The Thomas Donald betting system is quite widespread among gamblers. It is also based on the principle of increasing a bet by one unit after a lost spin and decreasing it after a win. The author of the system puts forward the following requirements.
- Firstly, your bankroll should be at least three thousand initial bets. Thus, if you bet one dollar, you should have three thousand dollars. This system is first and foremost designed to make even money bets, although at brick and mortar casinos such small bets on them are not usually observed. It is up to you to select the size of your bankroll.
- Secondly, the Thomas Donald believed that the total number of wins and losses over the long run was equal, so that this system gave the profit in the long run. Do not expect instant results from it. Moreover, every time when you visit a casino, you should have enough free time. You can hardly argue with the fact that red and black will come up approximately equal number of times during one year, but deviations are more than possible during a week or month.
If zero comes up, you should increase your bet by one unit, since even money bets always lose when zero appears.
Thomas Donald also insisted that it was prohibited to wager other people's money or borrow it. However this point is irrelevant to the system and is not related to the mathematical calculations. It rather emphasizes the psychological and moral aspects that are important for the successful gameplay.
Donald-Nathanson Betting System
The Thomas Donald betting system was studied by the famous mathematician Lev Nathanson. As a result of his own calculations and observations, he offered its modifications. In particular, he was not satisfied with the paragraphs of the system that determined the gameplay while winning the first bet. In other words, if you bet one dollar and win, it is necessary to leave your bet unchanged in accordance with the Donald system.
Nathanson came to the conclusion that it was necessary to miss one spin. If the same color comes up again (for example, red), you need to treat it as -1. Then you should bet on black. If red appears again, the score is -2, and you should bet two dollars on black.
As for zero, Nathanson offered to increase a positive bet as soon as it comes up and decrease a negative bet.
As for the other rules for the Thomas Donald system, Lev Nathanson agrees with them.
Numerous estimates of its effectiveness showed positive but quite insignificant results. Therefore, it is difficult to say whether it is worth spending so much time in order to win several initial bets or not. The difference between a minimum and maximum is usually insignificant at the high-limit tables, which does not allow using this system.