Many people mistakenly believe that rules of conditional probability can give a player insight into the results of the next spin – for example, if red has been the result for the previous 5 spins, a sense of logic may lead the player into assuming odds are high that black will come up next. The is a FAILED assumption that many casinos encourage by providing charts and pens to track previous rolls, online casinos often offer lists of previous spins so players can hedge their bets ‘wisely’. Many people are fooled into thinking this is an effective strategy by reasoning with the law of averages – stating that the probability of any number will equalize in the long run – so a number that has shown favour over the night has a decreasing probability of being landed on again every time it’s played. This is a FALSE understanding of laws of probability. In reality, each spin of the roulette wheel is an Independent event – in probability terms, that means that the out come of each spin is unrelated to any previous outcomes. Each number is as likely to come up as any other, on every spin, regardless of the frequency of which that number has previously been selected.
In European, or single “0″ roulette the house has an advantage of 2.7% calculated by the formula (35-36)/37 x 100 = 2.7%.
As a rule of thumb in roulette – expect to lose the value of your average stake per bet over 37 games. There are 37 possible outcomes with each spin – with zero holding the house advantage. So, if you play £20 a spin and the odds are exact, by the 37th spin you will be at a £20 loss. In other words, for every £37 you bet, you will end up with £36. However, the odds are rarely exact and will always rise and fall, with a slightly stronger pull towards the fall – because of the house’s advantage.
Some guidelines, however can help you have a successful run at the roulette table despite the house’s advantage. The hardest to follow, but the most important, is to leave while you are ahead. In the long run, the house will always win, so leaving will the odds have favored you may be hard after the excitement of winning, but its the surest way of keeping a profit at the end of the night.
Safe bets to play are outside bets – evens/odds, colors, high/low; these bets cut the banks advantage – even if the spin lands on “0″, you’ll get half your loss back. Another safe bet: take a look at the table, and notice how its divided into three length-wise sections, all 2:1 bets (1-34, 2-35, 3-36). Notice that the row with numbers 3 to 36 has 8 red numbers and only 4 black? Playing an outside red bet, along with a bet on the 3-36 column would cover a large portion of the board, as well as give a high return if red is rolled.
Use the following chart to see what the odds of each bet is, compared to the amount paid out:
