W. Detmar Meurers

A Web-based Instructional Platform for Contraint-Based Grammar Formalisms and Parsing

We propose the creation of a web-based training framework comprising a set of topics that revolve around the use of feature structures as the core data structure in linguistic theory, its formal foundations, and its use in syntactic processing.

On Expressing Lexical Generalizations in HPSG

This paper investigates the status of the lexicon and the possibilities for expressing lexical generalizations in the paradigm of Head-Driven Phrase Structure Grammar (HPSG). We illustrate that the architecture readily supports the use of implicational principles to express generalizations over a class of word objects. A second kind of lexical generalizations expressing relations between classes of words is often expressed in terms of lexical rules. We show how lexical rules can be integrated into the formal setup for HPSG developed by King (1989, 1994), investigate a lexical rule specification language allowing the linguist to only specify those properties which are supposed to differ between the related classes, and define how this lexical rule specification language is interpreted. We thereby provide a formalization of lexical rules as used in HPSG.

Detecting Errors in Discontinuous Structural Annotation

Consistency of corpus annotation is an essential property for the many uses of annotated corpora in computational and theoretical linguistics. While some research addresses the detection of inconsistencies in positional annotation (e.g., part-of-speech) and continuous structural annotation (e.g., syntactic constituency), no approach has yet been developed for automatically detecting annotation errors in discontinuous structural annotation. This is significant since the annotation of potentially discontinuous stretches of material is increasingly relevant, from tree-banks for free-word order languages to semantic and discourse annotation.In this paper we discuss how the variation n-gram error detection approach (Dickinson and Meurers, 2003a) can be extended to discontinuous structural annotation. We exemplify the approach by showing how it successfully detects errors in the syntactic annotation of the German TIGER corpus (Brants et al., 2002).

A grammar formalism and parser for linearization-based HPSG

Linearization-based HPSG theories are widely used for analyzing languages with relatively free constituent order. This paper introduces the Generalized ID/LP (GIDLP) grammar format, which supports a direct encoding of such theories, and discusses key aspects of a parser that makes use of the dominance, precedence, and linearization domain information explicitly encoded in this grammar format. We show that GIDLP grammars avoid the explosion in the number of rules required under a traditional phrase structure analysis of free constituent order. As a result, GIDLP grammars support more modular and compact grammar encodings and require fewer edges in parsing.

Advancing linguistics between the extremes: Some thoughts on Geoffrey R. Sampson's “Grammar without grammaticality”

Abstract The ready availability of large corpora has opened a range of interesting possibilities for linguistic research, and Geoffrey Sampsons article illustrates that a corpus-based perspective can also motivate revisiting the general direction and methodology of linguistic research. At the same time, the discussion in Sampsons article pushes two issues to rather extreme conclusions, which I think could be useful to revisit here.

``Language and Computers'': Creating an Introduction for a General Undergraduate Audience

This paper describes the creation of Language and Computers, a new course at the Ohio State University designed to be a broad overview of topics in computational linguistics, focusing on applications which have the most immediate relevance to students. This course satisfies the mathematical and logical analysis requirement at Ohio State by using natural language systems to motivate students to exercise and develop a range of basic skills in formal and computational analysis. In this paper we discuss the design of the course, focusing on the success we have had in offering it, as well as some of the difficulties we have faced.