2006 AAAI Computer Poker Competition

Michael Littman

Rutgers University

Martin ZinkevichChristian Smith

Luke DuguidU of Alberta

What is Poker?

• The OR View– A partial information game with over 1018

states.

• The AI View– A huge opponent modeling challenge.

• The Public View– Really popular! Lots of fun!

What is the Game?

• Play 1000 hands of Heads-up Limit Texas Hold’em Poker against an opponent

• Reset bots, switch seats, and play again with the same hands.– lower variance– more fair

• Repeat 6-20 times– Can treat the outcome of the duplicate match as a

random variable which we have sampled several times.

How do you win?

• Make money!• Bankroll Competition

– Against overall, have the maximum total bankroll

– Highlights opponent modeling and learning

• Series Competition– Against individuals, have positive bankroll– Highlights the OR problem of “solving” the

game

The Teams

• Hyperborean: University of Alberta Edmonton, Canada

• Bluffbot: Finland

• Monash: Monash University, Australia

• Teddy: USA

• Gs2: Carnegie Mellon University, Pittsburgh, USA

Before I Begin

• There is a period that is allocated for competitors to contest the results that has yet to expire.

Bankroll Results

Competitor Winnings

(small bets/hand)

Teddy

(USA)

-0.4616 sb/h

Bankroll Results

Competitor Winnings

(small bets/hand)

Monash

(Monash U., Australia)

-0.0273 sb/h

Teddy

(USA)

-0.4616 sb/h

Bankroll Results

Competitor Winnings

(small bets/hand)

Bluffbot

(Finland)

0.0954 sb/h

Monash

(Monash U., Australia)

-0.0273 sb/h

Teddy

(USA)

-0.4616 sb/h

Bankroll Results

Competitor Winnings

(small bets/hand)

Hyperborean

(U. Alberta)

0.3935 sb/h

Bluffbot

(Finland)

0.0954 sb/h

Monash

(Monash U., Australia)

-0.0273 sb/h

Teddy

(USA)

-0.4616 sb/h

Bankroll-Heads Up

Hyperborean

(U Alberta)

Bluffbot

(Finland)

Monash

(Monash U)

Teddy

(USA)

Hyperborean

(U Alberta)

Hyperborean

Wins

Hyperborean

Wins

Hyperborean Wins

Bluffbot

(Finland)

Hyperborean

Wins

Bluffbot Wins Teddy Wins

Monash

(Monash U)

Hyperborean

Wins

Bluffbot Wins Monash Wins

Teddy

(USA)

Hyperborean

Wins

Teddy Wins Monash Wins

Bankroll-Heads Up (Small Bets/Hand)

Hyperborean

(U Alberta)

Bluffbot

(Finland)

Monash

(Monash U)

Teddy

(USA)

Hyperborean

(U Alberta)

0.0514

±0.0171

0.7227

±0.0161

0.4067

±0.0247

Bluffbot

(Finland)

-0.0514

±0.0171

0.5271

±0.0197

-0.1895

±0.0289

Monash

(Monash U)

-0.7227

±0.0161

-0.5271

±0.0197

1.1678

±0.0427

Teddy

(USA)

-0.4067

±0.0247

0.1895

±0.0289

-1.1678

± 0.0427

Bankroll-Overall Significance

• Difference between Bluffbot and U of Alberta

• 0.2982 small bets/hand

• 0.0190 standard deviations

The Most Interesting Result

• In the bankroll competition, in head-to-head, BluffBot beat Monash who beat Teddy who beat BluffBot

• A practical example of the non-transitivity of poker

Results-Series (Small Bets/Hand)

Hyperborean

(U Alberta)

Bluffbot

(Finland)

Gs2

(CMU)

Monash

(Monash U)

Hyperborean

(U Alberta)

Winner:

Hyperborean

Winner:

Hyperborean

Winner:

Hyperborean

Bluffbot

(Finland)

Winner:

Hyperborean

Winner:

Bluffbot

Winner:

Bluffbot

Gs2

(CMU)

Winner:

Hyperborean

Winner:

Bluffbot

Winner:

Gs2

Monash

(Monash U)

Winner:

Hyperborean

Winner:

Bluffbot

Winner:

Gs2

Results-Series (Small Bets/Hand)

Hyperborean

(U Alberta)

Bluffbot

(Finland)

Gs2

(CMU)

Monash

(Monash U)

Hyperborean

(U Alberta)

0.1145

±0.0375

0.1843

±0.0079

0.7344

±0.029

Bluffbot

(Finland)

-0.1145

±0.0375

0.1200

±0.0561

0.5214

±0.0408

Gs2

(CMU)

-0.1843

±0.0079

-0.1200

±0.0561

0.6512

±0.0397

Monash

(Monash U)

-0.7344

±0.029

-0.5214

±0.0398

-0.6512

±0.0398

Things to Never Assume

• All bots will work on the competition machines the first time

• The server code is bug-free

• Everybody has a common idea of the rules of poker (or even heads-up Texas Hold’em)

• People can write code instantaneously

Exhibitionary Aspects of the Competition

• Bots submitted late

• Bots debugged after the deadline

• The time limit was very large for the series competition

Maybe Next Year

• More advance notice• Competitors need access to one of the

machines they will use• Server code needs to be frozen before the

competition begins• More variants of poker need to be included,

especially:– >2 players– >1000 hands

• There has to be a 7 sec/hand time limit

Is Poker “Solved”?

• No one has ever solved a four-round abstraction of poker without a partition into the early game and the late game.

• The game of poker is also about your opponent. For instance, playing rock-paper-scissors against a four-year-old is different than against an adult.

Next Year

• This summer: write the rules

• This winter: write the code

• Next summer: next competition

Are You Interested?

• Come talk to us

• maz@cs.ualberta.ca

• bowling@cs.ualberta.ca

Summary

• The poker competition brought together five teams in two competitions.

• The competition was very close, and very interesting, non-transitive (A beats B beats C beats A) performance was observed.

• A freeware codebase was developed for future competitions.