Inessential Features
نویسنده
چکیده
If one converts surface lters into context free rules, one has to introduce new features. These features are strictly nonlexical, and their distribution is predictable from the distribution of the lexical features. Now, given a (feature based) context free grammar, we ask whether one can identify the nonlexical features. This is not possible; however, the notion of an inessential feature ooers an approximation. To arrive at a descriptive theory of language one needs to eliminate all the inessential features. One can measure the complexity of a language by the complexity of the formulae needed to deene the distribution of inessential features.
منابع مشابه
Inessential Features, Ineliminable Features, and Modal Logics for Model Theoretic Syntax
While monadic second-order logic (MSO) has played a prominent role in model theoretic syntax, modal logics have been used in this context since its inception. When comparing propositional dynamic logic (PDL) to MSO over trees, Kracht (1997) noted that there are tree languages that can be defined in MSO that can only be defined in PDL by adding new features whose distribution is predictable. He ...
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