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The combination of these components providQs sufficiQnt generality, conveniQnga, and efficiency to implement a broad range of linguistic models; in addition to a wide spectrum of transformational grammars, Gilder-type phrase structure grammar [ 6 ] and l e x i g a l functional grammar . | PỊELD TESTING THE TRANSFORMATIONAL QUESTION ANSWERING TQA SYSTEM s. R. Petrick IBM T.J. Watson Research Center PO Box 218 Yorktown Heights New York 10598 The Transformational Question Answering TQA system was developed over a period of time beginning in the early part of the last decade and continuing to the present. Its syntactic component is a transformational grammar parser 11 2 33 and its semantic component is a Knuth attribute grammar 4 51. The combination of these components provides sufficient generality convenience and efficiency to implement a broad range of Linguistic models in addition to a wide spectrum of transformational grammars Gazdar-type phrase structure grammar 61 and lexical functional grammar 171 systems appear to be cases in point for example. The particular grammar which was in fact developed however was closest to those of the generative semantics variety of transformational grammar both the underlying structures assigned to sentences and the transformations employed to effect that assignment traced their origins to the generative semantics model. The system works by finding the underlying structures corresponding to English queries through the use of the transformational parsing facility. Those underlying structures are then translated to logical forms in a domain relational calculus by the Knuth attribute grammar component. Evaluation of logical forms with respect to a given data base completes the question-answering process. Our first logical form evaluator took the form of a toy implementation of a relational data base system in LISP. We soon replaced the low level tuple retrieval facilities of this implementation with the RS5 Relational storage System portion of the IBM System R 18 . This version of logical form evaluation was the one employed in the field testing to be described. In a more recent version of the system however it has been replaced by a translation of logical forms first to equivalent logical forms in a set domain .
