# Vacant Spaces vs the House Edge

## Is There a Crossover Between a Bridge Player & a Sports Bettor?

At first glance, this question will garner mixed opinions. Perhaps for the more ardent sports bettors among us, the answer is yes. For those who are involved in sports betting on a more social level, the answer is more than likely a no. Below, we examine the crossovers between playing Bridge, and betting on sports – focusing on the probability front.

In the game of Bridge, mathematics plays a key role in determining the outcome of the game. Different players will use different strategies to work their way through a game, and each will have a varying degree of success. The Theory of Vacant Spaces, for example, is a widely used probability counter in Bridge – it’s a simple metric to gauge the location of a card in the hands that have been dealt. The theory can be applied to any combinations of cards  to estimate the probable split.

Sports betting is similarly a game of probabilities. When a bookmaker is offering even money, or 1/1, for an outcome – they’re effectively saying that the probability of that event coming true is one in every two occasions, or 50:50. Likewise, a 5/1 shot is the bookies way of indicating that for every six times a race is run, that particular selection would win on one occasion.

However, the difference lies in the house edge. Whereas Bridge is played out between two players, teamed up in two groups of two – aside from betting exchanges, sports betting is the punter versus the house. And with this, brings the house edge. This is where we can begin to look at implied probability – converting a sportsbook price into a simple percentage, but taking into account the house edge.

We just need to look at the ‘to win the toss’ market in a tennis game. Whether Andy Murray or Novak Djokovic wins the toss is a complete 50:50 shot, which implies that odds should be even money, or 1:1. However, because the sports bettor is punting against the house, the latter takes a small margin and thus offers a price of 10/11 on either outcome. This price implies that there is a 46% probability of either event occurring, meaning the house is taking an 8% margin.

So, while both bridge and sports betting require an element of mathematics and statistical analysis to be successful, both are used in different ways. Bridge is a true statistical analysis based on the theory of vacant places, whereas sports betting is an implied probability – with odds offered being less than the true chance of that selection winning. This is one of a number of reasons why sportsbooks will offer various bonus codes and such like to attract new customers in – because the law of averages ensures that they take a profit on every market, with everything else being equal, due to their margins.

Playing Bridge online doesn’t offer this type of incentive, because all four players know that they have a fair and true statistical chance of winning.

Bridge and sports betting are very similar in many ways, but for the more risk adverse and keener mathematician amongst us – Bridge is certainly the game for you.