medcat.config_meta_cat

Module Contents

Classes

General

The General part of the MetaCAT config

Model

The model part of the metaCAT config

Train

The train part of the metaCAT config

ConfigMetaCAT

The MetaCAT part of the config

class medcat.config_meta_cat.General

Bases: medcat.config.MixingConfig, medcat.config.BaseModel

The General part of the MetaCAT config

class Config
extra
validate_assignment = True
device: str = 'cpu'

Device to used by the module to perform predicting/training.

Reference: https://pytorch.org/docs/stable/tensor_attributes.html#torch.device

disable_component_lock: bool = False

Whether to use the MetaCAT component lock.

If set to False (the default), a component lock is used that forces usage only on one thread at a time.

If set to True, the component lock is not used.

seed: int = 13

The seed for random number generation.

NOTE: If used along RelCAT or additional NER, only one of the seeds will take effect NB! For these changes to take effect, the pipe would need to be recreated.

description: str = 'No description'

Should provide a basic description of this MetaCAT model

category_name: medcat.config.Optional[str]

What category is this meta_cat model predicting/training.

NB! For these changes to take effect, the pipe would need to be recreated.

category_value2id: Dict

Map from category values to ID, if empty it will be autocalculated during training

vocab_size: medcat.config.Optional[int]

Will be set automatically if the tokenizer is provided during meta_cat init

lowercase: bool = True

If true all input text will be lowercased

cntx_left: int = 15

Number of tokens to take from the left of the concept

cntx_right: int = 10

Number of tokens to take from the right of the concept

replace_center: medcat.config.Optional[Any]

If set the center (concept) will be replaced with this string

batch_size_eval: int = 5000

Number of annotations to be meta-annotated at once in eval

annotate_overlapping: bool = False

If set meta_anns will be calculated for doc._.ents, otherwise for doc.ents

tokenizer_name: str = 'bbpe'

Tokenizer name used with MetaCAT.

Choose from:
  • ‘bbpe’: Byte Pair Encoding Tokenizer

  • ‘bert-tokenizer’: BERT Tokenizer

NB! For these changes to take effect, the pipe would need to be recreated.

save_and_reuse_tokens: bool = False

This is a dangerous option, if not sure ALWAYS set to False. If set, it will try to share the pre-calculated context tokens between MetaCAT models when serving. It will ignore differences in tokenizer and context size, so you need to be sure that the models for which this is turned on have the same tokenizer and context size, during a deployment.

pipe_batch_size_in_chars: int = 20000000

How many characters are piped at once into the meta_cat class

span_group: medcat.config.Optional[str]

If set, the spacy span group that the metacat model will assign annotations. Otherwise defaults to doc._.ents or doc.ents per the annotate_overlapping settings

class medcat.config_meta_cat.Model

Bases: medcat.config.MixingConfig, medcat.config.BaseModel

The model part of the metaCAT config

class Config
extra
validate_assignment = True
model_name: str = 'lstm'

Model to be used for training or predicting.

Choose from:
  • ‘bert’

  • ‘lstm’

Note

When changing the model, make sure to change the tokenizer accordingly. NB! For these changes to take effect, the pipe would need to be recreated.

model_variant: str = 'bert-base-uncased'

Applicable only when using BERT:

Specifies the model variant to be used.

NB! For these changes to take effect, the pipe would need to be recreated.

model_freeze_layers: bool = True

Applicable only when using BERT:

Determines the training approach for BERT.

  • If True: BERT layers are frozen and only the fully connected (FC) layer(s) on top are trained.

  • If False: Parameter-efficient fine-tuning will be applied using Low-Rank Adaptation (LoRA).

NB! For these changes to take effect, the pipe would need to be recreated.

num_layers: int = 2

Number of layers in the model (both LSTM and BERT)

NB! For these changes to take effect, the pipe would need to be recreated.

input_size: int = 300

Specifies the size of the embedding layer.

Applicable only for LSTM model and ignored for BERT as BERT’s embedding size is predefined.

NB! For these changes to take effect, the pipe would need to be recreated.

hidden_size: int = 300

Number of neurons in the hidden layer.

NB! For these changes to take effect, the pipe would need to be recreated.

dropout: float = 0.5

The dropout for the model.

NB! For these changes to take effect, the pipe would need to be recreated.

phase_number: int = 0

Indicates whether two phase learning is to be used for training.

1: Phase 1 - Train model on undersampled data

2: Phase 2 - Continue training on full data

0: None - 2 phase learning is not performed

Paper reference - https://ieeexplore.ieee.org/document/7533053

category_undersample: str = ''

When using 2 phase learning, this category is used to undersample the data

model_architecture_config: Dict

Specifies the architecture for BERT model.

If fc2 is set to True, then the 2nd fully connected layer is used

If fc2 is True and fc3 is set to True, then the 3rd fully connected layer is used

If lr_scheduler is set to True, then the learning rate scheduler is used with the optimizer

NB! For these changes to take effect, the pipe would need to be recreated.

num_directions: int = 2

Applicable only for LSTM:

2 - bidirectional model, 1 - unidirectional

NB! For these changes to take effect, the pipe would need to be recreated.

nclasses: int = 2

Number of classes that this model will output.

NB! For these changes to take effect, the pipe would need to be recreated.

padding_idx: int

The padding index.

NB! For these changes to take effect, the pipe would need to be recreated.

emb_grad: bool = True

Applicable only for LSTM:

If True, the embeddings will also be trained.

NB! For these changes to take effect, the pipe would need to be recreated.

ignore_cpos: bool = False

If set to True center positions will be ignored when calculating representation

class medcat.config_meta_cat.Train

Bases: medcat.config.MixingConfig, medcat.config.BaseModel

The train part of the metaCAT config

class Config
extra
validate_assignment = True
batch_size: int = 100
nepochs: int = 50
lr: float = 0.001
test_size: float = 0.1
shuffle_data: bool = True

Used only during training, if set the dataset will be shuffled before train/test split

class_weights: medcat.config.Optional[Any]
compute_class_weights: bool = False

If true and class weights not provided, the class weights will be calculated based on the data

score_average: str = 'weighted'

What to use for averaging F1/P/R across labels

prerequisites: dict
cui_filter: medcat.config.Optional[Any]

If set only this CUIs will be used for training

auto_save_model: bool = True

Should do model be saved during training for best results

last_train_on: medcat.config.Optional[int]

When was the last training run

metric: Dict[str, str]

What metric should be used for choosing the best model

loss_funct: str = 'cross_entropy'

Loss function for the model.

Choose from:
  • ‘cross_entropy’

  • ‘focal_loss’

gamma: int = 2

Focal Loss hyperparameter - determines importance the loss gives to hard-to-classify examples

class medcat.config_meta_cat.ConfigMetaCAT

Bases: medcat.config.MixingConfig, medcat.config.BaseModel

The MetaCAT part of the config

class Config
extra
validate_assignment = True
general: General
model: Model
train: Train