Tree-adjoining grammars and lexicalized grammars
نویسندگان
چکیده
In this paper, we will describe a tree generating system called tree-adjoining grammar(TAG)and state some of the recent results about TAGs. The work on TAGS is motivated by linguistic considerations. However, a number of formal results have been established for TAGs, which we believe, would be of interest to researchers in tree grammars and tree automata. After giving a short introduction to TAG, we briefly state these results concerning both the properties of the string sets and tree sets (Section 2). We will also describe the notion of lexicalization of grammars (Section 3) and investigate the relationship of lexicalization to context-free grammars (CFGs) and TAGS (Section 4). Comments University of Pennsylvania Department of Computer and Information Science, Technical Report No. MSCIS-91-22. This technical report is available at ScholarlyCommons: http://repository.upenn.edu/cis_reports/445 Tree-Adjoining Grammars and Lexicalized Grammars MS-CIS-91-22 LINC LAB 197 Aravind K. Joshi Yves Schabes Department of Computer and Information Science School of Engineering and Applied Science University of Pennsylvania Philadelphia, PA 19104-6389
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