How to Understand Probability

July 27, 2017

Understanding the probability of an outcome in a football match or in any other branch of betting can be of paramount importance for success.

The probability behind a game of football and a tennis match is not the same, understandably, but once you determine whether the events you are trying to determine the probability behind are independent, conditional or mutually exclusive, calculating their probability should as simple as one, two, three.

What does Probability Mean?

Probability is basically the likelihood of a random event happening and is often expressed as a ratio or fraction.

Probability deals with events that are hard to predict such is the case in sports betting when you determine the chance of an outcome occurring by dividing the number of favourable outcomes with a number of possible outcomes.

When it comes to betting on football, the probability of a favourable outcome occurring depends on multiple aspects related to the match itself, participants or circumstances around it. The mathematical probability of an outcome occurring – with football betting where you have three possible outcomes – revolves around 33%, but it rarely stands evenly distributed mostly because of the aspects that influence the outcome.

In order to understand the football – or better said – sports-related probability, one must acknowledge the existence of the implied probability, which plays a crucial role in betting.

What is Implied Probability?

Implied probability in sports betting is a conversion of traditional odds into a percentage while taking into account the bookmakers’ edge and then eliminating it in order to show true odds of an event happening.

Bookmakers’ determination of a probability behind any outcome occurring will rarely represent the true probability of an outcome, mostly because of the house edge. Should there be no advantage in their favour, they would quickly run out of business but shrewd punters will find a way to get past them and find value even when probability is seemingly working against them.

Converting implied probability into odds – decimal or fractional – gives you a chance to compare the probability determined and probability given by a bookmaker.

Implied Probability = 1/Decimal Odds and the odds of 1.65 on Liverpool against Watford translate into 0.606 which stands for 60.6% implied probability percentage.

When it comes to fractional odds as a reflection of the return you will receive for a particular amount bet, the implied probability stands as – denominator / (denominator + numerator). With 5/2 on Bournemouth to surprise Arsenal at the Emirates, the implied probability stands as this:

5/2 = 2 / (2+5) = 2 / 7 = 0.2857 = 28.57% which tells us that betting on Bournemouth in this particular case would not be a wise choice.

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