Bruno Cartoni

Lexical Morphology in Machine Translation: A Feasibility Study

This paper presents a feasibility study for implementing lexical morphology principles in a machine translation system in order to solve unknown words. Multilingual symbolic treatment of word-formation is seducing but requires an in-depth analysis of every step that has to be performed. The construction of a prototype is firstly presented, highlighting the methodological issues of such approach. Secondly, an evaluation is performed on a large set of data, showing the benefits and the limits of such approach.

Negation and lexical morphology across languages: insights from a trilingual translation corpus

Abstract This paper proposes an exploratory cross-linguistic bird’s eye-view of negative lexical morphology by examining English, French and Italian negative derivational affixes. More specifically, it aims to uncover the French and Italian equivalents of the English affixes de, dis, in, non, un and less. These include morphological equivalents (i.e. negative prefixes in French and Italian) as well as non-morphological equivalents (i.e. single words devoid of negative affixation, multi-word units or paraphrases). The study relies on a nine-million-word trilingual translation corpus made up of texts from the Europarl corpus and shows that the systematic analysis of translation data makes it possible to identify the major morphological dissimilarities between the three languages investigated. The frequent use of non-morphological translations in French and Italian reflects fundamental differences between the source language (English) and the two target lan-guages (French and Italian), hence pointing to possible translation difficulties. Morphological translations, on the other hand, bring to light cross-linguistic similarities in the use of negative affixes.

Paraphrase Detection in Monolingual Specialized/Lay Comparable Corpora

Paraphrases are a key feature in many natural language processing applications, and their extraction and generation are important tasks to tackle. Given two comparable corpora in the same language and the same domain, but displaying two different discourse types (lay and specialized), specific paraphrases can be spotted which provide a dimension along which these discourse types can be contrasted. Detecting such paraphrases in comparable corpora is the goal of the present work. Generally, paraphrases are identified by means of lexical and/or structural patterns. In this chapter, we present two methods to extract paraphrases across lay and specialized French monolingual comparable corpora. The first method uses lexical patterns designed according to intuition and linguistic studies, while the second is empirical, based on n-gram matching. The two methods appear to be complementary: the n-gram method confirms the initial lexical patterns and identifies other patterns. Besides, differences in the direction of application of paraphrase patterns highlight differences between specialized and lay discourse.