REQUIREMENTS FOR A WORLDCLASS
- By Sam Jack
- Published 05/27/2008
Sam Jack
Try your lucky Although formally endorsed by everyone, the tips below are held as 'common knowledge' by many players and represent solid general strategy for the long-run.
We have identified several key components that address
some of the required activities of a strong poker player.
However, these components are not independent. They
must be continually refined as new capabilities are added
to the program.
Hand strength assesses the strength of a hand in relation
to the other hands. The simplest hand strength
computation is a function of the cards in the hand and the
current community cards. A better hand strength
computation takes into account the number of players still
in the game, the position of the player at the table, and the
history of betting for the current game. An even more
accurate calculation considers the probabilities for each
possible opponent hand, based on the likelihood of each
hand being played to the current point in the game.
Hand potential computes the probability that a hand will
improve to win, or that a leading hand will lose, as
additional community cards appear. For example, a hand
that contains four cards in the same suit may have a low
hand strength, but has good potential to win with a flush
as more community cards are dealt. Conversely, a hand
with a high pair could decrease in strength and lose to a
flush as many cards of a common suit appear on the
board. At a minimum, hand potential is a function of the
cards in the hand and the current community cards.
However, a better calculation could use all of the
additional factors described in the hand strength
computation.
Betting strategy determines whether to fold, call/check,
or bet/raise in any given situation. A minimum strategy is
based on hand strength. Refinements consider hand
potential, pot odds (your winning chances compared to the
expected return from the pot), bluffing, opponent
modeling and trying to play unpredictably.
Bluffing allows you to make a profit from weak hands,2
and can be used to create a false impression about your
play to improve the profitability of subsequent hands.
Bluffing is essential for successful play. Game theory can
be used to compute a theoretically optimal bluffing
frequency in certain situations. A minimal bluffing system
merely bluffs this percentage of hands indiscriminately. In
practice, you should also consider other factors (such as
hand potential) and be able to predict the probability that
your opponent will fold in order to identify profitable
bluffing opportunities.
Unpredictability makes it difficult for opponents to form
an accurate model of your strategy. By varying your
playing strategy over time, opponents may be induced to
make mistakes based on an incorrect model.
Opponent modeling allows you to determine a likely
probability distribution for your opponent’s hidden cards.
A minimal opponent model might use a single model for
all opponents in a given hand. Opponent modeling may be
improved by modifying those probabilities based on the
collected statistics and betting history of each opponent.
There are several other identifiable characteristics that
may not be necessary to play reasonably strong poker, but
may eventually be required for world-class play.
Opponent modeling is integral to successful poker play.
Koller and Pfeffer have proposed a system for
constructing a game-theoretic optimal player [13].
However, it is important to differentiate an optimal
strategy from a maximizing strategy. The optimal player
makes its decisions based on game-theoretic probabilities,
without regard to specific context. The maximizing player
takes into account the opponent’s sub-optimal tendencies
and adjusts its play to exploit these weaknesses.
In poker, a player that detects and adjusts to opponent
weaknesses will win more than a player who does not. For
example, against a strong conservative player, it would be
correct to fold the probable second-best hand. However,
against a weaker player who bluffs too much, it would be
an error to fold that same hand. In real poker it is very
common for opponents to play sub-optimally. A player
who fails to detect and exploit these weaknesses will not
win as much as a better player who does. Thus, a
maximizing program will out-perform an optimal program
against sub-optimal players.
Although a game-theoretic optimal solution for Hold’em
would be interesting and provide a good baseline for
comparing program (and human) performance, it would in
no way “solve the game.” To produce a world-class poker
program, strong opponent modeling is essential.
some of the required activities of a strong poker player.
However, these components are not independent. They
must be continually refined as new capabilities are added
to the program.
Hand strength assesses the strength of a hand in relation
to the other hands. The simplest hand strength
computation is a function of the cards in the hand and the
current community cards. A better hand strength
computation takes into account the number of players still
in the game, the position of the player at the table, and the
history of betting for the current game. An even more
accurate calculation considers the probabilities for each
possible opponent hand, based on the likelihood of each
hand being played to the current point in the game.
Hand potential computes the probability that a hand will
improve to win, or that a leading hand will lose, as
additional community cards appear. For example, a hand
that contains four cards in the same suit may have a low
hand strength, but has good potential to win with a flush
as more community cards are dealt. Conversely, a hand
with a high pair could decrease in strength and lose to a
flush as many cards of a common suit appear on the
board. At a minimum, hand potential is a function of the
cards in the hand and the current community cards.
However, a better calculation could use all of the
additional factors described in the hand strength
computation.
Betting strategy determines whether to fold, call/check,
or bet/raise in any given situation. A minimum strategy is
based on hand strength. Refinements consider hand
potential, pot odds (your winning chances compared to the
expected return from the pot), bluffing, opponent
modeling and trying to play unpredictably.
Bluffing allows you to make a profit from weak hands,2
and can be used to create a false impression about your
play to improve the profitability of subsequent hands.
Bluffing is essential for successful play. Game theory can
be used to compute a theoretically optimal bluffing
frequency in certain situations. A minimal bluffing system
merely bluffs this percentage of hands indiscriminately. In
practice, you should also consider other factors (such as
hand potential) and be able to predict the probability that
your opponent will fold in order to identify profitable
bluffing opportunities.
Unpredictability makes it difficult for opponents to form
an accurate model of your strategy. By varying your
playing strategy over time, opponents may be induced to
make mistakes based on an incorrect model.
Opponent modeling allows you to determine a likely
probability distribution for your opponent’s hidden cards.
A minimal opponent model might use a single model for
all opponents in a given hand. Opponent modeling may be
improved by modifying those probabilities based on the
collected statistics and betting history of each opponent.
There are several other identifiable characteristics that
may not be necessary to play reasonably strong poker, but
may eventually be required for world-class play.
Opponent modeling is integral to successful poker play.
Koller and Pfeffer have proposed a system for
constructing a game-theoretic optimal player [13].
However, it is important to differentiate an optimal
strategy from a maximizing strategy. The optimal player
makes its decisions based on game-theoretic probabilities,
without regard to specific context. The maximizing player
takes into account the opponent’s sub-optimal tendencies
and adjusts its play to exploit these weaknesses.
In poker, a player that detects and adjusts to opponent
weaknesses will win more than a player who does not. For
example, against a strong conservative player, it would be
correct to fold the probable second-best hand. However,
against a weaker player who bluffs too much, it would be
an error to fold that same hand. In real poker it is very
common for opponents to play sub-optimally. A player
who fails to detect and exploit these weaknesses will not
win as much as a better player who does. Thus, a
maximizing program will out-perform an optimal program
against sub-optimal players.
Although a game-theoretic optimal solution for Hold’em
would be interesting and provide a good baseline for
comparing program (and human) performance, it would in
no way “solve the game.” To produce a world-class poker
program, strong opponent modeling is essential.
