Home‎ > ‎

Dick Crouch

Text from old PARC page, gotten from wayback machine in 2007
Richard Crouch

Senior member of research staff
Natural Language Theory and Technology
Information Sciences and Technologies Laboratory (ISTL)
Palo Alto Research Center
3333 Coyote Hill Rd.
Palo Alto, CA 94304
phone: (650) 812-4746
fax: (650) 812-4374
Research Interests
Principal interests in computational semantics and pragmatics, especially ambiguity management, context-dependency, the syntax-semantics interface, and natural language understanding / knowledge representation.

    * Glue Semantics
      The "Glue" approach to semantic interpretation uses a fragment of linear logic to deductively piece together the meanings of words and phrases in parsed sentences. It provides a highly modular syntax-semantics interface that has been applied to a variety of grammatical formalisms (including LFG, HPSG, LTAG, and D-Tree grammar), and to a variety of meaning representations (including higher-order intensional logic, lambda-DRT and UDRT). A glue interpreter has been integrated with the XLE parser. Current activities focus on: development of broad coverage semantic lexicons; robust interpretation in response to ill-formed / out-of-coverage input; further refinements of packed proof-search algorithms for managing syntactic and semantic ambiguity. Intended future work includes implementing context management within glue.

    * Knowledge Extraction from Document Collections
      The XLE and glue semantics is being used as part of a joint project exploring new technologies for analyzing the conceptual content of natural language content in thematically focused document collections. At present, this is concentrating on the use of semantics and inference to detect inconsistent and redundant content in document collections.

    * Other Current Interests
      Metrics for evaluating grammar coverage; summarization; discourse structure; semantics of modals and conditionals.

Brief History
Before joining PARC in December 1998, I was a lecturer (i.e. assistant professor in U.S. terminology) in the Department of Computer Science at Nottingham University, UK. Prior to this I spent a while as a researcher at the Speech Research Unit, DERA Malvern, UK, and over five years at SRI International's Cambridge Computer Science Research Centre. While at SRI I worked on the Core Language Engine, and was also a member of the LRE project Frameworks for Computational Semantics (FraCaS). I have served on the editorial boards of Computational Linguistics and Personal Technologies.
Selected Papers

    * Scalability of redundancy detection in focused document collections. 2002. (Richard Crouch, Cleo Conodoravdi, Reinhard Stolle, Tracy King, Valeria de Paiva, John Everett & Daniel Bobrow) Proceedings of Workshop on Scalability in Natural Language Understanding (ScaNaLU), Heidelberg. [.pdf]

    * Parsing the Wall Street Journal using a lexical-functional grammar and discriminative estimation techniques. 2002. (Stefan Riezler, John Maxwell, Tracy King, Ronald Kaplan, Richard Crouch & Mark Johnson). Proceedings 40th Meeting Association for Computational Linguistics, Philadelphia. [.pdf]

    * A comparison of evaluation metrics for a broad coverage parser. 2002 (Richard Crouch, Ronald Kaplan, Tracy King & Stefan Riezler) Beyond PARSEVAL workshop at 3rd Int. Conference on Language Resources and Evaluation (LREC'02), Las Palmas. [.pdf]

    * Derivational parallelism and ellipsis parallelism. 2002. (Ash Asudeh & Richard Crouch) Proceedings 21st West Coast Conference on Formal Linguistics (WCCFL), Santa Cruz. [draft.pdf]

    * Making ontologies work for resolving redundancies across documents. 2002. (John Everett, Daniel Bobrow, Reinhard Stolle, Richard Crouch, Valeria de Paiva, Cleo Condoravdi, Martin van den Berg, & Livia Polanyi). Communications of the ACM Feb 2002 Vol 45 No. 2, pages 55--60.

    * Counting concepts. 2001. (Cleo Condoravdi, Richard Crouch & Martin van den Berg) Proceedings 13th Amsterdam Colloquium, pages 67-72, Amsterdam. [.pdf]

    * Glue for HPSG. 2001. (Ash Asudeh & Richard Crouch) Proceedings 8th Int. Conference on Head-Driven Phrase Structure Grammar, Trondheim. [.pdf]

    * Preventing Existence. 2001. (Cleo Condoravdi, Richard Crouch, Martin van den Berg, John Everett, Valeria de Paiva, Reinhard Stolle & Daniel Bobrow). Proceedings of Int. Conference on Formal Ontologies in Information Systems, Maine. [.pdf]

