Poker And Calculating Odds

Introduction

One of the basic skills of poker that you need to get to grips with, if you really are serious about winning money rather than just playing poker socially, is that of calculating poker odds. Poker odds are mathematical calculations of odds or probabilities – and mastering them will give you an advantage over opponents who rely on their luck and instinct to know how to play a particular hand or round of betting.

What are the probabilities?

Want to make serious money from poker - then start calculating those odds.

Want to make serious money from poker - then start calculating those odds.

The theory of probability is over three hundred years old and was first formulated by the Frenchmen Fermat and Pascal. In the simplest of terms possible, they realized that you could actually calculate the chance of a particular outcome occurring after rolling a dice. If you just have one dice then you have a 1 in 6 (1:6) chance of rolling a six, or indeed any other number, which is quite straight forward. However, what is the probability (chance if you will) of rolling a double six if you had say two dice? You could be forgiven for thinking the probability of throwing at least one double six with two dice is still 1:6 or that it might be a maximum of 1:12. Unfortunately the law of mathematics and probability doesn’t work that way; and the chances of throwing a six with two dice actually goes out to 1:36. The calculation, as established by Fermat and Pascal all those years ago, is 1/6 x 1/6 = 1/36, as there are 36 possible outcomes from throwing two dice, only one of which is double six.

Increasing the probability of an event occurring

Wonder what the poker chances are with her?

Wonder what the poker chances are with her?

Before proceeding to talk about poker cards and probability we need to add a couple of comments following on from the previous section, which has importance to how you view probabilities in poker games. If rolling two dice you stand a 1:36 chance of hitting double six – how many double sixes will you hit in 36,000 throws of the dice? This is where probability theory gets interesting – in 36,000 rolls you can expect 1000 double sixes. So, and we hope you’re paying attention now, the more you repeat a play in poker – the more likely you are to hit a winner! Also, before we get too deep into poker probabilities; being good with figures helps – but you don’t need to be a math genius to work things out at the poker table. A tip here is to know that the probability of something occurring and the probability of it not occurring will always add up to 1. So, if you have a 1:10 (1/10 or 0.1) chance of picking up a winning card – you also have a 9:10 (9/10 or 0.9) chance of not doing so. So a 1:10 chance might not actually be that good a chance at all.

Applying probabilities to poker

What is the probability of getting two hole aces?

What is the probability of getting two hole aces?

In poker, unlike in say craps and rolling dices, we need to deal with the probability of several events occurring one after the other. To work out these probabilities you simply multiply the likelihood of one probability occurring by the next one and so on. Let’s look at that with a simple example, suppose you have a deck of 52 cards and want to know what the chances are of you dealing yourself two aces straight off. The probability (chance) of the first card being an ace is 4 in 52 (4/52 – four aces in a 52 card deck), that leaves three aces in 51 cards, meaning you now have a 3 in 51 (3/51) chance of dealing another ace. The odds on you dealing two consecutive aces, as if they were hole cards in a poker game, here would be 4/52 x 3/51, which gives you odds of 1:222 (0.45%). So, in a real game of poker with other players at the poker table – your odds will change as they too will all be being dealt cards.

What do you think?

So, you’re sitting on the dealers left at a four seat poker table. You’ll be first to be dealt a card, in a game of Texas Hold ‘em what are your chances of being dealt two pocket aces? 4/52 x 3/51 giving 1 in 222 or 4/52 x 3/48 giving 1 in 208; or something completely different? What do you think and then let us know.