如何通过ktrain文本分类器使用另一个预训练的BERT模型?

时间:2020-09-03 17:43:15

标签: python bert-language-model ktrain

如何为ktrain库中的文本分类器使用其他预训练模型?使用时:

model = text.text_classifier('bert',(x_train,y_train), preproc = preproc)

This uses the multilangual pretrained model

但是,我也想尝试一种单语模型。即荷兰语:“ wietsedv / bert-base-dutch-cased”,也用于其他k列实现for example

但是,当尝试在文本分类器中使用此命令时,它不起作用:

model = text.text_classifier('bert', (x_train, y_train) ,
> preproc=preproc, bert_model='wietsedv/bert-base-dutch-cased')

model = text.text_classifier('wietsedv/bert-base-dutch-cased', (x_train, y_train), preproc=preproc)

有人可以这样做吗?谢谢!

1 个答案:

答案 0 :(得分:2)

ktrain 中有两个文本分类API。第一个是text_classifier API,可用于选择数量的变压器模型和非变压器模型。第二个是Transformer API,可与任何transformers模型一起使用,包括您列出的模型。

后者在this tutorial notebookthis medium article中有详细说明。

例如,您可以在以下示例中将MODEL_NAME替换为所需的任何模型:

示例:

# load text data
categories = ['alt.atheism', 'soc.religion.christian','comp.graphics', 'sci.med']
from sklearn.datasets import fetch_20newsgroups
train_b = fetch_20newsgroups(subset='train', categories=categories, shuffle=True)
test_b = fetch_20newsgroups(subset='test',categories=categories, shuffle=True)
(x_train, y_train) = (train_b.data, train_b.target)
(x_test, y_test) = (test_b.data, test_b.target)

# build, train, and validate model (Transformer is wrapper around transformers library)
import ktrain
from ktrain import text
MODEL_NAME = 'distilbert-base-uncased'  # replace this with model of choice
t = text.Transformer(MODEL_NAME, maxlen=500, class_names=train_b.target_names)
trn = t.preprocess_train(x_train, y_train)
val = t.preprocess_test(x_test, y_test)
model = t.get_classifier()
learner = ktrain.get_learner(model, train_data=trn, val_data=val, batch_size=6)
learner.fit_onecycle(5e-5, 4)
learner.validate(class_names=t.get_classes()) # class_names must be string values

# Output from learner.validate()
#                        precision    recall  f1-score   support
#
#           alt.atheism       0.92      0.93      0.93       319
#         comp.graphics       0.97      0.97      0.97       389
#               sci.med       0.97      0.95      0.96       396
#soc.religion.christian       0.96      0.96      0.96       398
#
#              accuracy                           0.96      1502
#             macro avg       0.95      0.96      0.95      1502
#          weighted avg       0.96      0.96      0.96      1502