57.840 --> 1:06:59.560 + are much more programmable. + +1:06:59.560 --> 1:07:01.280 + They've got much more written problems. + +1:07:01.280 --> 1:07:03.480 + That's the clear leader for me and where + +1:07:03.480 --> 1:07:08.640 + I would spend my time as a researcher and practitioner. + +1:07:08.640 --> 1:07:12.280 + But then in terms of the platform, + +1:07:12.280 --> 1:07:15.680 + I mean, we're super lucky now with stuff like Google, + +1:07:15.680 --> 1:07:21.520 + GCP, Google Cloud, and AWS that you can access a GPU + +1:07:21.520 --> 1:07:25.440 + pretty quickly and easily. + +1:07:25.440 --> 1:07:28.280 + But I mean, for AWS, it's still too hard. + +1:07:28.280 --> 1:07:33.760 + You have to find an AMI and get the instance running + +1:07:33.760 --> 1:07:37.080 + and then install the software you want and blah, blah, blah. + +1:07:37.080 --> 1:07:40.400 + GCP is currently the best way to get + +1:07:40.400 --> 1:07:42.320 + started on a full server environment + +1:07:42.320 --> 1:07:46.120 + because they have a fantastic fast AI in PyTorch, + +1:07:46.120 --> 1:07:51.120 + ready to go instance, which has all the courses preinstalled. + +1:07:51.120 --> 1:07:53.040 + It has Jupyter Notebook prerunning. + +1:07:53.040 --> 1:07:57.080 + Jupyter Notebook is this wonderful interactive computing + +1:07:57.080 --> 1:07:59.440 + system, which everybody basically + +1:07:59.440 --> 1:08:02.920 + should be using for any kind of data driven research. + +1:08:02.920 --> 1:08:05.880 + But then even better than that, there + +1:08:05.880 --> 1:08:09.560 + are platforms like Salamander, which we own, + +1:08:09.560 --> 1:08:13.600 + and Paperspace, where literally you click a single button + +1:08:13.600 --> 1:08:17.240 + and it pops up and you put a notebook straight away + +1:08:17.240 --> 1:08:22.240 + without any kind of installation or anything. + +1:08:22.240 --> 1:08:25.800 + And all the course notebooks are all preinstalled. + +1:08:25.800 --> 1:08:28.560 + So for me, this is one of the things + +1:08:28.560 --> 1:08:34.160 + we spent a lot of time curating and working on. + +1:08:34.160 --> 1:08:35.960 + Because when we first started our courses, + +1:08:35.960 --> 1:08:39.560 + the biggest problem was people dropped out of lesson one + +1:08:39.560 --> 1:08:42.680 + because they couldn't get an AWS instance running. + +1:08:42.680 --> 1:08:44.880 + So things are so much better now. + +1:08:44.880 --> 1:08:47.760 + And we actually have, if you go to course.fast.ai, + +1:08:47.760 --> 1:08:49.040 + the first thing it says is, here's + +1:08:49.040 --> 1:08:50.480 + how to get started with your GPU. + +1:08:50.480 --> 1:08:52.120 + And it's like, you just click on the link + +1:08:52.120 --> 1:08:55.120 + and you click start and you're going. + +1:08:55.120 --> 1:08:56.240 + You will go GCP. + +1:08:56.240 --> 1:08:58.760 + I have to confess, I've never used the Google GCP. + +1:08:58.760 --> 1:09:01.600 + Yeah, GCP gives you $300 of compute for free, + +1:09:01.600 --> 1:09:04.920 + which is really nice. + +1:09:04.920 --> 1:09:10.960 + But as I say, Salamander and Paperspace are even easier still. + +1:09:10.960 --> 1:09:15.120 + So from the perspective of deep learning frameworks, + +1:09:15.120 --> 1:09:18.400 + you work with Fast.ai, if you think of it as framework, + +1:09:18.400 --> 1:09:22.960 + and PyTorch and TensorFlow, what are the strengths + +1:09:22.960 --> 1:09:25.840 + of each platform in your perspective? + +1:09:25.840 --> 1:09:29.240 + So in terms of what we've done our research on and taught + +1:09:29.240 --> 1:09:34.400 + in our course, we started with Theano and Keras. + +1:09:34.400 --> 1:09:38.120 + And then we switched to TensorFlow and Keras. + +1:09:38.120 --> 1:09:40.400 + And then we switched to PyTorch. + +1:09:40.400 --> 1:09:43.360 + And then we switched to PyTorch and Fast.ai. + +1:09:43.360 --> 1:09:47.560 + And that kind of reflects a growth and development + +1:09:47.560 --> 1:09:52.560 + of the ecosystem of deep learning libraries. + +1:09:52.560 --> 1:09:57.040 + Theano and TensorFlow were great, + +1:09:57.040 --> 1:10:01.360 + but were much harder to teach and to do research and development + +1:10:01.360 --> 1:10:04.560 + on because they define what's called a computational graph + +1:10:04.560 --> 1:10:06.680 + up front, a static graph, where you basically + +1:10:06.680 --> 1:10:08.360 + have to say, here are all the things + +1:10:08.360 --> 1:10:12.040 + that I'm going to eventually do in my model. + +1:10:12.040 --> 1:10:15.080 + And then later on, you say, OK, do those things with this data. + +1:10:15.080 --> 1:10:17.160 + And you can't debug them. + +1:10:17.160 --> 1:10:18.560 + You can't do them step by step. + +1:10:18.560 --> 1:10:20.160 + You can't program them interactively + +1:10:20.160 --> 1:10:22.280 + in a Jupyter notebook and so forth. + +1:10:22.280 --> 1:10:24.320 + PyTorch was not the first, but PyTorch + +1:10:24.320 --> 1:10:27.400 + was certainly the strongest entrant to come along + +1:10:27.400 --> 1:10:28.720 + and say, let's not do it that way. + +1:10:28.720 --> 1:10:31.320 + Let's just use normal Python. + +1:10:31.320 --> 1:10:32.880 + And everything you know about in Python + +1:10:32.880 --> 1:10:34.000 + is just going to work. + +1:10:34.000 --> 1:10:37.880 + And we'll figure out how to make that run on the GPU + +1:10:37.880 --> 1:10:40.800 + as and when necessary. + +1:10:40.800 --> 1:10:45.120 + That turned out to be a huge leap in terms + +1:10:45.120 --> 1:10:46.800 + of what we could do with our research + +1:10:46.800 --> 1:10:49.720 + and what we could do with our teaching. + +1:10:49.720 --> 1:10:51.160 + Because it wasn't limiting. + +1:10:51.160 --> 1:10:52.760 + Yeah, I mean, it was critical for us + +1:10:52.760 --> 1:10:55.960 + for something like Dawnbench to be able to rapidly try things. + +1:10:55.960 --> 1:10:58.560 + It's just so much harder to be a researcher and practitioner + +1:10:58.560 --> 1:11:00.520 + when you have to do everything upfront + +1:11:00.520 --> 1:11:03.400 + and you can't inspect it. + +1:11:03.400 --> 1:11:07.360 + Problem with PyTorch is it's not at all + +1:11:07.360 --> 1:11:09.360 + accessible to newcomers because you + +1:11:09.360 --> 1:11:11.600 + have to write your own training loop + +1:11:11.600 --> 1:11:15.680 + and manage the gradients and all this stuff. + +1:11:15.680 --> 1:11:17.920 + And it's also not great for researchers + +1:11:17.920 --> 1:11:20.680 + because you're spending your time dealing with all this boiler + +1:11:20.680 --> 1:11:23.920 + plate and overhead rather than thinking about your algorithm. + +1:11:23.920 --> 1:11:27.760 + So we ended up writing this very multi layered API + +1:11:27.760 --> 1:11:31.040 + that at the top level, you can train a state of the art neural + +1:11:31.040 --> 1:11:33.640 + network in three lines of code. + +1:11:33.640 --> 1:11:35.920 + And which talks to an API, which talks to an API, + +1:11:35.920 --> 1:11:38.880 + which talks to an API, which you can dive into at any level + +1:11:38.880 --> 1:11:45.400 + and get progressively closer to the machine levels of control. + +1:11:45.400 --> 