Linguistic-based computational treatment of textual entailment recognition

In this thesis, I investigate how lexical resources based on the organisation of lexical knowledge in classes which share common (syntactic, semantic, etc.) features support natural language processing and in particular symbolic recognition of textual entailment. First, I present a robust and wide coverage approach to lexico-structural verb paraphrase recognition based on Levin\u27s (1993) classification of English verbs. Then, I show that by extending Levin\u27s framework to general inference patterns, a classification of English adjectives can be obtained that compared with previous approaches, provides a more fine grained semantic characterisation of their inferential properties. Further, I develop a compositional semantic framework to assign a semantic representation to adjectives based on an ontologically promiscuous approach (Hobbs, 1985) and thereby supporting first order inference for all types of adjectives including extensional ones. Finally, I present a test suite for adjectival inference I developed as a resource for the evaluation of computational systems handling natural language inference.In der vorliegenden Dissertation habe ich untersucht, wie lexikalische Ressourcen, die auf der Gliederung lexikalischen Wissens in Klassen mit gemeinsamen Eigenschaften (lexikalische, semantische etc,) basieren, die computergestützte Verarbeitung natürlicher Sprache und insbesondere die symbolische Erkennung von Entailment unterstützen. Basierend auf Levins (1993) Klassifikation englischer Verben, wurde zuerst ein robuster, für die Verarbeitung beliebiger Texte geeigneter Ansatz zur Paraphrasenerkennung vorgestellt. Dann habe ich aufgezeigt, dass man durch eine Erweiterung von Levins Systematik zur Behandlung allgemeiner Inferenzmuster, eine Klassifikation von englischen Adjektiven erhält, die verglichen mit früheren Ansätzen, eine feinkörnige semantische Charakterisierung ihrer inferentiellen Eigenschaften gestattet und so die Basis für die computergestützte Behandlung von Inferenz bei Adjektiven bildet. Ein anderes beachtliches Ergebnis der vorliegenden Arbeit ist die Test Suite, die ich entwickelt habe und die als Ressource für NPL Anwendungen, die Inferenzen (insbesondere Inferenzen bei Adjektiven) behandeln, genutzt werden kann. Durch die Konstruktion dieser Test Suite beabsichtige ich, den Weg für die Schaffung von Ressourcen zu ebnen, die einen tieferen Einblick in die für Inferenz verantwortlichen Phänomene ermöglichen

A test suite for inference involving adjectives

International audienceRecently, most of the research in NLP has concentrated on the creation of applications coping with textual entailment. However, there still exist very few resourses for the evaluation of such applications. We argue that the reason for this resides not only in the novelty of the research field but also and mainly in the difficulty of defining the linguistic phenomena which are responsible for inference. As the TSNLP project has shown test suites provide an optimal diagnostic and evaluation tools for NLP applications, as contrary to text corpora they provide a deep insight in the linguistic phenomena allowing control over the data. Thus in this paper, we present a test suite specifically developed for studying inference problems shown by English adjectives. The construction of the test suite is based on the deep linguistic analysis and following classification of entailment patterns of adjectives and follows the TSNLP guidelines on linguistic databases providing a clear coverage, systematic annotation of inference tasks, large reusability and simple maintenance. With the design of this test suite we aim at creating a resource supporting the evaluation of computational systems handling natural language inference and in particular at providing a benchmark against which to evaluate and compare existing semantic analysers

Paraphrastic grammars

Colloque avec actes et comité de lecture. nationale.National audienceArguably, grammars which associate natural language expressions not only with a syntactic but also with a semantic representation, should do so in a way that capture paraphrasing relations between sentences whose core semantics are equivalent. Yet existing semantic grammars fail to do so. In this paper, we describe an ongoing project whose aim is the production of a ``paraphrastic grammar'' that is, a grammar which associates paraphrases with identical semantic representations. We begin by proposing a typology of paraphrases. We then show how this typology can be used to simultaneously guide the development of a grammar and of a testsuite designed to support the evaluation of this grammar

