Tree-Adjoining Grammars Are Not Closed Under Strong Lexicalization
نویسندگان
چکیده
A lexicalized tree-adjoining grammar is a tree-adjoining grammar where each elementary tree contains some overt lexical item. Such grammars are being used to give lexical accounts of syntactic phenomena, where an elementary tree defines the domain of locality of the syntactic and semantic dependencies of its lexical items. It has been claimed in the literature that for every tree-adjoining grammar, one can construct a strongly equivalent lexicalized version. We show that such a procedure does not exist: Tree-adjoining grammars are not closed under strong lexicalization.
منابع مشابه
Strong Lexicalization of Tree Adjoining Grammars
Recently, it was shown (KUHLMANN, SATTA: Tree-adjoining grammars are not closed under strong lexicalization. Comput. Linguist., 2012) that finitely ambiguous tree adjoining grammars cannot be transformed into a normal form (preserving the generated tree language), in which each production contains a lexical symbol. A more powerful model, the simple context-free tree grammar, admits such a norma...
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ورودعنوان ژورنال:
- Computational Linguistics
دوره 38 شماره
صفحات -
تاریخ انتشار 2012