1:11:47.480 + And this is the fast AI library. + +1:11:47.480 --> 1:11:51.920 + That's been critical for us and for our students + +1:11:51.920 --> 1:11:54.200 + and for lots of people that have won big learning + +1:11:54.200 --> 1:11:58.560 + competitions with it and written academic papers with it. + +1:11:58.560 --> 1:12:00.680 + It's made a big difference. + +1:12:00.680 --> 1:12:03.960 + We're still limited though by Python. + +1:12:03.960 --> 1:12:05.920 + And particularly this problem with things + +1:12:05.920 --> 1:12:10.640 + like our current neural nets say where you just can't change + +1:12:10.640 --> 1:12:13.320 + things unless you accept it going so slowly + +1:12:13.320 --> 1:12:15.680 + that it's impractical. + +1:12:15.680 --> 1:12:18.320 + So in the latest incarnation of the course + +1:12:18.320 --> 1:12:20.880 + and with some of the research we're now starting to do, + +1:12:20.880 --> 1:12:24.480 + we're starting to do some stuff in Swift. + +1:12:24.480 --> 1:12:28.920 + I think we're three years away from that being + +1:12:28.920 --> 1:12:31.080 + super practical, but I'm in no hurry. + +1:12:31.080 --> 1:12:35.480 + I'm very happy to invest the time to get there. + +1:12:35.480 --> 1:12:38.000 + But with that, we actually already + +1:12:38.000 --> 1:12:41.840 + have a nascent version of the fast AI library for vision + +1:12:41.840 --> 1:12:44.720 + running on Swift and TensorFlow. + +1:12:44.720 --> 1:12:48.040 + Because Python for TensorFlow is not going to cut it. + +1:12:48.040 --> 1:12:49.920 + It's just a disaster. + +1:12:49.920 --> 1:12:54.440 + What they did was they tried to replicate the bits + +1:12:54.440 --> 1:12:56.640 + that people were saying they like about PyTorch, + +1:12:56.640 --> 1:12:59.160 + this kind of interactive computation. + +1:12:59.160 --> 1:13:02.760 + But they didn't actually change their foundational runtime + +1:13:02.760 --> 1:13:03.920 + components. + +1:13:03.920 --> 1:13:06.640 + So they kind of added this like syntax, sugar, + +1:13:06.640 --> 1:13:08.560 + they call TF Eager, TensorFlow Eager, which + +1:13:08.560 --> 1:13:10.880 + makes it look a lot like PyTorch. + +1:13:10.880 --> 1:13:16.400 + But it's 10 times slower than PyTorch to actually do a step. + +1:13:16.400 --> 1:13:19.080 + So because they didn't invest the time + +1:13:19.080 --> 1:13:22.080 + in retooling the foundations because their code base + +1:13:22.080 --> 1:13:23.520 + is so horribly complex. + +1:13:23.520 --> 1:13:25.280 + Yeah, I think it's probably very difficult + +1:13:25.280 --> 1:13:26.440 + to do that kind of rejoining. + +1:13:26.440 --> 1:13:28.680 + Yeah, well, particularly the way TensorFlow was written, + +1:13:28.680 --> 1:13:31.480 + it was written by a lot of people very quickly + +1:13:31.480 --> 1:13:33.320 + in a very disorganized way. + +1:13:33.320 --> 1:13:36.000 + So when you actually look in the code, as I do often, + +1:13:36.000 --> 1:13:38.840 + I'm always just like, oh, god, what were they thinking? + +1:13:38.840 --> 1:13:41.480 + It's just, it's pretty awful. + +1:13:41.480 --> 1:13:47.080 + So I'm really extremely negative about the potential future + +1:13:47.080 --> 1:13:52.120 + for Python TensorFlow that Swift for TensorFlow + +1:13:52.120 --> 1:13:53.760 + can be a different beast altogether. + +1:13:53.760 --> 1:13:57.560 + It can be like, it can basically be a layer on top of MLIR + +1:13:57.560 --> 1:14:02.640 + that takes advantage of all the great compiler stuff + +1:14:02.640 --> 1:14:04.760 + that Swift builds on with LLVM. + +1:14:04.760 --> 1:14:07.040 + And yeah, it could be absolutely. + +1:14:07.040 --> 1:14:10.320 + I think it will be absolutely fantastic. + +1:14:10.320 --> 1:14:11.920 + Well, you're inspiring me to try. + +1:14:11.920 --> 1:14:17.640 + Evan truly felt the pain of TensorFlow 2.0 Python. + +1:14:17.640 --> 1:14:19.040 + It's fine by me. + +1:14:19.040 --> 1:14:21.080 + But of course. + +1:14:21.080 --> 1:14:23.240 + Yeah, I mean, it does the job if you're using + +1:14:23.240 --> 1:14:27.720 + predefined things that somebody's already written. + +1:14:27.720 --> 1:14:29.920 + But if you actually compare, like I've + +1:14:29.920 --> 1:14:33.680 + had to do a lot of stuff with TensorFlow recently, + +1:14:33.680 --> 1:14:35.480 + you actually compare like, I want + +1:14:35.480 --> 1:14:37.360 + to write something from scratch. + +1:14:37.360 --> 1:14:39.040 + And you're like, I just keep finding it's like, oh, + +1:14:39.040 --> 1:14:41.560 + it's running 10 times slower than PyTorch. + +1:14:41.560 --> 1:14:43.800 + So is the biggest cost. + +1:14:43.800 --> 1:14:47.360 + Let's throw running time out the window. + +1:14:47.360 --> 1:14:49.640 + How long it takes you to program? + +1:14:49.640 --> 1:14:51.000 + That's not too different now. + +1:14:51.000 --> 1:14:54.080 + Thanks to TensorFlow Eager, that's not too different. + +1:14:54.080 --> 1:14:58.640 + But because so many things take so long to run, + +1:14:58.640 --> 1:15:00.320 + you wouldn't run it at 10 times slower. + +1:15:00.320 --> 1:15:03.000 + Like, you just go like, oh, this is taking too long. + +1:15:03.000 --> 1:15:04.240 + And also, there's a lot of things + +1:15:04.240 --> 1:15:05.840 + which are just less programmable, + +1:15:05.840 --> 1:15:09.000 + like tf.data, which is the way data processing works + +1:15:09.000 --> 1:15:11.400 + in TensorFlow, is just this big mess. + +1:15:11.400 --> 1:15:13.160 + It's incredibly inefficient. + +1:15:13.160 --> 1:15:14.800 + And they kind of had to write it that way + +1:15:14.800 --> 1:15:19.160 + because of the TPU problems I described earlier. + +1:15:19.160 --> 1:15:24.680 + So I just feel like they've got this huge technical debt, + +1:15:24.680 --> 1:15:27.960 + which they're not going to solve without starting from scratch. + +1:15:27.960 --> 1:15:29.440 + So here's an interesting question then. + +1:15:29.440 --> 1:15:34.720 + If there's a new student starting today, + +1:15:34.720 --> 1:15:37.480 + what would you recommend they use? + +1:15:37.480 --> 1:15:39.160 + Well, I mean, we obviously recommend + +1:15:39.160 --> 1:15:42.760 + FastAI and PyTorch because we teach new students. + +1:15:42.760 --> 1:15:43.960 + And that's what we teach with. + +1:15:43.960 --> 1:15:46.080 + So we would very strongly recommend that + +1:15:46.080 --> 1:15:50.280 + because it will let you get on top of the concepts much + +1:15:50.280 --> 1:15:51.960 + more quickly. + +1:15:51.960 --> 1:15:53.160 + So then you'll become an action. + +1:15:53.160 --> 1:15:56.400 + And you'll also learn the actual state of the art techniques. + +1:15:56.400 --> 1:15:59.240 + So you actually get world class results. + +1:15:59.240 --> 1:16:03.000 + Honestly, it doesn't much matter what library + +1:16:03.000 --> 1:16:09.240 + you learn because switching from Shaina to MXNet to TensorFlow + +1:16:09.240 --> 1:16:12.000 + to PyTorch is going to be a couple of days work + +1:16:12.000 --> 1:16:15.280 + if you long as you understand the foundation as well. + +1:16:15.280 --> 1:16:21.600 + But you think we'll Swift creep in there as a thing + +1:16:21.600 --> 1:16:22.960 + that people start