Université fédérale du Rio Grande do Sul, Porto Alegre (Brésil)
Invitée du Lattice – mai 2014
En mai 2014, le labex TransferS et le Lattice invitent le Pr. Aline Villavicencio de l’Université fédérale du Rio Grande do Sul, Brésil, spécialiste de l’acquisition du langage et de la modélisation des phénomènes correspondants, pour une série de conférences dispensées en anglais.
Mercredi 7 mai- 10h30-12h30 - ENS, 45 rue d’Ulm - Salle Cartan
Language Acquisition and Probabilistic Models : keeping it simple
Joint work with Bob Berwick (MIT)
Hierarchical Bayesian Models (HBMs) have been used with some success to capture empirically observed patterns of under- and overgeneralization in child language acquisition. However, as is well known, HBMs are « ideal » learning systems, assuming access to unlimited computational resources that may not be available to child language learners. Consequently, it remains crucial to carefully assess the use of HBMs along with alternative, possibly simpler, candidate models. In this talk I describe an evaluation for a language acquisition domain where explicit HBMs have been proposed : the acquisition of English dative constructions. In particular, I present a detailed, empirically-grounded model-selection comparison of HBMs vs. a simpler alternative based on clustering along with maximum likelihood estimation, the linear competition learning (LCL). Results obtained demonstrate that LCL can match HBM model performance without incurring on the high computational costs associated with HBMs.
Mardi 20 mai- 10h00-12h30 - Laboratoire Lattice (1 rue Maurice Arnoux 92120 Montrouge) - Salle 512
Lexical and topological analysis of language acquisition and dissolution
Psycholinguistic studies on language acquisition, organization and dissolution have proposed several hypotheses to explain human processing of language, where factors such as frequency, polysemy and conventionality seem to influence language use. Recent studies have also indicated the impact of gender and age, with differences in language use between boys and girls found in longitudinal data. In this talk I will describe lexical and topological analyses of some target groups, including children for language acquisition, and clinical groups for language dissolution investigations.
Mercredi 21 mai- 10h00-12h30 - Laboratoire Lattice (1 rue Maurice Arnoux 92120 Montrouge) - Salle 512
Multiword expressions in language technology and language acquisition
Conventional ways of transmitting efficiently and concisely complex ideas and concepts in natural language in a particular domain or community often adopt Multiword Expressions (MWE). For example, « an old wives’ tale » as « an idea believed in the past but now known to be wrong ». MWEs are a heterogeneous set that includes various complex phenomena ranging from compound nouns and verb particle constructions to idioms, and have received considerable attention from researchers from a variety of disciplines, such as Linguistics, Psycholinguistics, and Natural Language Processing. Although their importance has long been recognised, their heterogeneous characteristics have proved a challenge to both linguistic and computational analysis. In this talk I examine some of these challenges and present an approach for their automatic identification. I then discuss some applications for their use in language technology and child language acquisition studies.
A language independent framework for Multiword Expressions Identification
A Multiword Expression (MWE) is a sequences whose interpretation crosses the word boundaries (Sag et al., 2002) and include compound nouns (credit card, mountain bike), phrasal verbs (carry on, go by [a name]), compound terms (benign tumor, nuclear fusion), etc. They are an integral part of language, and their importance has long been recognized. However, their heterogeneous characteristics have proved a challenge to both linguistic and computational analysis. In this paper we discuss some of these challenges along with a variety of approaches for semi-automatically finding and handling these expressions.
Aline Villavicencio is a senior lecturer in Computer Sciences at the Federal University of Rio Grande do Sul (Brazil), and a CNPq fellow. She was a visiting Scholar at MIT (USA) from 2011-2012, and at Saarland University in 2012-2013, with PhD and MPhil degrees from the University of Cambridge, UK. Her research has included work on computational language acquisition and grammar engineering for languages such as English and Portuguese.
She has coordinated several projects on these topics, which include collaboration with France, US and Latin American universities. She has organized events including the ACL-2007 and the EACL-2009, 2012 and 2014 Workshop on Cognitive Aspects of Computational Language Acquisition, and the ACL 2003, 2004, 2011, NAACL-2013 and Coling 2010 workshops on Multiword Expressions among others.