def __init__(self, exp_dict):
        super().__init__()
        self.backbone = models.vgg16(
            pretrained=exp_dict["imagenet_pretraining"], progress=True)
        num_ftrs = self.backbone.classifier[-1].in_features
        self.backbone.classifier[-1] = torch.nn.Linear(num_ftrs,
                                                       exp_dict["num_classes"])
        self.backbone = patch_module(self.backbone)
        self.initial_weights = deepcopy(self.backbone.state_dict())
        self.backbone.cuda()

        self.batch_size = exp_dict['batch_size']
        self.calibrate = exp_dict.get('calibrate', False)
        self.learning_epoch = exp_dict['learning_epoch']
        self.optimizer = torch.optim.SGD(self.backbone.parameters(),
                                         lr=exp_dict['lr'],
                                         weight_decay=5e-4,
                                         momentum=0.9,
                                         nesterov=True)

        self.criterion = CrossEntropyLoss()
        shuffle_prop = exp_dict.get('shuffle_prop', 0.0)
        max_sample = -1
        self.heuristic = get_heuristic(exp_dict['heuristic'],
                                       shuffle_prop=shuffle_prop)
        self.wrapper = ModelWrapper(self.backbone, criterion=self.criterion)
        self.wrapper.add_metric(
            'cls_report',
            lambda: ClassificationReport(exp_dict["num_classes"]))
        self.wrapper.add_metric('accuracy', lambda: Accuracy())
        self.loop = ActiveLearningLoop(None,
                                       self.wrapper.predict_on_dataset,
                                       heuristic=self.heuristic,
                                       ndata_to_label=exp_dict['query_size'],
                                       batch_size=self.batch_size,
                                       iterations=exp_dict['iterations'],
                                       use_cuda=True,
                                       max_sample=max_sample)

        self.calib_set = get_dataset('calib', exp_dict['dataset'])
        self.valid_set = get_dataset('val', exp_dict['dataset'])
        self.calibrator = DirichletCalibrator(
            self.wrapper,
            exp_dict["num_classes"],
            lr=0.001,
            reg_factor=exp_dict['reg_factor'],
            mu=exp_dict['mu'])

        self.active_dataset = None
        self.active_dataset_settings = None
Пример #2
0
 def _build_model(self):
     # We use `patch_module` to swap Dropout modules in the model
     # for our implementation which enables MC-Dropou
     self.vgg16 = patch_module(vgg16(num_classes=self.hparams.num_classes))
Пример #3
0
def main():
    args = parse_args()
    use_cuda = torch.cuda.is_available()
    torch.backends.cudnn.benchmark = True
    random.seed(1337)
    torch.manual_seed(1337)
    if not use_cuda:
        print("warning, the experiments would take ages to run on cpu")

    hyperparams = vars(args)

    active_set, test_set = get_datasets(hyperparams["initial_pool"])

    heuristic = get_heuristic(hyperparams["heuristic"],
                              hyperparams["shuffle_prop"])
    criterion = CrossEntropyLoss()
    model = vgg16(pretrained=False, num_classes=10)
    weights = load_state_dict_from_url(
        "https://download.pytorch.org/models/vgg16-397923af.pth")
    weights = {k: v for k, v in weights.items() if "classifier.6" not in k}
    model.load_state_dict(weights, strict=False)

    # change dropout layer to MCDropout
    model = patch_module(model)

    if use_cuda:
        model.cuda()
    optimizer = optim.SGD(model.parameters(),
                          lr=hyperparams["lr"],
                          momentum=0.9)

    # Wraps the model into a usable API.
    model = ModelWrapper(model, criterion)

    logs = {}
    logs["epoch"] = 0

    # for prediction we use a smaller batchsize
    # since it is slower
    active_loop = ActiveLearningLoop(
        active_set,
        model.predict_on_dataset,
        heuristic,
        hyperparams.get("query_size", 1),
        batch_size=10,
        iterations=hyperparams["iterations"],
        use_cuda=use_cuda,
    )
    # We will reset the weights at each active learning step.
    init_weights = deepcopy(model.state_dict())

    for epoch in tqdm(range(args.epoch)):
        # Load the initial weights.
        model.load_state_dict(init_weights)
        model.train_on_dataset(
            active_set,
            optimizer,
            hyperparams["batch_size"],
            hyperparams["learning_epoch"],
            use_cuda,
        )