using? + +1:16:22.960 --> 1:16:26.400 + Not for a few years, particularly because Swift + +1:16:26.400 --> 1:16:33.440 + has no data science community, libraries, schooling. + +1:16:33.440 --> 1:16:39.080 + And the Swift community has a total lack of appreciation + +1:16:39.080 --> 1:16:41.040 + and understanding of numeric computing. + +1:16:41.040 --> 1:16:43.640 + So they keep on making stupid decisions. + +1:16:43.640 --> 1:16:47.480 + For years, they've just done dumb things around performance + +1:16:47.480 --> 1:16:50.280 + and prioritization. + +1:16:50.280 --> 1:16:56.360 + That's clearly changing now because the developer of Chris + +1:16:56.360 --> 1:16:59.960 + Lattner is working at Google on Swift for TensorFlow. + +1:16:59.960 --> 1:17:03.200 + So that's a priority. + +1:17:03.200 --> 1:17:05.000 + It'll be interesting to see what happens with Apple + +1:17:05.000 --> 1:17:10.000 + because Apple hasn't shown any sign of caring + +1:17:10.000 --> 1:17:12.960 + about numeric programming in Swift. + +1:17:12.960 --> 1:17:16.600 + So hopefully they'll get off their arse + +1:17:16.600 --> 1:17:18.840 + and start appreciating this because currently all + +1:17:18.840 --> 1:17:24.240 + of their low level libraries are not written in Swift. + +1:17:24.240 --> 1:17:27.640 + They're not particularly Swifty at all, stuff like Core ML. + +1:17:27.640 --> 1:17:30.840 + They're really pretty rubbish. + +1:17:30.840 --> 1:17:32.760 + So yeah, so there's a long way to go. + +1:17:32.760 --> 1:17:35.360 + But at least one nice thing is that Swift for TensorFlow + +1:17:35.360 --> 1:17:40.000 + can actually directly use Python code and Python libraries. + +1:17:40.000 --> 1:17:44.240 + Literally, the entire lesson one notebook of fast AI + +1:17:44.240 --> 1:17:47.800 + runs in Swift right now in Python mode. + +1:17:47.800 --> 1:17:50.800 + So that's a nice intermediate thing. + +1:17:50.800 --> 1:17:56.800 + How long does it take if you look at the two fast AI courses, + +1:17:56.800 --> 1:18:00.360 + how long does it take to get from 0.0 to completing + +1:18:00.360 --> 1:18:02.360 + both courses? + +1:18:02.360 --> 1:18:04.800 + It varies a lot. + +1:18:04.800 --> 1:18:12.360 + Somewhere between two months and two years, generally. + +1:18:12.360 --> 1:18:15.360 + So for two months, how many hours a day on average? + +1:18:15.360 --> 1:18:20.360 + So like somebody who is a very competent coder + +1:18:20.360 --> 1:18:27.360 + can can do 70 hours per course and pick up. + +1:18:27.360 --> 1:18:28.360 + 70, 70. + +1:18:28.360 --> 1:18:29.360 + That's it? + +1:18:29.360 --> 1:18:30.360 + OK. + +1:18:30.360 --> 1:18:36.360 + But a lot of people I know take a year off to study fast AI + +1:18:36.360 --> 1:18:39.360 + full time and say at the end of the year, + +1:18:39.360 --> 1:18:42.360 + they feel pretty competent. + +1:18:42.360 --> 1:18:45.360 + Because generally, there's a lot of other things you do. + +1:18:45.360 --> 1:18:48.360 + Generally, they'll be entering Kaggle competitions. + +1:18:48.360 --> 1:18:51.360 + They might be reading Ian Goodfellow's book. + +1:18:51.360 --> 1:18:54.360 + They might be doing a bunch of stuff. + +1:18:54.360 --> 1:18:57.360 + And often, particularly if they are a domain expert, + +1:18:57.360 --> 1:19:01.360 + their coding skills might be a little on the pedestrian side. + +1:19:01.360 --> 1:19:04.360 + So part of it's just like doing a lot more writing. + +1:19:04.360 --> 1:19:07.360 + What do you find is the bottleneck for people usually, + +1:19:07.360 --> 1:19:11.360 + except getting started and setting stuff up? + +1:19:11.360 --> 1:19:13.360 + I would say coding. + +1:19:13.360 --> 1:19:17.360 + The people who are strong coders pick it up the best. + +1:19:17.360 --> 1:19:21.360 + Although another bottleneck is people who have a lot of + +1:19:21.360 --> 1:19:27.360 + experience of classic statistics can really struggle + +1:19:27.360 --> 1:19:30.360 + because the intuition is so the opposite of what they're used to. + +1:19:30.360 --> 1:19:33.360 + They're very used to trying to reduce the number of parameters + +1:19:33.360 --> 1:19:38.360 + in their model and looking at individual coefficients + +1:19:38.360 --> 1:19:39.360 + and stuff like that. + +1:19:39.360 --> 1:19:42.360 + So I find people who have a lot of coding background + +1:19:42.360 --> 1:19:45.360 + and know nothing about statistics are generally + +1:19:45.360 --> 1:19:48.360 + going to be the best stuff. + +1:19:48.360 --> 1:19:51.360 + So you taught several courses on deep learning + +1:19:51.360 --> 1:19:54.360 + and as Feynman says, the best way to understand something + +1:19:54.360 --> 1:19:55.360 + is to teach it. + +1:19:55.360 --> 1:19:58.360 + What have you learned about deep learning from teaching it? + +1:19:58.360 --> 1:20:00.360 + A lot. + +1:20:00.360 --> 1:20:03.360 + It's a key reason for me to teach the courses. + +1:20:03.360 --> 1:20:06.360 + Obviously, it's going to be necessary to achieve our goal + +1:20:06.360 --> 1:20:09.360 + of getting domain experts to be familiar with deep learning, + +1:20:09.360 --> 1:20:12.360 + but it was also necessary for me to achieve my goal + +1:20:12.360 --> 1:20:16.360 + of being really familiar with deep learning. + +1:20:16.360 --> 1:20:24.360 + I mean, to see so many domain experts from so many different + +1:20:24.360 --> 1:20:28.360 + backgrounds, it's definitely, I wouldn't say taught me, + +1:20:28.360 --> 1:20:31.360 + but convinced me something that I liked to believe was true, + +1:20:31.360 --> 1:20:34.360 + which was anyone can do it. + +1:20:34.360 --> 1:20:37.360 + So there's a lot of kind of snobbishness out there about + +1:20:37.360 --> 1:20:39.360 + only certain people can learn to code, + +1:20:39.360 --> 1:20:42.360 + only certain people are going to be smart enough to do AI. + +1:20:42.360 --> 1:20:44.360 + That's definitely bullshit. + +1:20:44.360 --> 1:20:48.360 + I've seen so many people from so many different backgrounds + +1:20:48.360 --> 1:20:52.360 + get state of the art results in their domain areas now. + +1:20:52.360 --> 1:20:56.360 + It's definitely taught me that the key differentiator + +1:20:56.360 --> 1:21:00.360 + between people that succeed and people that fail is tenacity. + +1:21:00.360 --> 1:21:03.360 + That seems to be basically the only thing that matters. + +1:21:03.360 --> 1:21:07.360 + A lot of people give up. + +1:21:07.360 --> 1:21:13.360 + But if the ones who don't give up pretty much everybody succeeds, + +1:21:13.360 --> 1:21:17.360 + even if at first I'm just kind of thinking, + +1:21:17.360 --> 1:21:20.360 + wow, they really aren't quite getting it yet, are they? + +1:21:20.360 --> 1:21:24.360 + But eventually people get it and they succeed. + +1:21:24.360 --> 1:21:27.360 + So I think that's been, I think they're both things I liked + +1:21:27.360 --> 1:21:29.360 + to believe was true, but I don't feel like I really had + +1:21:29.360 --> 1:21:31.360 + strong evidence for them to be true, + +1:21:31.360 --> 1:21:34.360 + but now I can see I've seen it again and again. + +1:21:34.360 --> 1:21:39.360 + So what advice do you have for someone + +1:21:39.360 --> 