Fingerprints: enabling visualization and automatic analysis of strategies for two player games

Evolutionary computation can create a vast number of strategies for playing simple games. Analysis of these strategies is typically more time-consuming than their production. As a result, analysis of strategies produced by an EC system is often lacking or restricted to the extraction of superficial summary statistics. This study presents a technique for extracting a functional signature from evolved agents. This signature can be used as a visualization of agent behavior in games with two moves and also provides a numerical target for clustering and other forms of automatic analysis. The fingerprint can be used to induce a similarity metric on the space of game playing agents. This study develops fingerprints in the context of the iterated prisoner´s dilemma but they can be computed for any two player simultaneous game with a finite set of moves.