        # Validation!
        model.test_on_dataset(test_set, hyperparams["batch_size"], use_cuda)
        metrics = model.metrics
        should_continue = active_loop.step()
        if not should_continue:
            break

        val_loss = metrics["test_loss"].value
        logs = {
            "val": val_loss,
            "epoch": epoch,
            "train": metrics["train_loss"].value,
            "labeled_data": active_set.labelled,
            "Next Training set size": len(active_set),
        }
        print(logs)
Пример #4
0
def main():
    args = parse_args()
    use_cuda = torch.cuda.is_available()
    torch.backends.cudnn.benchmark = True
    random.seed(1337)
    torch.manual_seed(1337)
    if not use_cuda:
        print("warning, the experiments would take ages to run on cpu")

    hyperparams = vars(args)

    heuristic = get_heuristic(hyperparams['heuristic'],
                              hyperparams['shuffle_prop'])

    model = BertForSequenceClassification.from_pretrained(
        pretrained_model_name_or_path=hyperparams["model"])
    tokenizer = BertTokenizer.from_pretrained(
        pretrained_model_name_or_path=hyperparams["model"])

    # In this example we use tokenizer once only in the beginning since it would
    # make the whole process faster. However, it is also possible to input tokenizer
    # in trainer.
    active_set, test_set = get_datasets(hyperparams['initial_pool'], tokenizer)

    # change dropout layer to MCDropout
    model = patch_module(model)

    if use_cuda:
        model.cuda()

    init_weights = deepcopy(model.state_dict())

    training_args = TrainingArguments(
        output_dir='/app/baal/results',  # output directory
        num_train_epochs=hyperparams['learning_epoch'],  # total # of training epochs
        per_device_train_batch_size=16,  # batch size per device during training
        per_device_eval_batch_size=64,  # batch size for evaluation
        weight_decay=0.01,  # strength of weight decay
        logging_dir='/app/baal/logs',  # directory for storing logs
    )

    # We wrap the huggingface Trainer to create an Active Learning Trainer
    model = BaalTransformersTrainer(model=model,
                                    args=training_args,
                                    train_dataset=active_set,
                                    eval_dataset=test_set,
                                    tokenizer=None)

    logs = {}
    logs['epoch'] = 0

    # In this case, nlp data is fast to process and we do NoT need to use a smaller batch_size
    active_loop = ActiveLearningLoop(active_set,
                                     model.predict_on_dataset,
                                     heuristic,
                                     hyperparams.get('n_data_to_label', 1),
                                     iterations=hyperparams['iterations'])

    for epoch in tqdm(range(args.epoch)):
        # we use the default setup of HuggingFace for training (ex: epoch=1).
        # The setup is adjustable when BaalHuggingFaceTrainer is defined.
        model.train()

        # Validation!
        eval_metrics = model.evaluate()

        # We reorder the unlabelled pool at the frequency of learning_epoch
        # This helps with speed while not changing the quality of uncertainty estimation.
        should_continue = active_loop.step()

        # We reset the model weights to relearn from the new trainset.
        model.load_state_dict(init_weights)
        model.lr_scheduler = None
        if not should_continue:
            break
        active_logs = {"epoch": epoch,
                       "labeled_data": active_set._labelled,
                       "Next Training set size": len(active_set)}

        logs = {**eval_metrics, **active_logs}
        print(logs)
Пример #5
0
    def __init__(self, active_dataset: ActiveLearningDataset,
                 hparams: Namespace, network: nn.Module):
        super().__init__(active_dataset, hparams, network)

        self.network = patch_module(self.network)
Пример #6
0
# Uses an ActiveLearningDataset to help us split labelled and unlabelled examples.
al_dataset = ActiveLearningDataset(
    train_ds, pool_specifics={"transform": test_transform})
al_dataset.label_randomly(200)  # Start with 200 items labelled.

# Creates an MLP to classify MNIST
model = nn.Sequential(
    nn.Flatten(),
    nn.Linear(784, 512),
    nn.Dropout(),
    nn.Linear(512, 512),
    nn.Dropout(),
    nn.Linear(512, 10),
)
model = patch_module(model)  # Set dropout layers for MC-Dropout.
if use_cuda:
    model = model.cuda()
wrapper = ModelWrapper(model=model, criterion=nn.CrossEntropyLoss())
optimizer = optim.SGD(model.parameters(),
                      lr=0.001,
                      momentum=0.9,
                      weight_decay=5e-4)

# We will use BALD as our heuristic as it is a great tradeoff between performance and efficiency.
bald = BALD()
# Setup our active learning loop for our experiments
al_loop = ActiveLearningLoop(
    dataset=al_dataset,
    get_probabilities=wrapper.predict_on_dataset,
    heuristic=bald,