How Do Bookmakers Set the Odds?

NBA Betting Odds Explained

You head over to your favorite betting portal and see the match you’ve been waiting for has finally been listed. You don’t like the odds, so you check another one, and another one. Surprisingly, the odds listed at each of them are almost identical. You start to suspect that they have made secret arrangements – but let me assure you this is not the case. The odds are similar for completely different reason.

Statistics and Probabilities

Bookmakers have vast databases at hand, that contain all the stats of all players and teams, and people (+ algorithms) that know exactly what to do with all the data they have. They calculate the probability of each outcome you can bet on – based not on opinions or feelings, but based on statistics and other factors of influence.

Bookmakers take everything into account, even the unexpected. A team that plays away from home is more likely to lose – that’s an obvious one, but what about the time of the game, the gap since the last game and more. The referee can also influence the outcome, and so can unexpected injuries, penalties, accidents, and even the number of fans cheering at the game. These are all taken into account when calculating the odds the bookie can offer. And they take into account the fact that more punters are likely to bet on the favorite as well. Plus their own profit, since bookmakers are not charities, right?

That’s why the odds you will see on bookmaker comparison site, such as Grizzly sports betting hub,  will be more or less similar.

But, it doesn’t end there….

Why the Odds Change before the Game Starts?

I am sure you’ve noticed that the odds keep on changing all the time, even before the event starts and without any significant news. Obviously, certain facts can and should change the lines, such as Draymond Green suspension in Game #5 of the Finals. But, when there are no news, why they still change?

The answer is simple: they change according to your bets. Not only yours of course, but all the bettors combined. The bookies do not want to “take side” on any bet. Meaning they do not want to bet against you, but just server as a market place where people practically bet against each other through them. So when a significant of bets on a certain outcome are much higher than the opposite, the odds change accordingly to equalize things.

For example: let’s say that the odds on Cavs – Warriors winning Game #7 were +190 vs. -230. Then, the bookmaker (and his algorithms) noticed that there are more bets coming on Cavs win. Few minutes later, you will see the odds on Cavs win getting lower and on the Warriors going in the opposite direction:  +160/-180 or something like that.

These adjustments happen all the time, every second. That way the bets on each side will become more and more equal.

Can we use it to our advantage? We might, a bit. By betting early, when the lines published, you might take advantage of certain “miscalculation” of the odds, before other notice it as well and the odds get adjusted. The downside here is that you leave plenty of time for things to change – player get injured for example, which can turn the whole thing upside down.

What about Tipsters?

If you have enough data, you can predict the most probable outcome of a match more or less precisely. And there are people who have turned this possibility into a quite profitable business, selling their own predictions for the upcoming events. Some of them give out their betting tips free of charge, over the internet. Others – professional tipsters, as they are called – will either charge for their tips on a specific game or offer predictions regularly, for a subscription.

If you are curious about how this works, watch “Two for the Money“. The movie tells the story of Brandon Lang (Matthew McConaughey), a former football player who was forced out of the game by an injury and uses his prediction skills in the world of sports betting. He partners with Walter (Al Pacino), and enters the world of high profile sports betting. Everything’s great until… but I’ll let you discover the rest.

Sports are Predictable

Even if the average sports fan doesn’t have enough information at hand to predict the outcome of a game with the same result as tipsters or bookies, those really into the game can do so with enough precision to become successful punters.