Field Testing the Transformational Question Answering (Tqa) System

The T r a n s f o r m a t l o n a l q u e s t i o n Answer ing (TqA) sys tem was deve loped ove r a p e r i o d o f t i m e b e g i n n i n g in t h e e a r l y p a r t o f t h e l a s t decade and c o n t i n u i n g t o t h e p r e s e n t . I t s s y n t a c t i c component i s a t r a n s f o r m a t i o n a l grammar p a r s e r [ 1 , 2, ~ ] , and i t s s e m a n t i c Gomponqnt i s a Knu th a t t r i b u t e grammor [~ , 5 ] . The c o m b i n a t i o n o f these components providQs sufficiQnt generality, conveniQnga, and efficiency to implement a broad range of linguistic models; in addition to a wide spectrum of t r a n s f o r m a t i o n a l grammars, G i l d e r t y p e ph rase s t r u c t u r e grammar [ 6 ] and l e x i g a l f u n c t i o n a l grammar [ 7 ] sys tems appear t o be cases in p o i n t , f o r example . The P a r t i c u l a r grammar Nh ich was, in f a c t , d e v e l o p e d , however , was c l o s e s t tO t h o s e o f t h e g e n Q r a t i v e s e m a n t i c s v a r i e t y o f t r s n s f o r m a t i o n e l grammar; bo th t he u n d e r l y i n g s t r u c t u r e s a s s i g n e d t o sQntences and t h e t r a n s f o r m a t i o n s employed t o e f f e c t t h a t ass ignmQnt t r a c e d t h e i r o r i g i n s t o t h e g e n e r a t i v e s e m a n t i c s model .