Flair: Train a NER using BILOU tags

[omri374]

Hi,
I'm evaluating Flair and so far it's very cool!
I have a dataset which is already annotated as BILOU. I can technically translate it to BIO but was wondering if it should or shouldn't work off the shelf with BILOU tags.

Thanks!

[pommedeterresautee]

You can replace BIEOS which is managed by Flair

        annotations = [a.replace('L-', 'E-') for a in annotations]
        annotations = [a.replace('U-', 'S-') for a in annotations]

(for Spacy annotations)

[omri374]

Thanks.
If I train a SequenceTagger with pretrained embeddings, does it matter which annotation scheme I use? Does the model use any external data to the training data I provide it with?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[WiraDKP]

Hi @pommedeterresautee
I have confirmed that BIEOS works.

In the other hand, would it be a problem if someone uses BIO scheme?

[djstrong]

No problem with other schemes, but some may achieve better results.

[WiraDKP]

Thanks @djstrong

I have just confirmed that using BIO works as well.
I hope this info could be useful as reference for future user.

Here is the summary to train NER with BILOU tags using Flair:

• you could convert BILOU to BIEOS

annotations = [a.replace('L-', 'E-') for a in annotations]
annotations = [a.replace('U-', 'S-') for a in annotations]

• you could convert BILOU to BIO

annotations = [a.replace('L-', 'I-') for a in annotations]
annotations = [a.replace('U-', 'B-') for a in annotations]

We can close the thread now.