JESC: Japanese-English Subtitle Corpus.

In this paper we describe the Japanese-English Subtitle Corpus (JESC). JESCis a large Japanese-English parallel corpus covering the underrepresenteddomain of conversational dialogue. It consists of more than 3.2 millionexamples, making it the largest freely available dataset of its kind. Thecorpus was assembled by crawling and aligning subtitles found on the web. Theassembly process incorporates a number of novel preprocessing elements toensure high monolingual fluency and accurate bilingual alignments. We summarizeits contents and evaluate its quality using human experts and baseline machinetranslation (MT) systems.