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MOSAIKS-1D R 418K 8193 0.738
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TIML 91K 91K 0.802
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Presto R402K 1290.835
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no DW 0.836
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Figure 3: Presto is robust to incomplete inputs . We measured the AUC ROC score of Presto with
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Linear probing (Presto R) on the CropHarvest dataset when no Dynamic World input is passed, and
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with a subset of input months (the x-axis). We plot the performance of MOSAIKS-1D and TIML
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when they receive the full 12 months of input (dashed horizontal lines) - Presto Rrecovered the
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performance of these models given only a subset of input months.
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2.Channel-groups :(T×d)masked values, with d < D
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3.Contiguous timesteps :(t×D)masked values, t < T
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4.Timesteps :(t×D)masked values, with t < T
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For each training instance, we randomly sampled from the above strategies to construct a mask.
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To handle both the categorical and continuous inputs we used the following loss function, which
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balances the continuous and categorical losses for every batch so that each reconstructed value
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receives the same weighting in the final loss: Ltotal=LMSE+λNcat
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NcontLCE.LMSEis the mean squared
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error reconstruction loss used for the continuous values, LCEis the cross entropy loss used for the
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categorical values, Ncontis the number of masked continuous values and Ncatis the number of masked
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categorical values in the batch. λis a hyperparameter, which we set to 2.
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4 Experiments
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In all experiments described below, we use a Presto model with identical encoder and decoder
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configurations (2 attention layers with 8 heads, an embedding size of 128 and an MLP ratio of 4). We
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investigated the effect of different encoder configurations in Table 8.
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For downstream evaluation, we took the encoder-decoder model learned during pre-training and
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discarded the decoder. As in He et al. (2022), we passed a global pool of all the encoder’s output
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tokens to a downstream classifier. We evaluated the performance of three different models: Presto R,
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Presto RF, and Presto FT, defined below.
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6
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Figure 4: We obtained per-image predictions using Presto by computing a mean and standard deviation
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of Presto’s per-pixel outputs, and passing this concatenated vector to a downstream classifier. We
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illustrate this for the EuroSat task.
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•Feature extraction. Rolf et al. (2021) demonstrated the utility of neural networks as feature-
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extractors on top of which computationally efficient classifiers could be trained. Presto Rand
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Presto RFconsist respectively of linear or logistic regressions and random forests trained on
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Presto’s embeddings. Since only the regression/random forest is trained, this a computationally
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efficient method for adapting Presto to a wide range of tasks.
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•Fine-tuning . Presto FTconsists of the Presto encoder, followed by a linear transformation of the
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pooled tokens to the desired outputs. This entire model (the encoder and the linear transformation)
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is fine-tuned on the training data from each evaluation task. We used a subset of the (downstream)
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training data for validation.
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During pre-training, we used a validation task consisting of classifying all points in the CropHarvest
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dataset (Tseng et al., 2021) according to their FAO indicative crop classifications. For this validation
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task, we excluded points used for evaluation (Section 5.1).
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For evaluation, we compared Presto to state-of-the-art task-specific baselines (Section 5). Because
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there are no other global self-supervised models for pixel-timeseries, we adapted MOSAIKS (Rolf
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et al., 2021) for timeseries data by performing convolutions over the temporal rather than spatial
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dimension (MOSAIKS-1D). We used the output features with random forests (MOSAIKS-1D RF)
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and regressions (MOSAIKS-1D R).
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5 Evaluation Tasks & Results
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We evaluated Presto using six evaluation tasks spanning diverse task types, geographic locations (4
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continents and 38 countries), input data modalities, and fine-tuning dataset sizes (Table 1). Whenever
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possible, we benchmarked Presto against the state-of-the-art model for that task.
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Applying Presto to downstream tasks is computationally efficient . While other methods require a
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cluster of GPUs for fine-tuning (Cong et al., 2022), we fine-tuned Presto on a single GPU or CPU.
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For the fuel moisture task described in Section 5.1, fine-tuning Presto took under 6 minutes on a 2017
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MacBook Pro’s CPU. When Presto is used as a feature extractor, simple models can be trained which
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require few parameters to be learned, as we show in Table 2. Even when fully fine-tuned, Presto’s
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small size meant that relatively few parameters needed to be trained (Tables 5 and 6). This makes
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Presto accessible to practitioners, especially those lacking significant computational resources.
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Below, we describe the tasks used to evaluate Presto and discuss Presto’s performance on these tasks.
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5.1 Timeseries Tasks
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•Crop type Segmentation : The CropHarvest (Tseng et al., 2021) evaluation datasets consist of
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binary pixel classification of (i) maize in Kenya, (ii) coffee in Brazil and (iii) cropland in Togo. We
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compared Presto to the baselines provided by CropHarvest and to Task-Informed Meta-Learning
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(TIML, Tseng et al., 2022), which achieved state-of-the-art results on these datasets.
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7
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Table 3: RMSE results on the regression tasks. The literature baselines are not directly comparable,
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since they use different input datasets or private test data (or both). Rao et al. (2020) reported an
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RMSE of 25 on the fuel moisture dataset with a physics-assisted neural network and the algae bloom
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competition winner reported an RMSE of 0.761, indicating our results are within the scope of utility.
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Best results are highlighted blue , with second best results in bold . Models have a high variance in
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performance across tasks, so we calculated the mean difference in RMSE from the linear regression
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baseline across both tasks. Presto performed most consistently, both when used as a feature-extractor
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and when fine-tuned.
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Fuel
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MoistureAlgae
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BloomsMean
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difference
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Linear Regression 28.20 0.850 0%
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Random Forest 23.84 1.249 15.7%
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MOSAIKS-1D RF 28.75 0.972 8.15%
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Presto FT(random init.) 26.07 0.955 2.40%
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Presto FT 25.28 0.815−7.24%
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Presto RF 25.98 0.884−1.94%
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Table 4: Results on the TreeSatAI dataset. We compared Presto to the dataset’s benchmark models.
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The MLPs contain 3 layers (with 563K-723K parameters respectively) and are tuned for this task. We
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froze the Presto encoder’s 402k parameters and trained a random forest on its outputs with default
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scikit-learn hyperparameters.
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Weighted Micro
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Model Data F1 mAP F1 mAP
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MLP
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S110.09 29.42 12.82 33.09
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LightGBM 11.86 32.79 14.07 35.11
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Presto RF 38.34 35.45 40.79 38.64
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MLP
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S251.97 64.19 54.59 65.83
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LightGBM 48.17 61.99 52.52 61.66
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Presto RF 55.29 61.53 58.29 63.31
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•Fuel Moisture : The live fuel moisture dataset (Rao et al., 2020) measures live fuel moisture content
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