This paper presents the results of the shared tasks from the 6th workshop on Asian translation (WAT2019) including Ja↔En, Ja↔Zh scientific paper translation subtasks, Ja↔En, Ja↔Ko, Ja↔En patent translation subtasks, Hi↔En, My↔En, Km↔En, Ta↔En mixed domain subtasks, Ru↔Ja news commentary translation task, and En→Hi multi-modal translation task. For the WAT2019, 25 teams participated in the shared tasks. We also received 10 research paper submissions out of which 7 1 were accepted. About 400 translation results were submitted to the automatic evaluation server, and selected submissions were manually evaluated.

This paper presents the results of the shared tasks from the 8th workshop on Asian translation (WAT2021). For the WAT2021, 28 teams participated in the shared tasks and 24 teams submitted their translation results for the human evaluation. We also accepted 5 research papers. About 2,100 translation results were submitted to the automatic evaluation server, and selected submissions were manually evaluated.

Recent work on machine translation has used crowdsourcing to reduce costs of manual evaluations. However, crowdsourced judgments are often biased and inaccurate. In this paper, we present a statistical model that aggregates many manual pairwise comparisons to robustly measure a machine translation system's performance. Our method applies graded response model from item response theory (IRT), which was originally developed for academic tests. We conducted experiments on a public dataset from the Workshop on Statistical Machine Translation 2013, and found that our approach resulted in highly interpretable estimates and was less affected by noisy judges than previously proposed methods.

In the literature, two main categories of methods have been proposed for bilingual lexicon extraction from comparable corpora, namely topic model and context based methods. In this paper, we present a bilingual lexicon extraction system that is based on a novel combination of these two methods in an iterative process. Our system does not rely on any prior knowledge and the performance can be iteratively improved. To the best of our knowledge, this is the first study that iteratively exploits both topical and contextual knowledge for bilingual lexicon extraction. Experiments conduct on Chinese-English and Japanese-English Wikipedia data show that our proposed method performs significantly better than a state-of-the-art method that only uses topical knowledge.

Parallel corpora are crucial for statistical machine translation (SMT); however, they are quite scarce for most language pairs and domains. As comparable corpora are far more available, many studies have been conducted to extract either parallel sentences or fragments from them for SMT. In this article, we propose an integrated system to extract both parallel sentences and fragments from comparable corpora. We first apply parallel sentence extraction to identify parallel sentences from comparable sentences. We then extract parallel fragments from the comparable sentences. Parallel sentence extraction is based on a parallel sentence candidate filter and classifier for parallel sentence identification. We improve it by proposing a novel filtering strategy and three novel feature sets for classification. Previous studies have found it difficult to accurately extract parallel fragments from comparable sentences. We propose an accurate parallel fragment extraction method that uses an alignment model to locate the parallel fragment candidates and an accurate lexicon-based filter to identify the truly parallel fragments. A case study on the Chinese--Japanese Wikipedia indicates that our proposed methods outperform previously proposed methods, and the parallel data extracted by our system significantly improves SMT performance.

Abstract. Katakana, Japanese phonogram mainly used for loan words, is a trou-blemaker in Japanese word segmentation. Since Katakana words are heavily domain-dependent and there are many Katakana neologisms, it is almost impossible to construct and maintain Katakana word dictionary by hand. This paper proposes an automatic segmentation method of Japanese Katakana compounds, which makes it possible to construct precise and concise Katakana word dictionary automati-cally, given only a medium or large size of Japanese corpus of some domain.

This paper introduces the KyotoEBMT Example-Based Machine Translation framework. Our system uses a tree-to-tree approach, employing syntactic dependency analysis for both source and target languages in an attempt to preserve non-local structure. The effectiveness of our system is maximized with online example matching and a flexible decoder. Evaluation demonstrates BLEU scores competitive with state-of-the-art SMT systems such as Moses. The current implementation is intended to be released as open-source in the near future.

While the progress of machine translation of written text has come far in the past several years thanks to the increasing availability of parallel corpora and corpora-based training technologies, automatic translation of spoken text and dialogues remains challenging even for modern systems. In this paper, we aim to boost the machine translation quality of conversational texts by introducing a newly constructed Japanese-English business conversation parallel corpus. A detailed analysis of the corpus is provided along with challenging examples for automatic translation. We also experiment with adding the corpus in a machine translation training scenario and show how the resulting system benefits from its use.