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Sergei Nirenburg - One of the best experts on this subject based on the ideXlab platform.
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CHOICES FOR Lexical Semantics
Computational Intelligence, 2001Co-Authors: Sergei Nirenburg, Victor RaskinAbstract:The modern computational Lexical Semantics has reached a point in its development when it has become useful to compare the goals and methods of the various approaches to it. This article proposes several choices in terms of which these goals and methods can be discussed. It is argued that the central questions include the use of Lexical rules for generating word senses; the role of syntax and formal Semantics in the specification of Lexical meaning; the use of a world model, or ontology, as the organizing principle for Lexical-semantic descriptions; the relation between static and dynamic resources; the commitment to descriptive coverage; the tradeoff between generalization and idiosyncracy; and finally, the adherence to the “supply side” (method-oriented) or “demand side” (task-oriented) ideology of research. The discussion is inspired by, but not limited to, the comparison between the generative lexicon approach and the ontologic semantic approach to Lexical Semantics. It is fair to say that Lexical Semantics, the study of word meaning and of its representation in the lexicon, experienced a powerful resurgence within the last decade. The Lexical Semantics community is quite heterogeneous. It includes former syntacticians, reformed and dyed-in-the-wool formal semanticists, and a considerable chunk of the NLP community. It includes both linguists and computer scientists, some with a strong statistical and probabilistic bent and others pursuing the use of large corpora and MRDs, some actively engaged in developing NLP systems and some others working on designs for the systems of the immediate future. It also includes some “engineer” types who opt to view the field through the prism of an individual concrete application or technique. This article attempts to carry out a comparative analysis of several major directions in Lexical Semantics. Accordingly, this article differs in genre from most “standard” contributions in the field in that instead of describing a particular phenomenon, method, or system, it intends take stock of the field in its current state of development. There is nothing really novel in this genre, since every academic field at a certain stage develops a need for self-assessment in substantive terms. Articles such as this are often couched, overtly or implicitly, as polemics. While the works Chomsky (1959) or Weinreich (1966) could not be called purely theoretical articles, their contribution to the scientific process was outstanding and arguably more important than that of many nonpolemical works. While not competing with these classics, this article follows, as it were, in their footsteps. Our main objective has been to try to tease out the often unstated preferences and differences among the practicioners of Lexical Semantics. Our device for this is to propose a set of issues that we think are important for the field and to try to recreate the attitudes of various researchers toward these issues. By doing so, we may have created a few “straw men” on the way, but no position we will list is without well-recorded support in the community.
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Supply-Side and Demand-Side Lexical Semantics
Breadth and Depth of Semantic Lexicons, 1999Co-Authors: Sergei Nirenburg, Victor RaskinAbstract:Two methodological positions coexist in Lexical Semantics. The supply-side approach selects the topics of research from among the issues that are perceived as those that can be done. It relies on what is perceived as “possible” and “available” with respect to tools and resources. The demand-side places a premium on what must be done to put together a useful working application and, therefore, strives for the comprehensive coverage of a sublanguage/domain in descriptive semantic terms, licensing extensions to its methodology in the process. There are far-reaching consequences in the respective views of the two approaches on such essential issues as the relations between (computational) syntax and (computational) Semantics, the feasibility and status of language-independent ontology as the basis of Lexical Semantics, and the amount of attention to comprehensive semantic description/representation of input text. The distinction between the two approaches is rooted both in the history of linguistics and in the philosophy of science. It is important to understand the two positions in order to match the expectations concerning practical results and declared goals of research in Lexical Semantics.
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SIGLEX Workshop - Syntax-Driven and Ontology-Driven Lexical Semantics
Lexical Semantics and Knowledge Representation, 1992Co-Authors: Sergei Nirenburg, Lori LevinAbstract:We describe the scopes of two schools in Lexical Semantics, which we call syntax-driven Lexical Semantics and ontology-driven Lexical Semantics, respectively. Both approaches are used in various applications at The Center for Machine Translation. We believe that a comparative analysis of these positions and clarification of claims and coverage is essential for the field as a whole.
