DATR Theories and DATR Models

Bill Keller

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arXiv · cmp-lg/9505004

DATR Theories and DATR Models

Bill Keller

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Abstract

Evans and Gazdar introduced DATR as a simple, non-monotonic language for representing natural language lexicons. Although a number of implementations of DATR exist, the full language has until now lacked an explicit, declarative semantics. This paper rectifies the situation by providing a mathematical semantics for DATR. We present a view of DATR as a language for defining certain kinds of partial functions by cases. The formal model provides a transparent treatment of DATR's notion of global context. It is shown that DATR's default mechanism can be accounted for by interpreting value descriptors as families of values indexed by paths.

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Bill Keller. 1995-05-02. DATR Theories and DATR Models. https://arxiv.org/abs/cmp-lg/9505004

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