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Essay, Parsing Combinatory Categorial Grammar via Planning in Answer Set Programming, from Correct reasoning: essays on logic-based AI in honour of Vladimir Lifschitz, co-authored by Yuliya Lierler, UNO faculty member. Combinatory categorial grammar (CCG) is a grammar formalism used for natural language parsing. CCG assigns structured lexical categories to words and uses a small set of combinatory rules to combine these categories to parse a sentence. In this work we propose and implement a new approach to CCG parsing that relies on a prominent knowledge representation formalism, answer set programming (ASP) - a declarative programming paradigm. We formulate the task of CCG parsing as a planning problem and use an ASP computational tool to compute solutions that correspond to valid parses. Compared to other approaches, there is no need to implement a specific parsing algorithm using such a declarative method. Our approach aims at producing all semantically distinct parse trees for a given sentence. From this goal, normalization and efficiency issues arise, and we deal with them by combining and extending existing strategies. We have implemented a CCG parsing tool kit - AspCcgTk - that uses ASP as its main computational means. The C&C supertagger maybe used as a preprocessor within AspCcgTk that allows us to achieve wide-coverage natural language parsing.
Publication Date
1-1-2012
Publisher
Springer
Keywords
computers, technology, artificial intelligence, programming languages, logic
Disciplines
Computer Sciences
Recommended Citation
Yu. Lierler and P. Schueller, Parsing Combinatory Categorial Grammar via Planning in Answer Set Programming, Correct Reasoning: Essays on Logic-Based AI in Honour of Vladimir Lifschitz (Lecture Notes in Computer Science / Theoretical Computer Science and General Issues), Springer, 2012