Using set constraints to generate distinguishing descriptions

Colloque avec actes et comité de lecture. internationale.International audienceThe incremental algorithm introduced in DalRei95 for producing distinguishing descriptions does not always generate a minimal description. In this paper, I show that when generalised to sets of individuals and disjunctive properties, this approach might generate unnecessarily long and ambiguous and/or epistemically redundant descriptions. I then present an alternative, constraint-based algorithm and show that it builds on existing related algorithms in that (i) it produces minimal descriptions for sets of individuals using positive, negative and disjunctive properties, (ii) it straightforwardly generalises to n-ary relations and (iii) it is integrated with surface realisation

A Serious Game for Second Language Acquisition in a Virtual Environment

International audienceIn this paper, we present I-FLEG, a 3D language game designed for interactively learning French as a second language. I-FLEG differs from previous computer-aided language learning (CALL) approaches in that it combines a situated, language learning environment with advanced artificial intelligence and natural language generation techniques which support user adaptivity and the automatic, context-aware generation of learning material. In addition, because it is integrated in a 3D virtual reality environment, I-FLEG naturally supports elearning and facilitates the collection of test data

Reconnaissance d'implications textuelles à forte composante linguistique

In this thesis, I investigate how lexical resources based on the organisation of lexical knowledge in classes which share common (syntactic, semantic, etc.) features support natural language processing and in particular symbolic recognition of textual entailment. First, I present a robust and wide coverage approach to lexico-structural verb paraphrase recognition based on Levin's (1993) classification of English verbs. Then, I show that by extending Levin's framework to general inference patterns, a classification of English adjectives can be obtained that compared with previous approaches, provides a more fine grained semantic characterisation of their inferential properties. Further, I develop a compositional semantic framework to assign a semantic representation to adjectives based on an ontologically promiscuous approach \citep{Hobbs85} and thereby supporting first order inference for all types of adjectives including extensional ones. Finally, I present a test suite for adjectival inference I developed as a resource for the evaluation of computational systems handling natural language inference.Dans cette thèse, j'étudie la manière dont les ressources lexicales basées sur l'organisation de la connaissance lexicale dans des classes qui partagent des propriétés communes (syntactiques, sémantiques, etc.) permettent le traitement automatique de la langue naturelle et en particulier la reconnaissance symbolique d'implications textuelles. Tout d'abord, je présente une approche robuste et à large couverture sur la reconnaissance de paraphrases verbales lexico-structurelle basée sur la classification de verbes anglais par Levin. Puis, je montre qu'en étendant le cadre proposé par Levin pour traiter les modèles d'inférence généraux, on obtient une classification d'adjectifs anglais qui, comparée à des approches antérieures, propose une caractérisation sémantique à grain plus fin de leurs propriétés déductives. De plus, je développe un cadre sémantique compositionnel pour assigner à des adjectifs une représentation sémantique sur la base d'une approche ontologiquement variée (Hobbs85) et qui permet ainsi l'inférence de premier ordre pour tous les types d'adjectifs, y compris les adjectifs extensionnels. Enfin, je présente un corpus de test pour l'inférence basée sur les adjectifs que j'ai développée comme ressource pour l'évaluation de systèmes de traitement automatique de l'inférence de la langue naturelle

