Lexical semantics

Papers

2010

Jianguo Li and Chris Brew (2010) A "Class-based Approach to Disambiguating Levin Verbs" Journal of Natural Language Engineering, Special Issue on Distributional Lexical Semantics

2009

Timothy Weale; Chris Brew; Eric Fosler-Lussier (2009) Using the Wiktionary Graph Structure for Synonym Detection; ACL Workshop on Collaboratively Constructed Semantic Resources, Singapore

Kirk Baker and Chris Brew (2009) Multilingual Animacy Classification by Sparse Logistic Regression, Ohio State University Working Papers in Linguistics

2008

Baker, Kirk and Chris Brew (2008) Statistical Identification of English Loanwords in Korean Using Automatically Generated Training Data, The Sixth International Conference on Language Resources and Evaluation (LREC 2008). Marrakech, Morocco. May 28-30, 2008.

Li, Jianguo Kirk Baker and Chris Brew (2008). A Corpus Study of Levin's Verb Classification. American Association for Corpus Linguistics (AACL 2008). Provo, Utah. March 13-15, 2008.

Li, Jianguo & Chris Brew (2008). Which are the Best Features for Automatic Verb Classification. In Proceedings of the 46th Annual Meeting of the Association for Computational Linguistics. Columbus, Ohio, June 2008.

2007

Li, Jianguo and Chris Brew. (2007) Disambiguating Levin Verbs without Using Hand-tagged Data Recent Advances in Natural Language Processing September 27-29, 2007, Borovets, Bulgaria

2006

Li, Jianguo and Chris Brew. (2006) Parsing and Subcategorization Data In Proceedings of the COLING/ACL 2006,515–522 Sydney, Australia

2005

Li, Jianguo, Chris Brew and Eric Fosler-Lussier 2005 Robust Extraction of Subcategorization Data from Spoken Language International Workshop on Parsing Technologies Vancouver, Canada

Li, Jianguo and Chris Brew. (2005) Automatic extraction of subcategorisation frames from spoken corpora In Katrin Erk,Alissa Melinger and Sabine Schulte im Walde Interdisciplinary Workshop on the Identification and Representation of Verb Features and Verb Classes Saarland University, Germany

2004

Lapata, Mirella and Chris Brew (2004) Verb Class Disambiguation using Informative Priors Computational Linguistics: (3)0:1, 45-73

2002

Brew, Chris and Sabine Schulte im Walde. (2002). Spectral Clustering for German Verbs. In Haji ˇc and Matsumoto Proceedings of the 7th Conference on Empirical Methods in Natural Language Processing, Philadelphia, PA., pages 117–124.

Schulte im Walde, Sabine and Chris Brew. (2002). Inducing German Semantic Verb Classes from Purely Syntactic Subcategorisation Information. In ACL Proceedings of the 40th Annual Meeting of the Association for Computational Linguistics, Philadelphia., pages 223–230.

1999

Lapata, Maria and Chris Brew. (1999). Using subcategorization to resolve verb class ambiguity. In Pascale Fung and Joe Zhou, editors, Joint SIGDAT Conference on Empirical Methods in NLP and Very Large Corpora, pages 397–404, College Park, MD

1998

Poesio, Massimo, Sabine Schulte im Walde, and Chris Brew. (1998). Lexical clustering and definite description interpretation. In J.Choi and N.Green, editors, AAAI Spring Symposium on Learning for Discourse Interpretation, pages 82–89, Stanford, March. American Association for Artificial Intelligence.

