Craps systems
Martingale system
No betting system can consistently beat casino games of pure chance such as craps, but that does not stop hopeful gamblers believing in them. One of the best known systems is the Martingale in which the player starts by betting $1 and doubles his bet whenever he loses. Upon winning, he starts over at $1. The idea is to realize a net win of $1 after every eventual win. This system fails because the player will either run out of money after having to double his bet several times in a row after a streak of losing bets, or he will be unable to bet the amount dictated by the system because it would exceed the maximum bet allowed by the casino.
Gambler's fallacy
Other systems depend on the gambler's fallacy, which in craps terms is the belief that past dice rolls influence the probabilities of future dice rolls. For example, the gambler's fallacy indicates that a craps player should bet on eleven if an eleven has not appeared or has appeared too often in the last 20 rolls.
In reality, each roll of the dice is an independent event, so the probability of rolling an eleven is exactly 1/18 on every roll, even if eleven has not come up in the last 100 rolls, or if eleven has come up 5 times in the last 5 rolls. The common term to describe this is "dice have no memory".
Parity hedge system
The parity hedge system is a hoax promulgated by Quatloos. Despite the fact that no such system exists (indeed, it is a mathematical impossibility), several gambling-related web sites have retold the 'parity hedge' story without attribution.
Dice setting or dice control
Another approach is to "set" the dice in a particular orientation, and then throw them in such a manner that they do not tumble randomly. The theory is that the dice will be more likely to show certain numbers. Unlike other systems, this one is mathematically plausible, because if it were possible to alter the probabilities of each outcome, then winning systems could be devised.
Casinos do take steps to prevent this. The dice are required to hit the back wall of the table, which makes controlled spins more difficult. Whether it is possible for human beings to consistently exercise the precise physical control necessitated by the theory is a source of controversy. A small but dedicated community of controlled shooters maintain records and claim proof of dice influencing in casino conditions. Frank Scoblete, Stanford Wong and Jerry L. Patterson, authors of books that feature dice control techniques, believe that it is possible to alter the odds in the player's favor by dice control.
Chris Pawlicki, a mechanical engineer who (under the pseudonym "Sharpshooter") wrote a book on dice setting called Get The Edge At Craps: How to Control the Dice as a part of the Frank Scoblete "Get the Edge Guides," defined the math and science behind dice control.
In addition, some people offer to teach dice-setting skills for a substantial fee. Currently there has been no independent conclusive evidence that such methods can be successfully applied in a real casino.
