Title: Arabic Multi-Dialect Segmentation: bi-LSTM-CRF vs. SVM,
Abstract: Arabic word segmentation is essential for a variety of NLP applications such
as machine translation and information retrieval. Segmentation entails breaking
words into their constituent stems, affixes and clitics. In this paper, we
compare two approaches for segmenting four major Arabic dialects using only
several thousand training examples for each dialect. The two approaches involve
posing the problem as a ranking problem, where an SVM ranker picks the best
segmentation, and as a sequence labeling problem, where a bi-LSTM RNN coupled
with CRF determines where best to segment words. We are able to achieve solid
segmentation results for all dialects using rather limited training data. We
also show that employing Modern Standard Arabic data for domain adaptation and
assuming context independence improve overall results.