Linguistik-basierter komputationeller Ansatz zur Erkennung textueller Inferenz

In this thesis, I investigate how lexical resources based on the organisation of lexical knowledge in classes which share common (syntactic, semantic, etc.) features support natural language processing and in particular symbolic recognition of textual entailment. First, I present a robust and wide coverage approach to lexico-structural verb paraphrase recognition based on Levin's (1993) classification of English verbs. Then, I show that by extending Levin's framework to general inference patterns, a classification of English adjectives can be obtained that compared with previous approaches, provides a more fine grained semantic characterisation of their inferential properties. Further, I develop a compositional semantic framework to assign a semantic representation to adjectives based on an ontologically promiscuous approach (Hobbs, 1985) and thereby supporting first order inference for all types of adjectives including extensional ones. Finally, I present a test suite for adjectival inference I developed as a resource for the evaluation of computational systems handling natural language inference.In der vorliegenden Dissertation habe ich untersucht, wie lexikalische Ressourcen, die auf der Gliederung lexikalischen Wissens in Klassen mit gemeinsamen Eigenschaften (lexikalische, semantische etc,) basieren, die computergestützte Verarbeitung natürlicher Sprache und insbesondere die symbolische Erkennung von Entailment unterstützen. Basierend auf Levins (1993) Klassifikation englischer Verben, wurde zuerst ein robuster, für die Verarbeitung beliebiger Texte geeigneter Ansatz zur Paraphrasenerkennung vorgestellt. Dann habe ich aufgezeigt, dass man durch eine Erweiterung von Levins Systematik zur Behandlung allgemeiner Inferenzmuster, eine Klassifikation von englischen Adjektiven erhält, die verglichen mit früheren Ansätzen, eine feinkörnige semantische Charakterisierung ihrer inferentiellen Eigenschaften gestattet und so die Basis für die computergestützte Behandlung von Inferenz bei Adjektiven bildet. Ein anderes beachtliches Ergebnis der vorliegenden Arbeit ist die Test Suite, die ich entwickelt habe und die als Ressource für NPL Anwendungen, die Inferenzen (insbesondere Inferenzen bei Adjektiven) behandeln, genutzt werden kann. Durch die Konstruktion dieser Test Suite beabsichtige ich, den Weg für die Schaffung von Ressourcen zu ebnen, die einen tieferen Einblick in die für Inferenz verantwortlichen Phänomene ermöglichen

I-FLEG: A 3D-Game for Learning French.

International audienceIn this paper, we present I-FLEG, a serious language game designed for interactively learning French as a second language. The game is integrated in Second Life and exploits the 3D virtual reality environment provided by this platform to implement immersive, learn-by-doing techniques that have proved to be among the most effective learning strategies in second language acquisition. Furthermore, the integration of the game in Second Life permits to fulfill many important desiderata of computer-aided learning technology. It allows ubiquitous, long distance learning as well as universal access. In addition, these characteristics by facilitating the collection of big amounts of test data over the web render our game an ideal device for both monitoring learner performance in dependence on situational context factors and for comparing different teaching technologies

A Test Suite for Inference Involving Adjectives

Recently, most of the research in NLP has concentrated on the creation of applications coping with textual entailment. However, there still exist very few resourses for the evaluation of such applications. We argue that the reason for this resides not only in the novelty of the research field but also and mainly in the difficulty of defining the linguistic phenomena which are responsible for inference. As the TSNLP project has shown test suites provide an optimal diagnostic and evaluation tools for NLP applications, as contrary to text corpora they provide a deep insight in the linguistic phenomena allowing control over the data. Thus in this paper, we present a test suite specifically developed for studying inference problems shown by English adjectives. The construction of the test suite is based on the deep linguistic analysis and following classification of entailment patterns of adjectives and follows the TSNLP guidelines on linguistic databases providing a clear coverage, systematic annotation of inference tasks, large reusability and simple maintenance. With the design of this test suite we aim at creating a resource supporting the evaluation of computational systems handling natural language inference and in particular at providing a benchmark against which to evaluate and compare existing semantic analysers. 1

Recognition of alternation paraphrases: a robust and exhaustive symbolic approach

In this paper we show how by incorporating linguistic knowledge in a shallow parser like XIP, it is possible to build a robust semantic parser which can cope with paraphrastic constructions involving alternations and/or lexical synonymy. The robustness of the parser is dependent on the amount of linguistic knowledge at disposal. For the moment, we have incorporated the VerbNet verb lexicon in our parser, so that it can recognise verb synonymy and meaning preserving alternations of declarative sentences. In the future, we want to extend the parser taking into consideration grammatical variations of declarative sentences and more complex cases of paraphrastic constructions, such as nominalisations and noun phrase-adjective substitution