Artificial Intelligence Techniques in Games with Incomplete Information: Opponent Modelling in Texas Hold'em

Games have been widely used as an application for Artificial Intelligence techniques because of their simplicity and well-defined rules but in the other hand, for their huge range of possible and complex strategies to reach the final objective. In the last years, Artificial Intelligence study applied to games has focused more in games with incomplete information and non-deterministic games where players do not have complete information about the entire state of the game and where random events occur throughout the game. The game of Poker is a perfect theme for studying this subject and thus it was selected for this Project. The most known Poker variant is Texas Hold’em that combines simple rules with a huge amount of possible playing strategies. The work is focussed on developing algorithms for “Opponent Modelling” in Texas Hold’em Poker enabling to select the best strategy to play against each given opponent. This opponent modelling capabilities and playing strategy is implemented in an Intelligent Agent capable of observing opponents and adapt his playing mode in function of their behaviour. Several agents were developed in order to simulate typical Poker player’s behaviour and one other agent was developed capable of use opponent modelling techniques in order to select the best playing strategy against each opponent. Experiments were performed using the Texas Hold’em simulator previously developed, in order to verify the capabilities of the Intelligent Agent developed confirming its use of Artificial Intelligence techniques to classify opponents and adapt his game strategy. The tests performed proved that this agent has better results than a regular agent that doesn’t use Opponent Modelling. Although there are still much work to be done in order to obtain an Agent capable to play at human’s level, the work done in this project was positive and could be used as a basis to develop some more sophisticated techniques in the game.