1:21:42.360 + who wants to get started in deep learning? + +1:21:42.360 --> 1:21:44.360 + Train lots of models. + +1:21:44.360 --> 1:21:47.360 + That's how you learn it. + +1:21:47.360 --> 1:21:51.360 + So I think, it's not just me. + +1:21:51.360 --> 1:21:53.360 + I think our course is very good, + +1:21:53.360 --> 1:21:55.360 + but also lots of people independently have said it's very good. + +1:21:55.360 --> 1:21:58.360 + It recently won the CogEx Award for AI courses, + +1:21:58.360 --> 1:22:00.360 + it's being the best in the world. + +1:22:00.360 --> 1:22:02.360 + I'd say come to our course, course.fast.ai. + +1:22:02.360 --> 1:22:05.360 + And the thing I keep on harping on in my lessons is + +1:22:05.360 --> 1:22:08.360 + train models, print out the inputs to the models, + +1:22:08.360 --> 1:22:10.360 + print out to the outputs to the models, + +1:22:10.360 --> 1:22:14.360 + like study, you know, change the inputs a bit, + +1:22:14.360 --> 1:22:16.360 + look at how the outputs vary, + +1:22:16.360 --> 1:22:22.360 + just run lots of experiments to get an intuitive understanding + +1:22:22.360 --> 1:22:24.360 + of what's going on. + +1:22:24.360 --> 1:22:28.360 + To get hooked, do you think, you mentioned training, + +1:22:28.360 --> 1:22:32.360 + do you think just running the models inference? + +1:22:32.360 --> 1:22:35.360 + If we talk about getting started. + +1:22:35.360 --> 1:22:37.360 + No, you've got to fine tune the models. + +1:22:37.360 --> 1:22:39.360 + So that's the critical thing, + +1:22:39.360 --> 1:22:43.360 + because at that point, you now have a model that's in your domain area. + +1:22:43.360 --> 1:22:46.360 + So there's no point running somebody else's model, + +1:22:46.360 --> 1:22:48.360 + because it's not your model. + +1:22:48.360 --> 1:22:50.360 + So it only takes five minutes to fine tune a model + +1:22:50.360 --> 1:22:52.360 + for the data you care about. + +1:22:52.360 --> 1:22:54.360 + And in lesson two of the course, + +1:22:54.360 --> 1:22:56.360 + we teach you how to create your own dataset from scratch + +1:22:56.360 --> 1:22:58.360 + by scripting Google image search. + +1:22:58.360 --> 1:23:02.360 + And we show you how to actually create a web application running online. + +1:23:02.360 --> 1:23:05.360 + So I create one in the course that differentiates + +1:23:05.360 --> 1:23:08.360 + between a teddy bear, a grizzly bear, and a brown bear. + +1:23:08.360 --> 1:23:10.360 + And it does it with basically 100% accuracy. + +1:23:10.360 --> 1:23:13.360 + It took me about four minutes to scrape the images + +1:23:13.360 --> 1:23:15.360 + from Google search in the script. + +1:23:15.360 --> 1:23:18.360 + There's a little graphical widgets we have in the notebook + +1:23:18.360 --> 1:23:21.360 + that help you clean up the dataset. + +1:23:21.360 --> 1:23:24.360 + There's other widgets that help you study the results + +1:23:24.360 --> 1:23:26.360 + and see where the errors are happening. + +1:23:26.360 --> 1:23:29.360 + And so now we've got over a thousand replies + +1:23:29.360 --> 1:23:32.360 + in our Share Your Work Here thread of students saying, + +1:23:32.360 --> 1:23:34.360 + here's the thing I built. + +1:23:34.360 --> 1:23:36.360 + And so there's people who, like, + +1:23:36.360 --> 1:23:38.360 + and a lot of them are state of the art. + +1:23:38.360 --> 1:23:40.360 + Like somebody said, oh, I tried looking at Dev and Gary characters + +1:23:40.360 --> 1:23:42.360 + and I couldn't believe it. + +1:23:42.360 --> 1:23:44.360 + The thing that came out was more accurate + +1:23:44.360 --> 1:23:46.360 + than the best academic paper after lesson one. + +1:23:46.360 --> 1:23:48.360 + And then there's others which are just more kind of fun, + +1:23:48.360 --> 1:23:53.360 + like somebody who's doing Trinidad and Tobago hummingbirds. + +1:23:53.360 --> 1:23:55.360 + So that's kind of their national bird. + +1:23:55.360 --> 1:23:57.360 + And Susie's got something that can now classify Trinidad + +1:23:57.360 --> 1:23:59.360 + and Tobago hummingbirds. + +1:23:59.360 --> 1:24:02.360 + So yeah, train models, fine tune models with your dataset + +1:24:02.360 --> 1:24:05.360 + and then study their inputs and outputs. + +1:24:05.360 --> 1:24:07.360 + How much is Fast AI courses? + +1:24:07.360 --> 1:24:09.360 + Free. + +1:24:09.360 --> 1:24:11.360 + Everything we do is free. + +1:24:11.360 --> 1:24:13.360 + We have no revenue sources of any kind. + +1:24:13.360 --> 1:24:15.360 + It's just a service to the community. + +1:24:15.360 --> 1:24:17.360 + You're a saint. + +1:24:17.360 --> 1:24:20.360 + Okay, once a person understands the basics, + +1:24:20.360 --> 1:24:22.360 + trains a bunch of models, + +1:24:22.360 --> 1:24:25.360 + if we look at the scale of years, + +1:24:25.360 --> 1:24:27.360 + what advice do you have for someone wanting + +1:24:27.360 --> 1:24:30.360 + to eventually become an expert? + +1:24:30.360 --> 1:24:32.360 + Train lots of models. + +1:24:32.360 --> 1:24:35.360 + Specifically, train lots of models in your domain area. + +1:24:35.360 --> 1:24:37.360 + So an expert, what, right? + +1:24:37.360 --> 1:24:40.360 + We don't need more expert, like, + +1:24:40.360 --> 1:24:45.360 + create slightly evolutionary research in areas + +1:24:45.360 --> 1:24:47.360 + that everybody's studying. + +1:24:47.360 --> 1:24:50.360 + We need experts at using deep learning + +1:24:50.360 --> 1:24:52.360 + to diagnose malaria. + +1:24:52.360 --> 1:24:55.360 + Well, we need experts at using deep learning + +1:24:55.360 --> 1:25:00.360 + to analyze language to study media bias. + +1:25:00.360 --> 1:25:08.360 + So we need experts in analyzing fisheries + +1:25:08.360 --> 1:25:11.360 + to identify problem areas and the ocean. + +1:25:11.360 --> 1:25:13.360 + That's what we need. + +1:25:13.360 --> 1:25:17.360 + So become the expert in your passion area. + +1:25:17.360 --> 1:25:21.360 + And this is a tool which you can use for just about anything, + +1:25:21.360 --> 1:25:24.360 + and you'll be able to do that thing better than other people, + +1:25:24.360 --> 1:25:26.360 + particularly by combining it with your passion + +1:25:26.360 --> 1:25:27.360 + and domain expertise. + +1:25:27.360 --> 1:25:28.360 + So that's really interesting. + +1:25:28.360 --> 1:25:30.360 + Even if you do want to innovate on transfer learning + +1:25:30.360 --> 1:25:32.360 + or active learning, + +1:25:32.360 --> 1:25:34.360 + your thought is, I mean, + +1:25:34.360 --> 1:25:38.360 + what I certainly share is you also need to find + +1:25:38.360 --> 1:25:41.360 + a domain or data set that you actually really care for. + +1:25:41.360 --> 1:25:42.360 + Right. + +1:25:42.360 --> 1:25:45.360 + If you're not working on a real problem that you understand, + +1:25:45.360 --> 1:25:47.360 + how do you know if you're doing it any good? + +1:25:47.360 --> 1:25:49.360 + How do you know if your results are good? + +1:25:49.360 --> 1:25:51.360 + How do you know if you're getting bad results? + +1:25:51.360 --> 1:25:52.360 + Why are you getting bad results? + +1:25:52.360 --> 1:25:54.360 + Is it a problem with the data? + +1:25:54.360 --> 1:25:57.360 + How do you know you're doing anything useful? + +1:25:57.360 --> 1:26:00.360 + Yeah, to me, the only really interesting research is, + +1:26:00.360 --> 1:26:03.360 + not the only, but the vast majority of interesting research + +1:26:03.360 --> 1:26:06.360 + is try and solve an actual problem and solve it really well. + +1:26:06.360 --> 1:26:10.360 + So both understanding sufficient tools on the deep learning side + +1:26:10.360 --> 1:26:14.360 + and becoming a domain expert in a particular domain + +1:26:14.360 --> 1:26:18.360 + are really things within reach for anybody. + +1:26:18.360 --> 1:26:19.360 + Yeah. + +1:26:19.360 --> 1:26:23.360 + To me, I would compare it to studying self driving cars, + +1:26:23.360 --> 1:26:26.360 + having never looked at a car or been in a car + +1:26:26.360 --> 1:26:29.360 + or turned a car on, which is like the way it is + +1:26:29.360 --> 1:26:30.360 + for a lot of people. + +1:26:30.360 --> 1:26:33.360 + They'll study some academic data set + +1:26:33.360 --> 1:26:36.360 + where they literally have no idea about that. + +1:26:36.360 --> 1:26:37.360 + By the way, I'm not sure how familiar + +1:26:37.360 --> 1:26:39.360 + you are with autonomous vehicles, + +1:26:39.360 --> 1:26:42.360 + but that is literally, you describe a large percentage + +1:26:42.360 --> 1:26:45.360 + of robotics folks working in self driving cars, + +1:26:45.360 --> 1:26:48.360 + as they actually haven't considered driving. + +1:26:48.360 --> 1:26:50.360 + They haven't actually looked at what driving looks like. + +1:26:50.360 --> 1:26:51.360 + They haven't driven. + +1:26:51.360 --> 1:26:52.360 + And it applies. + +1:26:52.360 --> 1:26:54.360 + It's a problem because you know when you've actually driven, + +1:26:54.360 --> 1:26:57.360 + these are the things that happened to me when I was driving. + +1:26:57.360 --> 1:26:59.360 + There's nothing that beats the real world examples + +1:26:59.360 --> 1:27:02.360 + or just experiencing them. + +1:27:02.360 --> 1:27:04.360 + You've created many successful startups. + +1:27:04.360 --> 1:27:08.360 + What does it take to create a successful startup? + +1:27:08.360 --> 1:27:12.360 + Same thing as becoming successful deep learning practitioner, + +1:27:12.360 --> 1:27:14.360 + which is not giving up. + +1:27:14.360 --> 1:27:22.360 + So you can run out of money or run out of time + +1:27:22.360 --> 1:27:24.360 + or run out of something, you know, + +1:27:24.360 --> 1:27:27.360 + but if you keep costs super low + +1:27:27.360 --> 1:27:29.360 + and try and save up some money beforehand + +1:27:29.360 --> 1:27:34.360 + so you can afford to have some time, + +1:27:34.360 --> 1:27:37.360 + then just sticking with it is one important thing. + +1:27:37.360 --> 1:27:42.360 + Doing something you understand and care about is important. + +1:27:42.360 --> 1:27:44.360 + By something, I don't mean... + +1:27:44.360 --> 1:27:46.360 + The biggest problem I see with deep learning people + +1:27:46.360 --> 1:27:49.360 + is they do a PhD in deep learning + +1:27:49.360 --> 1:27:52.360 + and then they try and commercialize their PhD. + +1:27:52.360 --> 1:27:53.360 + It does a waste of time + +1:27:53.360 --> 1:27:55.360 + because that doesn't solve an actual problem. + +1:27:55.360 --> 1:27:57.360 + You picked your PhD topic + +1:27:57.360 --> 1:28:00.360 + because it was an interesting kind of engineering + +1:28:00.360 --> 1:28:02.360 + or math or research exercise. + +1:28:02.360 --> 1:28:06.360 + But yeah, if you've actually spent time as a recruiter + +1:28:06.360 --> 1:28:10.360 + and you know that most of your time was spent sifting through resumes + +1:28:10.360 --> 1:28:12.360 + and you know that most of the time + +1:28:12.360 --> 1:28:14.360 + you're just looking for certain kinds of things + +1:28:14.360 --> 1:28:19.360 + and you can try doing that with a model for a few minutes + +1:28:19.360 --> 1:28:21.360 + and see whether that's something which a model + +1:28:21.360 --> 1:28:23.360 + seems to be able to do as well as you could, + +1:28:23.360 --> 1:28:27.360 + then you're on the right track to creating a startup. + +1:28:27.360 --> 1:28:30.360 + And then I think just being... + +1:28:30.360 --> 1:28:34.360 + Just be pragmatic and... + +1:28:34.360 --> 1:28:36.360 + try and stay away from venture capital money + +1:28:36.360 --> 1:28:38.360 + as long as possible, preferably forever. + +1:28:38.360 --> 1:28:42.360 + So yeah, on that point, do you... + +1:28:42.360 --> 1:28:43.360 + venture capital... + +1:28:43.360 --> 1:28:46.360 + So were you able to successfully run startups + +1:28:46.360 --> 1:28:48.360 + with self funded for quite a while? + +1:28:48.360 --> 1:28:50.360 + Yeah, so my first two were self funded + +1:28:50.360 --> 1:28:52.360 + and that was the right way to do it. + +1:28:52.360 --> 1:28:53.360 + Is that scary? + +1:28:53.360 --> 1:28:55.360 + No. + +1:28:55.360 --> 1:28:57.360 + VCs startups are much more scary + +1:28:57.360 --> 1:29:00.360 + because you have these people on your back + +1:29:00.360 --> 1:29:01.360 + who do this all the time + +1:29:01.360 --> 1:29:03.360 + and who have done it for years + +1:29:03.360 --> 1:29:05.360 + telling you grow, grow, grow, grow. + +1:29:05.360 --> 1:29:07.360 + And they don't care if you fail. + +1:29:07.360 --> 1:29:09.360 + They only care if you don't grow fast enough. + +1:29:09.360 --> 1:29:10.360 + So that's scary. + +1:29:10.360 --> 1:29:13.360 + We're else doing the ones myself + +1:29:13.360 --> 1:29:17.360 + with partners who were friends. + +1:29:17.360 --> 1:29:20.360 + It's nice because we just went along + +1:29:20.360 --> 1:29:22.360 + at a pace that made sense + +1:29:22.360 --> 1:29:24.360 + and we were able to build it to something + +1:29:24.360 --> 1:29:27.360 + which was big enough that we never had to work again + +1:29:27.360 --> 1:29:29.360 + but was not big enough that any VC + +1:29:29.360 --> 1:29:31.360 + would think it was impressive + +1:29:31.360 --> 1:29:35.360 + and that was enough for us to be excited. + +1:29:35.360 --> 1:29:38.360 + So I thought that's a much better way + +1:29:38.360 --> 1:29:40.360 + to do things for most people. + +1:29:40.360 --> 1:29:42.360 + And generally speaking now for yourself + +1:29:42.360 --> 1:29:44.360 + but how do you make money during that process? + +1:29:44.360 --> 1:29:47.360 + Do you cut into savings? + +1:29:47.360 --> 1:29:49.360 + So yeah, so I started Fast Mail + +1:29:49.360 --> 1:29:51.360 + and Optimal Decisions at the same time + +1:29:51.360 --> 1:29:54.360 + in 1999 with two different friends. + +1:29:54.360 --> 1:29:59.360 + And for Fast Mail, + +1:29:59.360 --> 1:30:03.360 + I guess I spent $70 a month on the server. + +1:30:03.360 --> 1:30:06.360 + And when the server ran out of space + +1:30:06.360 --> 1:30:09.360 + I put a payments button on the front page + +1:30:09.360 --> 1:30:11.360 + and said if you want more than 10 meg of space + +1:30:11.360 --> 1:30:15.360 + you have to pay $10 a year. + +1:30:15.360 --> 1:30:18.360 + So run low like I keep your cost down. + +1:30:18.360 --> 1:30:19.360 + Yeah, so I kept my cost down + +1:30:19.360 --> 1:30:22.360 + and once I needed to spend more money + +1:30:22.360 --> 1:30:25.360 + I asked