Saturday, July 27, 2013

"The Science of Winning Poker"

From the Wall Street Journal:

Bluffing still matters, but the best players now depend on math theory
More than 6,300 players, each paying an entry fee of $10,000, gathered in Las Vegas early this month for the championship event of the 44th annual World Series of Poker. The tournament ran for 10 days, and just nine players now remain. They will reunite in November for a two-day live telecast to determine who wins the first prize: $8.3 million.

Poker didn't get this big overnight. In 2003, a then-record 839 players entered the championship for a shot at $2.5 million. The winner was an amateur with the improbable name of Chris Moneymaker. After ESPN devoted seven prime-time hours to his triumph, online poker took off and tournament participation ballooned, as did prize pools. The U.S. government's ban on the major online poker sites in 2011 reined in enthusiasm, but the game has continued to grow in Europe, Asia and Latin America.

This growth over the past decade has been accompanied by a profound change in how the game is played. Concepts from the branch of mathematics known as game theory have inspired new ideas in poker strategy and new advice for ordinary players. Poker is still a game of reading people, but grasping the significance of their tics and twitches isn't nearly as important as being able to profile their playing styles and understand what their bets mean.

In no-limit hold'em poker, the game used for the World Series championship, each player is dealt two private cards and attempts to make the best five-card hand that he can by combining his own cards with five cards that are shown faceup and shared by all players. Those cards are revealed in stages: The first three are the "flop," the fourth is the "turn," and the fifth is the "river." Players can bet any amount they like at each stage.
Suppose you hold a pair of sevens, and before the flop is dealt you go all-in (bet all of your chips). One player calls your bet, and everyone else folds their hands. You both turn your cards face up, and you are happy to see your opponent show a pair of sixes. You are in great shape, since you have the better hand. But when the flop arrives, it contains a six, giving your opponent three sixes, and your own hand doesn't improve, so you lose. Was your all-in play correct?

In terms of results, it wasn't, because you lost all your chips. But according to the math of hold'em, a pair of sevens is favored to beat a pair of sixes 81% of the time. So if you can go all-in with sevens and get your bet called by players holding sixes over and over again, luck should even out, and eventually you will be a big winner.

Poker theorist David Sklansky once wrote that you should consider yourself a winner as long as you had the higher probability of winning the hand when all the money went into the pot. This attitude is consistent with the underlying mathematical reality of poker, and it can smooth out your emotional reactions to losses and wins. What matters is the quality of your decisions, not the results that come from them....MORE