d'Alembert Roulette Strategy
The d'Alembert system is very simple and relatively thrifty. It bears the name of the French mathematician, physicist and philosopher Jean le Rond d'Alembert (1717–1783).
Principle of the System
The principle of the d'Alembert strategy consists in betting on red or black numbers. Again it could be possible to bet on any other even odds (high/low, even/odd numbers) with the same payout ratio of 1:1.
Firstly you bet one unit (1$, 10$, ...) on your favourite colour. If you win in the first spin, then the "sequel" ends and you start all over with one unit. If you lose, you will bet an extra unit in the next round. If you win, your next bet will be lower than your last bet by one unit. It means that if you are successful you win a higher bet, if you are unlucky, you lose a lower amount.
| Bet Amount | Outcome of the Bet | Profit/Loss | Cumulated Profit/Loss | Next Bet (Loss +1, Win -1) |
|---|---|---|---|---|
| 1 unit | loss | -1 | -1 | +1 |
| 2 units | loss | -2 | -3 | +1 |
| 3 units | loss | -3 | -6 | +1 |
| 4 units | win | 8 | +2 | -1 |
| 3 units | win | 6 | +8 | -1 |
| 2 units | loss | -2 | +6 | +1 |
| 3 units | win | 6 | +12 | -1 |
| 2 units | win | 4 | +16 | -1 |
| 1 unit | win | 2 | +18 | The sequel ends, start over with 1 unit. |
The Evaluation of the d'Alembert Strategy
The system is very profitable if you catch a good sequel. Of course the opposite situation can occur. Netherless the betting system of d'Alembert is very economical, so it is very unlikely and unlucky to ruin your capital quickly – what could happen if you used e.g. the Martingale strategy, when your bets are doubled after each lost spin.