%A Karl Branting %A Bruce Porter %T Rules and Precedents as
Complementary Warrants %J AAAI-91 %P 3-9 %D 1991 %I AAAI/MIT
Press %X This paper describes a model of the complementarity of
rules and precedents in the classification task. Under this
model, precedents assist rule-based reasoning by
operationalizing abstract rule antecedents. Conversely, rules
assist case-based reasoning through case elaboration, the
process of inferring case facts in order to increase the
similarity between cases, and term reformulation, the process of
relacing a term whose precedents only weakly match a case with
terms whose precedents strongly match the case. Fully exploiting
this complementarity requires a control strategy characterized
by impartiality, the absence of arbitrary ordering restrictions
on the use of rules and precedents. An impartial control
startegy was implemented in GREBE in the domain of Texas
worker's compensation law. In a preliminary evaluation, GREBE's
performance was found to be as good or slightly better