people to spend the money for me + +1:30:25.360 --> 1:30:29.360 + and that was that basically from then on. + +1:30:29.360 --> 1:30:34.360 + We were making money and I was profitable from then. + +1:30:34.360 --> 1:30:37.360 + For Optimal Decisions it was a bit harder + +1:30:37.360 --> 1:30:40.360 + because we were trying to sell something + +1:30:40.360 --> 1:30:42.360 + that was more like a $1 million sale + +1:30:42.360 --> 1:30:46.360 + but what we did was we would sell scoping projects + +1:30:46.360 --> 1:30:50.360 + so kind of like prototypy projects + +1:30:50.360 --> 1:30:51.360 + but rather than doing it for free + +1:30:51.360 --> 1:30:54.360 + we would sell them $50,000 to $100,000. + +1:30:54.360 --> 1:30:57.360 + So again we were covering our costs + +1:30:57.360 --> 1:30:58.360 + and also making the client feel like + +1:30:58.360 --> 1:31:00.360 + we were doing something valuable. + +1:31:00.360 --> 1:31:06.360 + So in both cases we were profitable from six months in. + +1:31:06.360 --> 1:31:08.360 + Nevertheless it's scary. + +1:31:08.360 --> 1:31:10.360 + I mean, yeah, sure. + +1:31:10.360 --> 1:31:13.360 + I mean it's scary before you jump in + +1:31:13.360 --> 1:31:18.360 + and I guess I was comparing it to the scaredyness of VC. + +1:31:18.360 --> 1:31:20.360 + I felt like with VC stuff it was more scary. + +1:31:20.360 --> 1:31:24.360 + Much more in somebody else's hands. + +1:31:24.360 --> 1:31:26.360 + Will they fund you or not? + +1:31:26.360 --> 1:31:28.360 + What do they think of what you're doing? + +1:31:28.360 --> 1:31:30.360 + I also found it very difficult with VC's back startups + +1:31:30.360 --> 1:31:33.360 + to actually do the thing which I thought was important + +1:31:33.360 --> 1:31:35.360 + for the company rather than doing the thing + +1:31:35.360 --> 1:31:38.360 + which I thought would make the VC happy. + +1:31:38.360 --> 1:31:40.360 + Now, VC's always tell you not to do the thing + +1:31:40.360 --> 1:31:41.360 + that makes them happy + +1:31:41.360 --> 1:31:43.360 + but then if you don't do the thing that makes them happy + +1:31:43.360 --> 1:31:45.360 + they get sad. + +1:31:45.360 --> 1:31:48.360 + And do you think optimizing for the whatever they call it + +1:31:48.360 --> 1:31:52.360 + the exit is a good thing to optimize for? + +1:31:52.360 --> 1:31:54.360 + I mean it can be but not at the VC level + +1:31:54.360 --> 1:31:59.360 + because the VC exit needs to be, you know, a thousand X. + +1:31:59.360 --> 1:32:02.360 + So where else the lifestyle exit + +1:32:02.360 --> 1:32:04.360 + if you can sell something for $10 million + +1:32:04.360 --> 1:32:06.360 + then you've made it, right? + +1:32:06.360 --> 1:32:08.360 + So it depends. + +1:32:08.360 --> 1:32:10.360 + If you want to build something that's going to, + +1:32:10.360 --> 1:32:13.360 + you're kind of happy to do forever then fine. + +1:32:13.360 --> 1:32:16.360 + If you want to build something you want to sell + +1:32:16.360 --> 1:32:18.360 + then three years time that's fine too. + +1:32:18.360 --> 1:32:21.360 + I mean they're both perfectly good outcomes. + +1:32:21.360 --> 1:32:24.360 + So you're learning Swift now? + +1:32:24.360 --> 1:32:26.360 + In a way, I mean you already. + +1:32:26.360 --> 1:32:31.360 + And I read that you use at least in some cases + +1:32:31.360 --> 1:32:34.360 + space repetition as a mechanism for learning new things. + +1:32:34.360 --> 1:32:38.360 + I use Anki quite a lot myself. + +1:32:38.360 --> 1:32:41.360 + I actually don't never talk to anybody about it. + +1:32:41.360 --> 1:32:44.360 + Don't know how many people do it + +1:32:44.360 --> 1:32:46.360 + and it works incredibly well for me. + +1:32:46.360 --> 1:32:48.360 + Can you talk to your experience? + +1:32:48.360 --> 1:32:52.360 + Like how did you, what do you, first of all, okay, + +1:32:52.360 --> 1:32:53.360 + let's back it up. + +1:32:53.360 --> 1:32:55.360 + What is space repetition? + +1:32:55.360 --> 1:33:00.360 + So space repetition is an idea created + +1:33:00.360 --> 1:33:03.360 + by a psychologist named Ebbinghaus, + +1:33:03.360 --> 1:33:06.360 + I don't know, must be a couple hundred years ago + +1:33:06.360 --> 1:33:08.360 + or something 150 years ago. + +1:33:08.360 --> 1:33:11.360 + He did something which sounds pretty damn tedious. + +1:33:11.360 --> 1:33:16.360 + He found random sequences of letters on cards + +1:33:16.360 --> 1:33:21.360 + and tested how well he would remember those random sequences + +1:33:21.360 --> 1:33:23.360 + a day later, a week later, whatever. + +1:33:23.360 --> 1:33:26.360 + He discovered that there was this kind of a curve + +1:33:26.360 --> 1:33:29.360 + where his probability of remembering one of them + +1:33:29.360 --> 1:33:31.360 + would be dramatically smaller the next day + +1:33:31.360 --> 1:33:32.360 + and then a little bit smaller the next day + +1:33:32.360 --> 1:33:34.360 + and a little bit smaller the next day. + +1:33:34.360 --> 1:33:37.360 + What he discovered is that if he revised those cards + +1:33:37.360 --> 1:33:42.360 + a day, the probabilities would decrease at a smaller rate + +1:33:42.360 --> 1:33:44.360 + and then if he revised them again a week later, + +1:33:44.360 --> 1:33:46.360 + they would decrease at a smaller rate again. + +1:33:46.360 --> 1:33:51.360 + And so he basically figured out a roughly optimal equation + +1:33:51.360 --> 1:33:56.360 + for when you should revise something you want to remember. + +1:33:56.360 --> 1:34:00.360 + So space repetition learning is using this simple algorithm, + +1:34:00.360 --> 1:34:03.360 + just something like revise something after a day + +1:34:03.360 --> 1:34:06.360 + and then three days and then a week and then three weeks + +1:34:06.360 --> 1:34:07.360 + and so forth. + +1:34:07.360 --> 1:34:10.360 + And so if you use a program like Anki, as you know, + +1:34:10.360 --> 1:34:12.360 + it will just do that for you. + +1:34:12.360 --> 1:34:14.360 + And it will say, did you remember this? + +1:34:14.360 --> 1:34:18.360 + And if you say no, it will reschedule it back to be + +1:34:18.360 --> 1:34:22.360 + appear again like 10 times faster than it otherwise would have. + +1:34:22.360 --> 1:34:27.360 + It's a kind of a way of being guaranteed to learn something + +1:34:27.360 --> 1:34:30.360 + because by definition, if you're not learning it, + +1:34:30.360 --> 1:34:33.360 + it will be rescheduled to be revised more quickly. + +1:34:33.360 --> 1:34:37.360 + Unfortunately though, it doesn't let you fool yourself. + +1:34:37.360 --> 1:34:42.360 + If you're not learning something, you know your revisions + +1:34:42.360 --> 1:34:44.360 + will just get more and more. + +1:34:44.360 --> 1:34:48.360 + So you have to find ways to learn things productively + +1:34:48.360 --> 1:34:50.360 + and effectively treat your brain well. + +1:34:50.360 --> 1:34:57.360 + So using mnemonics and stories and context and stuff like that. + +1:34:57.360 --> 1:34:59.360 + So yeah, it's a super great technique. + +1:34:59.360 --> 1:35:01.360 + It's like learning how to learn is something + +1:35:01.360 --> 1:35:05.360 + which everybody should learn before they actually learn anything. + +1:35:05.360 --> 1:35:07.360 + But almost nobody does. + +1:35:07.360 --> 1:35:10.360 + Yes, so what have you, so it certainly works well + +1:35:10.360 --> 1:35:14.360 + for learning new languages, for, I mean, for learning, + +1:35:14.360 --> 1:35:16.360 + like small projects almost. + +1:35:16.360 --> 1:35:19.360 + But do you, you know, I started using it for, + +1:35:19.360 --> 1:35:22.360 + I forget who wrote a blog post about this inspired me. + +1:35:22.360 --> 1:35:25.360 + It might have been you, I'm not sure. + +1:35:25.360 --> 1:35:28.360 + I started when I read papers. + +1:35:28.360 --> 1:35:31.360 + I'll, concepts and ideas, I'll put them. + +1:35:31.360 --> 1:35:32.360 + Was it Michael Nielsen? + +1:35:32.360 --> 1:35:33.360 + It was Michael Nielsen. + +1:35:33.360 --> 1:35:34.360 + Yeah, it was Michael Nielsen. + +1:35:34.360 --> 1:35:36.360 + Michael started doing this recently + +1:35:36.360 --> 1:35:39.360 + and has been writing about it. + +1:35:39.360 --> 1:35:44.360 + I, so the kind of today's ebbing house is a guy called Peter Wozniak + +1:35:44.360 --> 1:35:47.360 + who developed a system called Super Memo. + +1:35:47.360 --> 1:35:51.360 + And he's been basically trying to become like + +1:35:51.360 --> 1:35:55.360 + the world's greatest renaissance man over the last few decades. + +1:35:55.360 --> 1:36:00.360 + He's basically lived his life with space repetition learning + +1:36:00.360 --> 1:36:03.360 + for everything. + +1:36:03.360 --> 1:36:07.360 + I, and sort of like Michael's only very recently got into this, + +1:36:07.360 --> 1:36:09.360 + but he started really getting excited about doing it + +1:36:09.360 --> 1:36:10.360 + for a lot of different things. + +1:36:10.360 --> 1:36:14.360 + For me personally, I actually don't use it + +1:36:14.360 --> 1:36:16.360 + for anything except Chinese. + +1:36:16.360 --> 1:36:21.360 + And the reason for that is that Chinese is specifically a thing. + +1:36:21.360 --> 1:36:26.360 + I made a conscious decision that I want to continue to remember + +1:36:26.360 --> 1:36:29.360 + even if I don't get much of a chance to exercise it + +1:36:29.360 --> 1:36:33.360 + because like I'm not often in China, so I don't. + +1:36:33.360 --> 1:36:37.360 + Or else something like programming languages or papers, + +1:36:37.360 --> 1:36:39.360 + they have a very different approach, + +1:36:39.360 --> 1:36:42.360 + which is I try not to learn anything from them, + +1:36:42.360 --> 1:36:46.360 + but instead I try to identify the important concepts + +1:36:46.360 --> 1:36:48.360 + and like actually ingest them. + +1:36:48.360 --> 1:36:53.360 + So like really understand that concept deeply + +1:36:53.360 --> 1:36:54.360 + and study it carefully. + +1:36:54.360 --> 1:36:56.360 + Well, decide if it really is important. + +1:36:56.360 --> 1:37:00.360 + If it is like incorporate it into our library, + +1:37:00.360 --> 1:37:03.360 + you know, incorporate it into how I do things + +1:37:03.360 --> 1:37:06.360 + or decide it's not worth it. + +1:37:06.360 --> 1:37:12.360 + So I find I then remember the things that I care about + +1:37:12.360 --> 1:37:15.360 + because I'm using it all the time. + +1:37:15.360 --> 1:37:19.360 + So for the last 25 years, + +1:37:19.360 --> 1:37:23.360 + I've committed to spending at least half of every day + +1:37:23.360 --> 1:37:25.360 + learning or practicing something new, + +1:37:25.360 --> 1:37:28.360 + which is all my colleagues have always hated + +1:37:28.360 --> 1:37:30.360 + because it always looks like I'm not working on + +1:37:30.360 --> 1:37:31.360 + what I'm meant to be working on, + +1:37:31.360 --> 1:37:34.360 + but that always means I do everything faster + +1:37:34.360 --> 1:37:36.360 + because I've been practicing a lot of stuff. + +1:37:36.360 --> 1:37:39.360 + So I kind of give myself a lot of opportunity + +1:37:39.360 --> 1:37:41.360 + to practice new things. + +1:37:41.360 --> 1:37:47.360 + And so I find now I don't often kind of find myself + +1:37:47.360 --> 1:37:50.360 + wishing I could remember something + +1:37:50.360 --> 1:37:51.360 + because if it's something that's useful, + +1:37:51.360 --> 1:37:53.360 + then I've been using it a lot. + +1:37:53.360 --> 1:37:55.360 + It's easy enough to look it up on Google. + +1:37:55.360 --> 1:37:59.360 + But speaking Chinese, you can't look it up on Google. + +1:37:59.360 --> 1:38:01.360 + Do you have advice for people learning new things? + +1:38:01.360 --> 1:38:04.360 + What have you learned as a process? + +1:38:04.360 --> 1:38:07.360 + I mean, it all starts just making the hours + +1:38:07.360 --> 1:38:08.360 + and the day available. + +1:38:08.360 --> 1:38:10.360 + Yeah, you've got to stick with it, + +1:38:10.360 --> 1:38:12.360 + which is, again, the number one thing + +1:38:12.360 --> 1:38:14.360 + that 99% of people don't do. + +1:38:14.360 --> 1:38:16.360 + So the people I started learning Chinese with, + +1:38:16.360 --> 1:38:18.360 + none of them were still doing it 12 months later. + +1:38:18.360 --> 1:38:20.360 + I'm still doing it 10 years later. + +1:38:20.360 --> 1:38:22.360 + I tried to stay in touch with them, + +1:38:22.360 --> 1:38:24.360 + but they just, no one did it. + +1:38:24.360 --> 1:38:26.360 + For something like Chinese, + +1:38:26.360 --> 1:38:28.360 + like study how human learning works. + +1:38:28.360 --> 1:38:31.360 + So every one of my Chinese flashcards + +1:38:31.360 --> 1:38:33.360 + is associated with a story, + +1:38:33.360 --> 1:38:36.360 + and that story is specifically designed to be memorable. + +1:38:36.360 --> 1:38:38.360 + And we find things memorable, + +1:38:38.360 --> 1:38:41.360 + funny or disgusting or sexy + +1:38:41.360 --> 1:38:44.360 + or related to people that we know or care about. + +1:38:44.360 --> 1:38:47.360 + So I try to make sure all the stories that are in my head + +1:38:47.360 --> 1:38:50.360 + have those characteristics. + +1:38:50.360 --> 1:38:52.360 + Yeah, so you have to, you know, + +1:38:52.360 --> 1:38:55.360 + you won't remember things well if they don't have some context. + +1:38:55.360 --> 1:38:57.360 + And yeah, you won't remember them well + +1:38:57.360 --> 1:39:00.360 + if you don't regularly practice them, + +1:39:00.360 --> 1:39:02.360 + whether it be just part of your day to day life + +1:39:02.360 --> 1:39:05.360 + for the Chinese and me flashcards. + +1:39:05.360 --> 1:39:09.360 + I mean, the other thing is, let yourself fail sometimes. + +1:39:09.360 --> 1:39:11.360 + So like, I've had various medical problems + +1:39:11.360 --> 1:39:13.360 + over the last few years, + +1:39:13.360 --> 1:39:16.360 + and basically my flashcards just stopped + +1:39:16.360 --> 1:39:18.360 + for about three years. + +1:39:18.360 --> 1:39:21.360 + And then there've been other times I've stopped + +1:39:21.360 --> 1:39:24.360 + for a few months, and it's so hard because you get back to it, + +1:39:24.360 --> 1:39:27.360 + and it's like, you have 18,000 cards due. + +1:39:27.360 --> 1:39:30.360 + It's like, and so you just have to go, + +1:39:30.360 --> 1:39:33.360 + all right, well, I can either stop and give up everything + +1:39:33.360 --> 1:39:36.360 + or just decide to do this every