Incremental Parsing: Bringing Engineering and Cognition Together

Workshop at ACL-2004
Barcelona, Spain, July 25, 2004



Workshop Topic

Much recent parsing research has focused on the limited task of achieving broad coverage and high accuracy in parsing Treebank corpora. The parsing models developed for this task typically work on a sentence-by-sentence basis: they often only deliver a valid analysis if the input consists of a complete sentence. They are not designed to operate incrementally, i.e., to deliver partial analyses (perhaps with associated probabilities) that can be updated on a word-by-word basis as more of the input becomes available.

Incrementality is desirable for two reasons. First, incremental processing is crucial for many NLP tasks. Language modeling, for instance, typically requires that probabilities are assigned incrementally as more and more of the speech stream becomes available. Recently, a number of parsing models have been proposed that have this property and thus can be used for language modeling. These models have resulted in lower perplexity scores and word error rates than the standard n-gram models. However, the parsing accuracy of these models typically falls short of the state of the art. The challenge for parsing research is to develop models that achieve optimal performance for both parsing and language modeling.

The second argument for incrementality comes from cognitive modeling. There is substantial evidence showing that humans process language in an incremental fashion. Any cognitively plausible model of human parsing must take incrementality into account, and the modeling literature contains considerable discussion on the relevant computational mechanisms. Recently, a number of models of human parsing have been proposed that are based on computational linguistic approaches, such as PCFGs and related statistical models, suggesting a potential synergy between cognitively and technologically motivated parsing research.

Target Audience

The aim of the workshop is to address the dual challenge of defining incremental parsing models that are useful for engineering tasks such as language modeling, while also contributing to our understanding and modeling of the human parsing mechanism. The workshop will bring together parsing researchers from the computational linguistics and cognitive modeling communities, and we expect extensive cross-fertilization from this interaction. From the computational linguistic perspective, cognitive modeling presents new challenges for parsing research, including new evaluation measures that go beyond traditional parseval measures. On the other hand, computational linguistics can contribute crucial methodological advances to cognitive modeling. For instance, the application of probabilistic parsing algorithms to cognitive tasks has important implications for the recent debate on the role of frequency information in human parsing.

Areas of Interest

Possible topics for workshop submissions include:

Workshop Organizers

Frank Keller, University of Edinburgh
Stephen Clark, University of Edinburgh
Matthew Crocker, Saarland University
Mark Steedman, University of Edinburgh

Keynote Speakers

Brian Roark, Oregon Graduate Institute, Oregon Health and Science University
Patrick Sturt, Department of Psychology, University of Glasgow

Program Committee

Steve Abney, University of Michigan
Thorsten Brants, Google
Eugene Charniak, Brown University
Ciprian Chelba, Microsoft Research
Michael Collins, MIT
Jeffrey Elman, UCSD
Ted Gibson, MIT
John Hale, Michigan State University
Mark Johnson, Brown University
Gerard Kempen, University of Leiden
Oliver Lemon, University of Edinburgh
Massimo Poesio, University of Essex
Stefan Riezler, Palo Alto Research Center
Brian Roark, Oregon Health and Science University
Douglas Roland, UCSD
Ed Stabler, UCLA
Suzanne Stevenson, University of Toronto
Patrick Sturt, University of Glasgow

Contact Information

The organizers can be contacted at:
School of Informatics
University of Edinburgh
2 Buccleuch Place
Edinburgh EH8 9LW, UK
phone: +44-131-650-4407
fax:   +44-131-650-4587
email: acl04_workshop@inf.ed.ac.uk


created 2004-01-05, last modified 2004-06-05