Modeling Contract Bridge Bid Opening Strategies using the aspps System
Deborah East · 2006
Abstract Contract bridge is a popular and complex cardgame which has two distinct phases: the auction(bidding) and play. The result of the bidding is acontract (the number of tricks to be taken duringplayandthetrumpsuit). Success dependsas muchonthecontractasontheplay. Thedifculty inbid-ding has resulted in the development of strategiesfor bidding. In this paper, we model the openingstrategiesbasedonvariationsofprecisionandStan-dardAmerican.The language of logic PS + is used for encodingdata and dening the rules for the bridge open-ing program. We take advantage of the nonmono-tonic properties of the language of logic PS + tomodelcontractbridgeopenings. The aspps systemconsists of two modules: psgrnd (for groundinga problem denition with the data of an instanceof the problem) and the aspps solver. We showthatthe aspps systemgeneratesanswerŒsetsforourbridge opening program where each answerŒset isanopeningbid. 1 Introduction Contract bridge is a popular and complex card game whichhas two distinct phases: the auction (bidding) and play. Theresult of the bidding is a contract (the number of tricks to betaken during play and the trump suit). Success depends asmuch on the contract as on the play. A contract is reachedby cooperation between partners where a dialog is limitedto bids. During bidding each player can only see his ownhand (13 cards) thus a player must draw inferences from hisbids of his partnerand to a lesser degreefrom the bids of hisopponents. The difculty in bidding has resulted in the de-velopment of strategies for bidding. In this paper, we modelthe opening strategies based on variations of precision [Wei,1996]andStandardAmerican[DowneyandPomer,2004].The language of logic PS