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syntax driven and ontology driven Lexical Semantics
Meeting of the Association for Computational Linguistics, 1991Co-Authors: Sergei Nirenburg, Lori LevinAbstract:We describe the scopes of two schools in Lexical Semantics, which we call syntax-driven Lexical Semantics and ontology-driven Lexical Semantics, respectively. Both approaches are used in various applications at The Center for Machine Translation. We believe that a comparative analysis of these positions and clarification of claims and coverage is essential for the field as a whole.
Mona Diab - One of the best experts on this subject based on the ideXlab platform.
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improving Lexical Semantics for sentential Semantics modeling selectional preference and similar words in a latent variable model
North American Chapter of the Association for Computational Linguistics, 2013Co-Authors: Mona DiabAbstract:Sentence Similarity [SS] computes a similarity score between two sentences. The SS task differs from document level Semantics tasks in that it features the sparsity of words in a data unit, i.e. a sentence. Accordingly it is crucial to robustly model each word in a sentence to capture the complete semantic picture of the sentence. In this paper, we hypothesize that by better modeling Lexical Semantics we can obtain better sentential Semantics. We incorporate both corpus-based (selectional preference information) and knowledge-based (similar words extracted in a dictionary) Lexical Semantics into a latent variable model. The experiments show state-of-the-art performance among unsupervised systems on two SS datasets.
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HLT-NAACL - Improving Lexical Semantics for Sentential Semantics: Modeling Selectional Preference and Similar Words in a Latent Variable Model
2013Co-Authors: Weiwei Guo, Mona DiabAbstract:Sentence Similarity [SS] computes a similarity score between two sentences. The SS task differs from document level Semantics tasks in that it features the sparsity of words in a data unit, i.e. a sentence. Accordingly it is crucial to robustly model each word in a sentence to capture the complete semantic picture of the sentence. In this paper, we hypothesize that by better modeling Lexical Semantics we can obtain better sentential Semantics. We incorporate both corpus-based (selectional preference information) and knowledge-based (similar words extracted in a dictionary) Lexical Semantics into a latent variable model. The experiments show state-of-the-art performance among unsupervised systems on two SS datasets.
Andrew Koontz-garboden - One of the best experts on this subject based on the ideXlab platform.
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Monotonicity at the Lexical Semantics–morphosyntax interface∗
2015Co-Authors: Andrew Koontz-garbodenAbstract:(2004), the structural side of word formation operations has been well-explored, often to the neglect of the semantic side, which is only recently receiving attention in light of advances made in Lexical Semantics. Work in this area, in my view, should aim to investigate what possible and impossible word formation operations are from a Lexical semantic perspective, and, assuming that the Semantics of word formation is not an “anything goes ” type of system, explain why things are the way they are. That is, the central goal should be to explain why certain types of word formation operations are attested and why others, though conceivable, are not. In this paper, I instantiate this program via examination of how languages encode state and change of state (COS) eventualities, as exemplified by the Quechua data in (1). (1) Quechua (Van Valin 2005:41, due to Weber 1989) a. hatu
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The Lexical Semantics of derived statives
Linguistics and Philosophy, 2011Co-Authors: Andrew Koontz-garbodenAbstract:This paper investigates the Semantics of derived statives, deverbal adjectives that fail to entail there to have been a preceding (temporal) event of the kind named by the verb they are derived from, e.g. in . Building on Gawron's (The Lexical Semantics of extent verbs, San Diego State University, ms, 2009) recent observations regarding the Semantics of extent uses of change of state verbs (e.g., ) and Kennedy and Levin's (Adjectives and adverbs: syntax, Semantics and disclosure, Oxford University Press, Oxford, 2008) theory of change, it is shown, contrary to previous analyses, that a fully compositional semantic analysis is possible, and thus that there is no argument from derived statives for word formation differing from semantic composition above the word level in requiring deletion operations, as in Dubinsky and Simango's (Language 72:749-781, 1996) analysis. Further, such an analysis, by contrast with previous ones, both compositional (Jackson in Resultatives, derived statives, Lexical semantic structure, Doctoral dissertation, UCLA, 2005b; Condoravdi and Deo in Proceedings of the 18th International Congress of Linguists (CIL 18), Seoul, 2008 and non-compositional (Dubinsky and Simango 1996), correctly predicts, as shown by a range of arguments, that the meaning of the derived stative contains the meaning of the verb it is derived from and that it therefore contrasts fundamentally with morphologically simple adjectives in the kind of meaning that it has.
