In plain words: Inflected forms like walks and walked are grouped under one base word by merging those close in both meaning and spelling, with no labeled examples. Across 23 languages, this beat the standard approach on 23 of 28 test sets.
Abstract
We focus on the task of unsupervised lemmatization, i.e. grouping together inflected forms of one word under one label (a lemma) without the use of annotated training data. We propose to perform agglomerative clustering of word forms with a novel distance measure. Our distance measure is based on the observation that inflections of the same word tend to be similar both string-wise and in meaning. We therefore combine word embedding cosine similarity, serving as a proxy to the meaning similarity, with Jaro-Winkler edit distance. Our experiments on 23 languages show our approach to be promising, surpassing the baseline on 23 of the 28 evaluation datasets.
Rudolf Rosa, Zdeněk Žabokrtský
arXiv:1908.08528 · cs.CL · submitted Aug 22, 2019
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