"""Model definitions""" import tensorflow as tf from transformers import TFAutoModel class FixMatchTune(tf.keras.Model): """fixmatch""" def __init__( self, encoder_name="readerbench/RoBERT-base", num_classes=4, **kwargs ): super(FixMatchTune,self).__init__(**kwargs) self.bert = TFAutoModel.from_pretrained(encoder_name) self.num_classes = num_classes self.weak_augment = tf.keras.layers.GaussianNoise(stddev=0.5) self.strong_augment = tf.keras.layers.GaussianNoise(stddev=5) self.cls_head = tf.keras.Sequential([ tf.keras.layers.Dense(256,activation="relu"), tf.keras.layers.Dropout(0.2), tf.keras.layers.Dense(64,activation="relu"), tf.keras.layers.Dense(self.num_classes, activation="softmax") ]) def call(self, inputs, training): ids, mask = inputs embeds = self.bert(input_ids=ids, attention_mask=mask,training=training).pooler_output strongs = self.strong_augment(embeds,training=training) weaks = self.weak_augment(embeds,training=training) strong_preds = self.cls_head(strongs,training=training) weak_preds = self.cls_head(weaks,training=training) return weak_preds, strong_preds class MixMatch(tf.keras.Model): """mixmatch""" def __init__(self,bert_model="readerbench/RoBERT-base",num_classes=4,**kwargs): super(MixMatch,self).__init__(**kwargs) self.bert = TFAutoModel.from_pretrained(bert_model) self.num_classes = num_classes self.cls_head = tf.keras.Sequential([ tf.keras.layers.Dense(256,activation="relu"), tf.keras.layers.Dropout(0.2), tf.keras.layers.Dense(64,activation="relu"), tf.keras.layers.Dense(self.num_classes, activation="softmax") ]) self.augment = tf.keras.layers.GaussianNoise(stddev=2) def call(self, inputs, training): ids, mask = inputs embeds = self.bert(input_ids=ids, attention_mask=mask,training=training).pooler_output augs = self.augment(embeds,training=training) return self.cls_head(augs,training=training)