Papers › CrossWeigh: Training Named Entity Tagger from Imperfect Annotations

CrossWeigh: Training Named Entity Tagger from Imperfect Annotations

3 Sep 2019IJCNLP 2019 11arXiv:1909.01441archive 2025-07-28

Zihan Wang, Jingbo Shang, Liyuan Liu, Lihao Lu, Jiacheng Liu, Jiawei Han

Everyone makes mistakes. So do human annotators when curating labels for named entity recognition (NER). Such label mistakes might hurt model training and interfere model comparison. In this study, we dive deep into one of the widely-adopted NER benchmark datasets, CoNLL03 NER. We are able to identify label mistakes in about 5.38% test sentences, which is a significant ratio considering that the state-of-the-art test F1 score is already around 93%. Therefore, we manually correct these label mistakes and form a cleaner test set. Our re-evaluation of popular models on this corrected test set leads to more accurate assessments, compared to those on the original test set. More importantly, we propose a simple yet effective framework, CrossWeigh, to handle label mistakes during NER model training. Specifically, it partitions the training data into several folds and train independent NER models to identify potential mistakes in each fold. Then it adjusts the weights of training data accordingly to train the final NER model. Extensive experiments demonstrate significant improvements of plugging various NER models into our proposed framework on three datasets. All implementations and corrected test set are available at our Github repo: https://github.com/ZihanWangKi/CrossWeigh.

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get_tokens_and_labels ZihanWangKi/CrossWeigh/flair_scripts/flair_ner.py official repository ran · our draft was wrong Apache-2.0 (permissive) · 0b89e60ae07e6da6 · report
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Tasks

NERNamed Entity RecognitionNamed Entity Recognition (NER)named-entity-recognition

Datasets

Introduced by this paper, per the archive.

CoNLL++

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Named Entity Recognition (NER) CoNLL 2003 (English) CrossWeigh + Pooled Flair F1 93.43 #22 of 73 Archive leaderboard report
Named Entity Recognition (NER) CoNLL++ CrossWeigh + Pooled Flair F1 94.28 #6 of 11 Archive leaderboard report
Named Entity Recognition (NER) CoNLL++ Pooled Flair F1 94.13 #7 of 11 Archive leaderboard report
Named Entity Recognition (NER) WNUT 2017 CrossWeigh + Pooled Flair F1 50.03 #16 of 23 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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