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The Lexical Semantics of derived statives
Linguistics and Philosophy, 2010Co-Authors: Andrew Koontz-garbodenAbstract:This paper investigates the Semantics of derived statives, deverbal adjectives that fail to entail there to have been a preceding (temporal) event of the kind named by the verb they are derived from, e.g. darkened in a darkened portion of skin. Building on Gawron’s (The Lexical Semantics of extent verbs, San Diego State University, ms, 2009) recent observations regarding the Semantics of extent uses of change of state verbs (e.g., Kim’s skin darkens between the knee and the calf) and Kennedy and Levin’s (Measure of change: The adjectival core of degree achievements, Oxford University Press, Oxford, 2008) theory of change, it is shown, contrary to previous analyses, that a fully compositional semantic analysis is possible, and thus that there is no argument from derived statives for word formation differing from semantic composition above the word level in requiring deletion operations, as in Dubinsky and Simango’s (Passive and stative in Chichewa, Language 72:749–781, 1996) analysis. Further, such an analysis, by contrast with previous ones, both compositional (Jackson in Resultatives, derived statives, and Lexical semantic structure, Doctoral dissertation, UCLA, 2005b; Condoravdi and Deo in Proceedings of the 18th International Congress of Linguists (CIL 18), Seoul, 2008) and non-compositional (Dubinsky and Simango 1996), correctly predicts, as shown by a range of arguments, that the meaning of the derived stative contains the meaning of the verb it is derived from and that it therefore contrasts fundamentally with morphologically simple adjectives in the kind of meaning that it has.
Chakaveh Saedi - One of the best experts on this subject based on the ideXlab platform.
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Comparative Probing of Lexical Semantics Theories for Cognitive Plausibility and Technological Usefulness
arXiv: Computation and Language, 2020Co-Authors: António Branco, João António Rodrigues, Malgorzata Salawa, Ruben Branco, Chakaveh SaediAbstract:Lexical Semantics theories differ in advocating that the meaning of words is represented as an inference graph, a feature mapping or a vector space, thus raising the question: is it the case that one of these approaches is superior to the others in representing Lexical Semantics appropriately? Or in its non antagonistic counterpart: could there be a unified account of Lexical Semantics where these approaches seamlessly emerge as (partial) renderings of (different) aspects of a core semantic knowledge base? In this paper, we contribute to these research questions with a number of experiments that systematically probe different Lexical Semantics theories for their levels of cognitive plausibility and of technological usefulness. The empirical findings obtained from these experiments advance our insight on Lexical Semantics as the feature-based approach emerges as superior to the other ones, and arguably also move us closer to finding answers to the research questions above.
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COLING - Comparative Probing of Lexical Semantics Theories for Cognitive Plausibility and Technological Usefulness
Proceedings of the 28th International Conference on Computational Linguistics, 2020Co-Authors: António Branco, João António Rodrigues, Malgorzata Salawa, Ruben Branco, Chakaveh SaediAbstract:Lexical Semantics theories differ in advocating that the meaning of words is represented as an inference graph, a feature mapping or a cooccurrence vector, thus raising the question: is it the case that one of these approaches is superior to the others in representing Lexical Semantics appropriately? Or in its non antagonistic counterpart: could there be a unified account of Lexical Semantics where these approaches seamlessly emerge as (partial) renderings of (different) aspects of a core semantic knowledge base? In this paper, we contribute to these research questions with a number of experiments that systematically probe different Lexical Semantics theories for their levels of cognitive plausibility and of technological usefulness. The empirical findings obtained from these experiments advance our insight on Lexical Semantics as the feature-based approach emerges as superior to the other ones, and arguably also move us closer to finding answers to the research questions above.
Christian Retore - One of the best experts on this subject based on the ideXlab platform.
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An outline of type-theoretical approaches to Lexical Semantics
Journal of Language Modelling, 2017Co-Authors: Robin Cooper, Christian RetoreAbstract:We take the opportunity of the publication of some of the papers of the ESSLLI workshop TYTLES (TYpes Theory and Lexical Semantics, ESSLLI 2015, Barcelona) to provide an overview of the possibilities that type theory offer to model Lexical Semantics, especially the type theoretical frameworks that properly model compositional Semantics.
