D’Alembert System

This is another system widely used and was invented by a French mathematician in the 1900’s. This system is fairly simple but probably would not be too successful if play on a double zero wheel. If however you a playing on a single zero wheel with the “en prison” or “le partage” rule then you may stand a chance of ending your day at the casino ahead.

The premise behind this system is when two different events have an equal chance of happening as one starts occurring more often than the other the alternative event must begin to occur more often in order to achieve equilibrium. You can see this happen yourself if you toss a coin and record the results. If you toss a few times say 20 there is a very high likelyhood you will get a considerable difference the percentage of heads thrown and tails. The more you toss it the less the percentage difference between these amounts tends to get. If you were to toss them an infinite amount of times you will get 50% heads and 50% tails. You can test this at home. The problem with this premise is that the roulette table is not a 50/50 outcome there are the extra zero or zeros to factor in.

The system is very simple you start with a set bet lets say £5 and you every time you win you decrease your bet by one and every time you lose you increase it by one. For example

Amount Bet Win/Lose Amount Won/Lost
5 lose -5
6 win +1
5 lose -4
6 win +2
5 lose -3
6 win +3

The trouble is if you win five times in a row you reach the table minimum and the system falls down. You raise your starting amount to counter this you will run into the same problems as with the Martingale system. You will be risking large sums of money trying to win very little.