day for the next two years + +1:39:36.360 --> 1:39:38.360 + until I get back to it. + +1:39:38.360 --> 1:39:41.360 + The amazing thing has been that even after three years, + +1:39:41.360 --> 1:39:45.360 + I, you know, the Chinese were still in there. + +1:39:45.360 --> 1:39:47.360 + Like, it was so much faster to relearn + +1:39:47.360 --> 1:39:49.360 + than it was to mine the first time. + +1:39:49.360 --> 1:39:51.360 + Yeah, absolutely. + +1:39:51.360 --> 1:39:52.360 + It's in there. + +1:39:52.360 --> 1:39:55.360 + I have the same with guitar, with music and so on. + +1:39:55.360 --> 1:39:58.360 + It's sad because work sometimes takes away + +1:39:58.360 --> 1:40:00.360 + and then you won't play for a year. + +1:40:00.360 --> 1:40:03.360 + But really, if you then just get back to it every day, + +1:40:03.360 --> 1:40:05.360 + you're right there again. + +1:40:05.360 --> 1:40:08.360 + What do you think is the next big breakthrough + +1:40:08.360 --> 1:40:09.360 + in artificial intelligence? + +1:40:09.360 --> 1:40:12.360 + What are your hopes in deep learning or beyond + +1:40:12.360 --> 1:40:14.360 + that people should be working on, + +1:40:14.360 --> 1:40:16.360 + or you hope there'll be breakthroughs? + +1:40:16.360 --> 1:40:18.360 + I don't think it's possible to predict. + +1:40:18.360 --> 1:40:20.360 + I think what we already have + +1:40:20.360 --> 1:40:23.360 + is an incredibly powerful platform + +1:40:23.360 --> 1:40:26.360 + to solve lots of societally important problems + +1:40:26.360 --> 1:40:28.360 + that are currently unsolved. + +1:40:28.360 --> 1:40:30.360 + I just hope that people will, lots of people + +1:40:30.360 --> 1:40:33.360 + will learn this toolkit and try to use it. + +1:40:33.360 --> 1:40:36.360 + I don't think we need a lot of new technological breakthroughs + +1:40:36.360 --> 1:40:39.360 + to do a lot of great work right now. + +1:40:39.360 --> 1:40:42.360 + And when do you think we're going to create + +1:40:42.360 --> 1:40:44.360 + a human level intelligence system? + +1:40:44.360 --> 1:40:45.360 + Do you think? + +1:40:45.360 --> 1:40:46.360 + I don't know. + +1:40:46.360 --> 1:40:47.360 + How hard is it? + +1:40:47.360 --> 1:40:48.360 + How far away are we? + +1:40:48.360 --> 1:40:49.360 + I don't know. + +1:40:49.360 --> 1:40:50.360 + I have no way to know. + +1:40:50.360 --> 1:40:51.360 + I don't know. + +1:40:51.360 --> 1:40:53.360 + Like, I don't know why people make predictions about this + +1:40:53.360 --> 1:40:57.360 + because there's no data and nothing to go on. + +1:40:57.360 --> 1:40:59.360 + And it's just like, + +1:40:59.360 --> 1:41:03.360 + there's so many societally important problems + +1:41:03.360 --> 1:41:04.360 + to solve right now, + +1:41:04.360 --> 1:41:08.360 + I just don't find it a really interesting question + +1:41:08.360 --> 1:41:09.360 + to even answer. + +1:41:09.360 --> 1:41:12.360 + So in terms of societally important problems, + +1:41:12.360 --> 1:41:15.360 + what's the problem that is within reach? + +1:41:15.360 --> 1:41:17.360 + Well, I mean, for example, + +1:41:17.360 --> 1:41:19.360 + there are problems that AI creates, right? + +1:41:19.360 --> 1:41:21.360 + So more specifically, + +1:41:22.360 --> 1:41:26.360 + labor force displacement is going to be huge + +1:41:26.360 --> 1:41:28.360 + and people keep making this + +1:41:28.360 --> 1:41:31.360 + frivolous econometric argument of being like, + +1:41:31.360 --> 1:41:33.360 + oh, there's been other things that aren't AI + +1:41:33.360 --> 1:41:34.360 + that have come along before + +1:41:34.360 --> 1:41:37.360 + and haven't created massive labor force displacement. + +1:41:37.360 --> 1:41:39.360 + Therefore, AI won't. + +1:41:39.360 --> 1:41:41.360 + So that's a serious concern for you? + +1:41:41.360 --> 1:41:42.360 + Oh, yeah. + +1:41:42.360 --> 1:41:43.360 + Andrew Yang is running on it. + +1:41:43.360 --> 1:41:44.360 + Yeah. + +1:41:44.360 --> 1:41:46.360 + It's desperately concerned. + +1:41:46.360 --> 1:41:52.360 + And you see already that the changing workplace + +1:41:52.360 --> 1:41:55.360 + has lived to a hollowing out of the middle class. + +1:41:55.360 --> 1:41:58.360 + You're seeing that students coming out of school today + +1:41:58.360 --> 1:42:03.360 + have a less rosy financial future ahead of them + +1:42:03.360 --> 1:42:04.360 + than the parents did, + +1:42:04.360 --> 1:42:06.360 + which has never happened in recent, + +1:42:06.360 --> 1:42:08.360 + in the last 300 years. + +1:42:08.360 --> 1:42:11.360 + We've always had progress before. + +1:42:11.360 --> 1:42:16.360 + And you see this turning into anxiety and despair + +1:42:16.360 --> 1:42:19.360 + and even violence. + +1:42:19.360 --> 1:42:21.360 + So I very much worry about that. + +1:42:21.360 --> 1:42:24.360 + You've written quite a bit about ethics, too. + +1:42:24.360 --> 1:42:27.360 + I do think that every data scientist + +1:42:27.360 --> 1:42:32.360 + working with deep learning needs to recognize + +1:42:32.360 --> 1:42:34.360 + they have an incredibly high leverage tool + +1:42:34.360 --> 1:42:36.360 + that they're using that can influence society + +1:42:36.360 --> 1:42:37.360 + in lots of ways. + +1:42:37.360 --> 1:42:38.360 + And if they're doing research, + +1:42:38.360 --> 1:42:41.360 + that research is going to be used by people + +1:42:41.360 --> 1:42:42.360 + doing this kind of work + +1:42:42.360 --> 1:42:44.360 + and they have a responsibility + +1:42:44.360 --> 1:42:46.360 + to consider the consequences + +1:42:46.360 --> 1:42:49.360 + and to think about things like + +1:42:49.360 --> 1:42:53.360 + how will humans be in the loop here? + +1:42:53.360 --> 1:42:55.360 + How do we avoid runaway feedback loops? + +1:42:55.360 --> 1:42:58.360 + How do we ensure an appeals process for humans + +1:42:58.360 --> 1:43:00.360 + that are impacted by my algorithm? + +1:43:00.360 --> 1:43:04.360 + How do I ensure that the constraints of my algorithm + +1:43:04.360 --> 1:43:08.360 + are adequately explained to the people that end up using them? + +1:43:08.360 --> 1:43:11.360 + There's all kinds of human issues, + +1:43:11.360 --> 1:43:13.360 + which only data scientists + +1:43:13.360 --> 1:43:17.360 + are actually in the right place to educate people about, + +1:43:17.360 --> 1:43:21.360 + but data scientists tend to think of themselves as + +1:43:21.360 --> 1:43:22.360 + just engineers + +1:43:22.360 --> 1:43:24.360 + and that they don't need to be part of that process, + +1:43:24.360 --> 1:43:26.360 + which is wrong. + +1:43:26.360 --> 1:43:29.360 + Well, you're in the perfect position to educate them better, + +1:43:29.360 --> 1:43:32.360 + to read literature, to read history, + +1:43:32.360 --> 1:43:35.360 + to learn from history. + +1:43:35.360 --> 1:43:38.360 + Well, Jeremy, thank you so much for everything you do + +1:43:38.360 --> 1:43:40.360 + for inspiring a huge amount of people, + +1:43:40.360 --> 1:43:42.360 + getting them into deep learning + +1:43:42.360 --> 1:43:44.360 + and having the ripple effects, + +1:43:44.360 --> 1:43:48.360 + the flap of a butterfly's wings that will probably change the world. + +1:43:48.360 --> 1:44:17.360 + So thank you very much. +