Modeling Informal Debates

Many r u l e s of fo rma l debate are w e l l documented, of common knowledge, and " l ooked -up " in p r e p a r a t i o n f o r planned deba t i ng . I n f o r m a l debates, on the o ther hand, are h i g h l y dynamic, are complex, and are spontaneously generated w i t h no p r i o r r u l e -book p r e p a r a t i o n . They t o o , however, are r u l e g o v e r n e d . In t h i s paper I present an a b s t r a c t process model capable o f model ing " w e l l " formed" argument s t r u c t u r e s t h a t occur i n o r d i n a r y conve rsa t i ons . The f o r m a l i z a t i o n r e s t s on a genera l t heo re t t i ca l framework f o r d iscourse engagement encapsulated in a d isoourse ATN grammar. A major f e a t u r e of the system is i ts segmentat ion o f d isoourse u t te rances in to f u n c t i o n a l l y r e l a t e d oon tex t spaoes. A, I n t r o d u c t i o n A c lose a n a l y s i s of spontaneous conversa t ion revea l s t h a t i t i s h i g h l y ru l e -gove rned , and t h a t i t s u n d e r l y i n g s t r u c t u r e i s a h i e r a r o h i o a l s imu l taneous ly (1 ) accounts f o r many sur faoe l i n g u i s t i c s phenomena found in conve rsa t i ona l speech: (2 ) i d e n t i f i e s the r e l e v a n t d iscourse oon tex t in which subsequent u t te rances are g e n e r a t e d / i n t e r p r e t e d ; (3) exp la i ns the semantic coherent f l o w of a c o n v e r s a t i o n ; and (4) s p e c i f i e s op t i ons a v a i l a b l e t o oonversants a t d i s c r e t e p o i n t s in the d l soou rse . These elements are fundamental in model ing i n f o r m a l debate s t r u c t u r e s . B. The Context Spaoe Theory of Dlsoourse 1. Conversa t iona l moves In the d iscourse theory proposed he re , a conve rsa t i on is seen as a sequence of converzat iona l moves where in each move corresponds to a speaker ' s nnmnnl f i i t i lY f t MSMl v l s a v i s a p a r t i c u l a r m p r e c e d i n g s e c t i o n o f d i scou rse . • S u p p o r t , * "Cha l lenge ,■ and " I n t e r r u p t , " are o f the communicative goa ls I d e n t i f i e d i n t h i s The goa ls are s p e c i f i c to "maxim-abid ing themat io development of a d l soou rse , and do r e f e r t o u n d e r l y i n g speaker emot ive i n t e n t i o n s . A l l c o n v e r s a t i o n a l moves have a s e t of (1 ) p recond i t i ons which s p e o l f l e s the r e q u i s i t e raj