Ph.D Theses

    1. Tim Weale (DoD, Fort Meade)
      1. Term Relatedness from Wiki-Based Resources Using Sourced PageRank
      2. This dissertation concerns itself with creating a new algorithm for automatically measuring the amount of relatedness between a given pair of terms. Research into term relatedness is important because it has been empirically demonstrated that using relatedness metrics can improve the performance of tasks in Natural Language Processing and Information Retrieval by expanding the usable vocabulary. Previous relatedness metrics have used a variety of sources of semantic data to judge term relatedness, including text corpora, expertly-constructed resources and, most recently, Wikipedia and Wiktionary. The primary focus of this dissertation is the creation of a new metric for deriving term relatedness from the graph structure of Wikipedia and Wiktionary using Sourced PageRank, a modified version of the PageRank algorithm, to generate the relatedness values.
    2. Kirk Baker (iCubed analytics)
      1. MULTILINGUAL DISTRIBUTIONAL LEXICAL SIMILARITY
      2. This dissertation addresses the problem of learning an accurate and scalable lexical classifier in the absence of large amounts of hand-labeled training data. One approach to this problem involves using a rule-based system to generate large amounts of data that serve as training examples for a secondary lexical classifier. The viability of this approach is demonstrated for the task of automatically identifying English loanwords in Korean. A set of rules describing changes English words undergo when they are borrowed into Korean is used to generate training data for an etymological classification task. Although the quality of the rule-based output is low, on a sufficient scale it is reliable enough to train a classifier that is robust to the deficiencies of the original rule-based output and reaches a level of performance that has previously been obtained only with access to substantial hand-labeled training data. The second approach to the problem of obtaining labeled training data uses the output of a statistical parser to automatically generate lexical-syntactic co-occurrence features. These features are used to partition English verbs into lexical semantic classes, producing results on a substantially larger scale than any previously reported and yielding new insights into the properties of verbs that are responsible for their lexical categorization. The work here is geared towards automatically extending the coverage of verb classification schemes such as Levin, VerbNet, and FrameNet to other verbs that occur in a large text corpus.
    3. Jianguo Li, Motorola
      1. HYBRID METHODS FOR ACQUISITION OF LEXICAL INFORMATION: THE CASE FOR VERBS
      2. Improved automatic text understanding requires detailed linguistic information about the words that comprise the text. Particularly crucial is the knowledge about predicates, typically verbs, which communicate both the event being expressed and how participants are related to the event. ... First, deriving Levin-style verb classifications from text corpora helps avoid the expensive hand-coding of such information, but appropriate features must be identified and demonstrated to be effective. One of our primary goals is to assess the linguistic conditions which are crucial for lexical classification of verbs. In particular, we experiment with different ways of mixing syntactic and lexical information for improved verb classification. Second, Levin verb classification provides a systematic account of verb polysemy. We propose a class-based method for disambiguating Levin verbs using only untagged data. The basic working hypothesis is that verbs in the same Levin class tend to share their subcategorization patterns as well as neighboring words. In practice, information about unambiguous verbs in a particular Levin class is employed to disambiguate the ambiguous ones in the same class. Last, automatically created verb classifications are likely to deviate from manually crafted ones, therefore it is of great importance to understand whether automatically created verb classifications can benefit the wider NLP community. We propose to integrate verb class information, automatically learned from text corpora, into a particular parsing task, PP-attachment disambiguation.
        1. Sabine Schulte im Walde Stuttgart
          1. Experiments on the Automatic Induction of German Semantic Verb Classes
            1. This thesis investigates the potential and the limits of an automatic acquisition of semantic classes for German verbs. Semantic verb classes are an artificial construct of natural language which generalises over verbs according to their semantic properties; the class labels refer to the common semantic properties of the verbs in a class at a general conceptual level, and the idiosyncratic lexical semantic properties of the verbs are either added to the class description or left underspecified. Examples for conceptual structures are `Position' verbs such as `liegen' (to lie), `sitzen' (to sit),`stehen' (to stand). On the one hand, verb classes reduce redundancy in verb descriptions, since they encode the common properties of verbs. On the other hand, verb classes can predict and refine properties of a verb that received insufficient empirical evidence, with reference to verbs in the same class; under this aspect, a verb classification is especially useful for the pervasive problem of data sparseness in NLP, where little or no knowledge is provided for rare events. To my knowledge, no German verb classification is available for NLP applications. Such a classification would therefore provide a principled basis for filling a gap in available lexical knowledge.
            1. ...
            2. The automatic induction of the German verb classes is performed by the k-Means algorithm, a standard unsupervised clustering technique as proposed by Forgy (1965). The algorithm uses the syntactico-semantic descriptions of the verbs as empirical verb properties and learns to induce a semantic classification from this input data. The clustering outcome cannot be a perfect semantic verb classification, since (i) the meaning-behaviour relationship on which we rely for the clustering is not perfect, and (ii) the clustering method is not perfect for the ambiguous verb data. But the goal of this thesis is not necessarily to obtain the optimal clustering result, but to understand the potential and the restrictions of the natural language clustering approach. Only in this way we can develop a methodology which can be applied to large-scale data. Key issues of the clustering methodology refer to linguistic aspects on the one hand, and to technical aspects on the other hand.
        1. Mirella Lapata (Faculty, Informatics, Edinburgh)
        2. The Acquisition and Modeling of Lexical Knowledge: A Corpus-based Investigation of Systematic Polysemy.
        3. This thesis deals with the acquisition and probabilistic modeling of lexical knowledge. A considerable body of work in lexical semantics concentrates on describing and representing systematic polysemy, i.e., the regular and predictable meaning alternations certain classes of words are subject to. Although the prevalence of the phenomenon has been long recognized, systematic empirical studies of regular polysemy are largely absent, both with respect to the acquisition of systematic polysemous lexical units and the disambiguation of their meaning.
        4. The present thesis addresses both tasks. First, we use insights from linguistic theory to guide and structure the acquisition of systematically polysemous units from domain independent wide-coverage text. Second, we constrain ambiguity by developing a probabilistic framework which provides a ranking on the range of meanings for systematically polysemous words in the absence of discourse context.
        5. We focus on meaning alternations with syntactic effects and exploit the correspondence between meaning and syntax to inform the acquisition process. The acquired information is useful for empirically testing and validating linguistic generalizations, extending their coverage and quantifying the degree to which they are productive. We acquire lexical semantic information automatically using partial parsing and a heuristic approach which exploits fixed correspondences between surface syntactic cues and lexical meaning. We demonstrate the generality of our proposal by applying it to verbs and their complements, adjective-noun combinations, and noun-noun compounds. For each phenomenon we rely on insights from linguistic theory: for verbs we exploit Levin's (1993) influential classification of verbs on the basis of their meaning and syntactic behavior; for compound nouns we make use of Levi's (1978) classification of semantic relations, and finally we look at Vendler's (1968) and Pustejovsky' (1995) generalizations about adjectival meaning.
        6. We present a simple probabilistic model that uses the acquired distributions to select the dominant meaning from a set of meanings arising from syntactically related word combinations. Default meaning --the dominant meaning of polysemous words in the absence of explicit contextual information to the contrary-- is modeled probabilistically in a Bayesian framework which combines observed linguistic dependencies (in the form of conditional probabilities) with linguistic generalizations (in the form of prior probabilities derived from classifications such as Levin's (1993)). Our studies explore a range of model properties: (a) its generality, (b) the representation of the phenomenon under consideration (i.e., the choice of the model variables), (c) the simplification of its parameter space through independence assumptions, and (d) the estimation of the model parameters. Our findings show that the model is general enough to account for different types of lexical units (verbs and their complements, adjective-noun combinations, and noun-noun compounds) under varying assumptions about data requirements (sufficient versus sparse data) and meaning representations (corpus internal or corpus external).