An Introduction to Sports Betting and Odds

This is a short article on sports betting that discusses the difference between the probability of winning and the odds a bookmaker offers.

Proponents of sports betting see it is a recreational activity for sports fans that augments interest in sporting events, this in turn benefits the leagues, teams and players through higher attendances, sponsorship deals and television audiences.

Opponents say it detracts from the honesty of sports because betting on sports changes the nature of true competition, by turning the need to win for pleasure in to winning for profit.

Which ever stance you take on this it is safe to say that as long as sports is with us, so will sports betting.

For the many people who have never placed a bet on a sports match before the whole process can be quite daunting. The numbers, statistics, form terminology is, at first, confusing so much so I simply can not cover it all here but I will walk you through the one key characteristic of betting — Odds.

A very import point to understand is that Odds are not to be confused with Probability, as they are slightly different. The best way to run through this is use an example.

The Probability that Manchester United will win the 2007/08 premiership is “1 in 20” (20 teams in the Premiership and only one winner) and this is expressed as 1/20.

Probability therefore reflects the chances of winning. Now what are Manchester United’s Odds of winning?

They would be “19 to 1”. That’s because odds are actually a ratio of the chances of losing to the chances of winning. Manchester United has a 19 in 20 chance of losing and a 1 in 20 chance of winning. To calculate this ratio you need to take 19/20 over 1/20 and the 20s cancel, leaving us with 19 in 1, which expressed as odds is “19 to 1” or 19/1.

This example of course assumes every team in the premiership has equal probability of winning and this as we know is not the case.

This may seem a little confusing at first but the key thing for you to remember is the Odds bookmakers offer are for what they are willing to pay and NOT the Probability that the event will occur.

There’s an abundance of online sports betting resources and explainations of odds and probability and I have listed some starting points for you here:

Sports betting and odds is a complex topic, and I hope this article has introduced you to the concept. I can only advise you to bet within your budget and if you’re unsure of what you’re betting on — don’t do it!

All the best,

Ps. Drop in and feel free to ask any questions on the MatesOdds blog.

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  1. chris 20 September, 2007
  2. Ahmed Bilal 20 September, 2007
  3. Steve 20 September, 2007
  4. squaretan 22 September, 2007
  5. Steve 22 September, 2007