    * Linear logic based transfer. 2001. (Richard Crouch, Anette Frank & Josef van Genabith). Proceedings 4th International Workshop on Computational Semantics, Tilburg. Revised version to appear in Bunt & Muskens (eds) Computing Meaning, volume 3, Kluwer. [iwcs.pdf]

    * Glue, Underspecification and Translation. 2001. (Richard Crouch, Anette Frank & Josef van Genabith). 2001. In Bunt, Muskens & Thijsse (eds) Computing Meaning, volume 2, (Studies in Linguistics and Philosophy, 77), Kluwer. Revised version of paper in 3rd International Workshop on Computational Semantics, Tilburg 1999. [iwcs.pdf]

    * Linear Logic for Linguists. 2000. Notes for introductory course given with Josef van Genabith at ESSLLI-00, Birmingham. [.pdf]

    * Context change, underspecification and the structure of glue language derivations.  1999. (Richard Crouch and Josef van Genabith), in Semantics and Syntax in Lexical Functional Grammar: The Resource Logic Approach. (edited by Mary Dalrymple) MIT Press.  [draft.pdf]

    * Dynamic and underspecified semantics for LFG. 1999. (Josef van Genabith and Richard Crouch), in Semantics and Syntax in Lexical Functional Grammar: The Resource Logic Approach. (edited by Mary Dalrymple) MIT Press.  [draft.pdf]

    * Porting a Dynamic Meaning Representation Language into LFG's Linear Logic Based Glue-Language Semantics  1999. (Josef van Genabith and Richard Crouch)  In Bunt, &Muskens (eds) Computing Meaning, volume 1 (Studies in Linguistics and Philosophy, 73), Kluwer. Revised version of paper in Proc. 2nd International Workshop on Computational Semantics, Tilburg, 1997. [iwcs.pdf]

    * Ellipsis and glue lanaguages  1999. (Richard Crouch) in Fragments: Studies in Ellipsis and Gapping (edited by Shalom Lappin and Elabbas Benmamoun) Oxford University Press. [draft.pdf]

    * Interpreting f-structures as UDRSs. 1997.(Josef van Genabith and Richard Crouch) Proc. 35th ACL / 8th European ACL. [.pdf]

    * Direct and underspecified interpretations of LFG. 1996. (Josef van Genabith and Richard Crouch) Proc. COLING-96. [.pdf]

    * Context change and underspecification in glue language semantics.  1996.  (Richard Crouch and Josef van Genabith) Proc. 1st LFG Conference. (Extended and much improved version in Crouch and van Genabith 1999, above.) [.pdf]

    * F-structures, QLFs and UDRSs. 1996. (Josef van Genabith and Richard Crouch) Proc. 1st LFG Conference. [.pdf]

    * Ellipsis and quantification: a substitutional approach.  1995. (Richard Crouch) Proc. 7th EACL. [.pdf]

    * Tense and simple conditionals. 1993. (Richard Crouch) Proc. 9th Amsterdam Colloquium. [.pdf]

    * Time and modality in a natural language interface to a planning system. 1993. (Richard Crouch and Stephen Pulman), Artificial Intelligence 63. pp265-304. 1993. (Reprinted in Pereira and Grosz, eds, Natural Language Processing, MIT Press, 1994)

    * The temporal properties of English conditionals and modals. 1993. PhD thesis, Computer Laboratory, University of Cambridge. [.pdf]

    * Monotonic semantic interpretation. 1992. (Hiyan Alshawi and Richard Crouch) Proc. 30th ACL. 1992. [.pdf]

Teaching Material
At various times I have found myself preparing notes for lecture courses.   Here are some of them, without any guarantees as to their accuracy, usefulness, lack of plagiarism, completeness, or coherence:

    * Formal language theory. (Undergraduate course at Nottingham University) [notes.pdf][slides.pdf]

    * Algorithms and data structures. (Undergraduate course at Nottingham University) [notes.pdf][slides.pdf]

    * Introduction to prolog. (MPhil course at Cambridge University) [slides.pdf]

    * Glue semantics (Slides from NASSLLI-02 course given with Ash Asudeh and Mary Dalrymple). [slides.pdf] See also the homepage of a more extended course given at Stanford.

    * Linear logic & proof theory for linguists. (Course at ESSLLI-00) [notes.pdf][slides.ps]

    * Temporal semantics. (Course at ESSLLI-98) [slides.pdf]

Married to Valeria Paiva, and father of Anna and Eric.