Multiple Context-Free Tree Grammars and Multi-component Tree Adjoining Grammars
نویسندگان
چکیده
Strong lexicalization is the process of turning a grammar generating trees into an equivalent one, in which all rules contain a terminal leaf. It is known that tree adjoining grammars cannot be strongly lexicalized, whereas the more powerful simple context-free tree grammars can. It is demonstrated that multiple simple context-free tree grammars are as expressive as multi-component tree adjoining grammars and that both allow strong lexicalization.
منابع مشابه
Multiple Context-Free Tree Grammars: Lexicalization and Characterization
Multiple (simple) context-free tree grammars are investigated, where “simple” means “linear and nondeleting”. Every multiple context-free tree grammar that is finitely ambiguous can be lexicalized; i.e., it can be transformed into an equivalent one (generating the same tree language) in which each rule of the grammar contains a lexical symbol. Due to this transformation, the rank of the nonterm...
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