4.6 Hobbyists

Several programs by hobbyists were examined to explore the architecture and approach used. The most common approach is expert-based, however simulation-based approaches tend to be stronger (although more computationally expensive).

• xbot by Greg Reynolds uses an expert system which is manually patched when weakness is observed.

  http://webusers.anet-stl.com/~gregr/

• replicat by Stephen How also uses an expert system in combination with observing a large number of possible features about the hand and board ( e.g. three-straight).

• r00lbot by Greg Wohletz is perhaps the strongest of the three IRC programs. For the pre-flop it uses Sklansky and Malmuth's recommendations [14], and for the post-flop it conducts a series of simulations (playing out the hand to the showdown, typically 3,000 times) against N random hands (where N is the number of opponents, and is artificially adjusted for bets and raises). The actual action is dependent on what percentage of simulations resulted in a win.

• Smoke'em Poker is a Five-Card Draw program by Dave O'Brien. It uses an expert system and has a set of rules for each opponent type ( e.g. tight, loose).

  http://www.cgl.uwaterloo.ca/~gmgrimsh/poker.html

• There are two poker games by Johann Ruegg, Sozobon Ltd. Both the Seven-Card Stud and Texas Hold'em games use a simulation-based approach where the program plays the hand to the showdown several times against random opponents. The resulting winning percentage is artificially adjusted depending on the game state and compared against several hard-coded action thresholds.

  ftp://ftp.csua.berkeley.edu/pub/rec.gambling/poker/spoker.tar.Z