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Advances in the Logical Representation of Lexical Semantics
arXiv: Computation and Language, 2013Co-Authors: Bruno Mery, Christian RetoreAbstract:The integration of Lexical Semantics and pragmatics in the analysis of the meaning of natural lan- guage has prompted changes to the global framework derived from Montague. In those works, the original lexicon, in which words were assigned an atomic type of a single-sorted logic, has been re- placed by a set of many-facetted Lexical items that can compose their meaning with salient contextual properties using a rich typing system as a guide. Having related our proposal for such an expanded framework \LambdaTYn, we present some recent advances in the logical formalisms associated, including constraints on Lexical transformations and polymorphic quantifiers, and ongoing discussions and research on the granularity of the type system and the limits of transitivity.
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Towards a Type-Theoretical Account of Lexical Semantics
Journal of Logic Language and Information, 2010Co-Authors: Christian Bassac, Bruno Mery, Christian RetoreAbstract:After a quick overview of the field of study known as “Lexical Semantics”, where we advocate the need of accessing additional information besides syntax and Montague- style Semantics at the Lexical level in order to complete the full analysis of an utterance, we summarize the current formulations of a well-known theory of that field. We then propose and justify our own model of the Generative Lexicon Theory, based upon a variation of classical compositional Semantics, and outline its formalization. Additionally, we discuss the theoretical place of informational, knowledge-related data supposed to exist within the lexicon as well as within discourse and other linguistic constructs.
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Towards a Type-Theoretical Account of Lexical Semantics
Journal of Logic Language and Information, 2009Co-Authors: Christian Bassac, Bruno Mery, Christian RetoreAbstract:After a quick overview of the field of study known as "Lexical Semantics", where we advocate the need of accessing additional information besides syntax and Montague-style Semantics at the Lexical level in order to complete the full analysis of an utterance, we summarize the current formulations of a well-known theory of that field. We then propose and justify our own model of the Generative Lexicon Theory, based upon a variation of classical compositional Semantics, and outline its formalization. Additionally, we discuss the theoretical place of informational, knowledge-related data supposed to exist within the lexicon as well as within discourse and other linguistic constructs. The formalization of the structure of natural language utterances around a surface form (phenogrammatics), a deep structure (tectogrammatics) and the meaning thereof as a logical form (Semantics) has developed from the original theories of Curry and Montague to form coherent, type-driven models. Most of these new theories rely upon variations of the compositional analysis of the sentence: from pheno to tectogrammatics, and then to Semantics. Our contribution to this work aims at giving such a model a means to overcome the problems posed by polysemous Lexical units during the semantical analysis of the tectogrammatical form. Building upon an assumed "deep structure", we formalize parts of Pustejovsky's Generative Lexicon Theory, linguistically motivated in Pustejovsky (The generative lexicon, MIT Press, Cambridge, MA, 1995), in a pre-processing of the Semantics of the sentence. The mechanisms of Lexical Semantics we propose are an additional layer of classical Montague compositional Semantics, and, as such, integrate smoothly within such an analysis; we proceed by converting the Lexical data to modifiers of the logical form. This treatment of Lexical Semantics furthermore induces us to think that some sort of non-evident background knowledge of the common use of words is necessary to perform a correct semantic analysis of an utterance. This "commonsense metaphysics" would therefore not be strictly confined to pragmatics, as is often assumed.
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a montague based model of generative Lexical Semantics
Workshop on New Directions in Type-theoretic Grammars (NDTTG 2007), 2007Co-Authors: Bruno Mery, Christian Bassac, Christian RetoreAbstract:Computational Semantics has long relied upon the Montague correspondance between syntax and Semantics, which is not by itself well suited for the computing of some phenomena, such as logical polysemy, addressed by recent advances in Lexical Semantics. Our aim is to integrate the results of Lexical Semantics studies such as the Generative Lexicon Theory in a straightforward way with the existing computing of logical forms, in order to form a Montagovian framework for Lexical Semantics. In addition, we will outline a way to integrate other kinds of semantic information.