POS tagging, lemmatization and dependency parsing of West Frisian

TL;DR

This paper introduces a comprehensive NLP pipeline for West Frisian, including POS tagging, lemmatization, and dependency parsing, built on a newly annotated corpus and leveraging Dutch translation techniques.

Contribution

It presents the first integrated lemmatizer, POS-tagger, and dependency parser for West Frisian, utilizing a novel annotated corpus and translation-based annotation methods.

Findings

Significant improvement in lemmatization accuracy.

Effective use of Dutch translation for annotation.

The tools are available as a web app and web service.

Abstract

We present a lemmatizer/POS-tagger/dependency parser for West Frisian using a corpus of 44,714 words in 3,126 sentences that were annotated according to the guidelines of Universal Dependency version 2. POS tags were assigned to words by using a Dutch POS tagger that was applied to a literal word-by-word translation, or to sentences of a Dutch parallel text. Best results were obtained when using literal translations that were created by using the Frisian translation program Oersetter. Morphologic and syntactic annotations were generated on the basis of a literal Dutch translation as well. The performance of the lemmatizer/tagger/annotator when it was trained using default parameters was compared to the performance that was obtained when using the parameter values that were used for training the LassySmall UD 2.5 corpus. A significant improvement was found for `lemma'. The Frisian lemmatizer/PoS tagger/dependency parser is released as a web app and as a web service.