Dependency Grammar and Dependency Parsing

Despite a long and venerable tradition in descriptive linguistics, dependency grammar has until recently played a fairly marginal role both in theoretical linguistics and in natural language processing. The increasing interest in dependency-based representations in natural language parsing in recent years appears to be motivated both by the potential usefulness of bilexical relations in disambiguation and by the gains in efficiency that result from the more constrained parsing problem for these representations. In this paper, we will review the state of the art in dependency-based parsing, starting with the theoretical foundations of dependency grammar and moving on to consider both grammar-driven and data-driven methods for dependency parsing. We will limit our attention to systems for dependency parsing in a narrow sense, i.e. systems where the analysis assigned to an input sentence takes the form of a dependency structure. This means that we will not discuss systems that exploit dependency relations for the construction of another type of representation, such as the head-driven parsing models of Collins (1997, 1999). Moreover, we will restrict ourselves to systems for full parsing, which means that we will not deal with systems that produce a partial or underspecified representation of dependency structure, such as Constraint Grammar parsers (Karlsson, 1990; Karlsson et al., 1995).