Multilingual NER Transfer for Low-resource Languages

In massively multilingual transfer NLP models over many source languages are applied to a low-resource target language. In contrast to most prior work, which use a single model or a small handful, we consider many such models, which raises the critical problem of poor transfer, particularly from distant languages. We propose two techniques for modulating the transfer: one based on unsupervised truth inference, and another using limited supervision in the target language. Evaluating on named entity recognition over 41 languages, we show that our techniques are much more effective than strong baselines, including standard ensembling, and our unsupervised method rivals oracle selection of the single best individual model.