UKPLab / emnlp2017-bilstm-cnn-crf

BiLSTM-CNN-CRF architecture for sequence tagging
Apache License 2.0
824 stars 263 forks source link

Training with New Set of Fine grained labels - NER #14

Closed prohit93 closed 6 years ago

prohit93 commented 6 years ago

Hello @nreimers , I really enjoyed going through your work. Could we improve your existing model / code to retrain for say 50 fine grained ner classes ?

nreimers commented 6 years ago

Hi @prohit93 you are asking though questions.

I would use the multi-task BiLSTM implementation. Then you train the model on coarse grain labels first.

After that, you take the base model and train a new classifier for your fine grained labels. The old classifier (softmax or CRF) for the coarse grained tags are no longer needed.

You can also try to run this as a multi task setup and provide data for the coarse grained labels along with the data for your fine grained labels.

However, I'm not certain if you will achieve that much improvement compared to directly training on your dataset with your fine grained labels. Most multi-task frameworks do not yield that much improvement and they are most often beaten by a simple pipeline approach:

This pipeline approach was in all my experiment often much better than more complicated multi-task setups (or transfer learning setups).