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Property Theory (PT)


When a question is successfully parsed, the parser build a semantic representation of its meaning, using annotations on the grammar rules and lexical items. The initial representation is as a Property-theoretic term. The representation produced by Squirrel is an ASCII approximation to the mathematical symbols that are typically used.

The Squirrel output:

some(a,`manager:a and`for:a:`work:fva1)+
would typically be written as:

The term is a free variable that arises from the semantics of questions. Its name provides some typing information that can be of use later when ruling-out inappropriate interpretations. In this case, we know that the free variable can range only over animate objects. If it were , then it can only range over inanimate objects.

Chris Fox, September 1995