Comparative Study of Approximate Strategies for Playing Sum Games Based on Subgame Types

Abstract

Combinatorial games of the form {{A|B}|{C|D}} can be classified as either left excitable, right excitable, or equitable [2]. Several approximate strategies for playing sums of games of this form have been proposed in the literature [2,3,4]. In this work we propose a new approach for evaluating the different strategies based on the types of the subgames participating in a sum game. While previous comparisons [3,4] were only able to rank the strategies according to their average performance in a large number of randomly generated games, our evaluation is able to pinpoint the strengths and weaknesses of each strategy. We show that none of the strategies can be considered the best in an absolute sense. Therefore we recommend the development of type-based approximate strategies with enhanced performance.