Lucky streaks winning gamblers

Gamblers on winning streaks may seem to win more often, but a study says that’s only because they’re making safer bets. (Image:

Anyone who has ever stepped foot inside a casino – or just made a few friendly bets with friends – has probably run across a streak of incredible good or bad luck at least once. It’s that night where you can’t lose at roulette even if you try, or the one where every coin flip goes against you at the poker table.

For some gamblers, luck and superstition play major roles in their casino routines. Others point out that believing one can predict such good and bad streaks is simply a form of the gambling fallacy, and that there’s no way to know whether random results are about to turn in your favor. But a new study suggests this isn’t exactly true, thanks to the habits of the gamblers themselves.

Winners Keep Winning, Losers More Likely to Lose Again

According to a new study by University College London psychology professor Nigel Harvey and graduate student Juemin Xu, it turns out that winning players do tend to keep winning, while losers are more likely to continue their losing streaks. The study, published in the May 2014 issue of Cognition, looked at online gamblers at a sports betting site to come to these conclusions.

Don’t worry: the study didn’t just rewrite the laws of probability. Instead, it turns out that gamblers tend to engage in behavior that improves the odds that they’ll continue winning (or losing) more often than one might expect.

The study looked at over 565,000 bets made by 776 bettors. On the first bet any customer made, their odds of winning was just 48 percent. A follow-up to that winner would win at a 49 percent rate – a very small increase that hardly seems significant. But after that, the odds went through the roof. After two wins, a third bet would win 57 percent of the time. If the streak kept going, the next bets would win 67 percent of the time, then 72 percent, and finally 75 percent of the time for the sixth bet in a winning streak. Meanwhile, losing players saw their odds plunge as time went on. After a loss, gamblers would only come back to win 47 percent of the time. After two losses, that number dropped to 45 percent, and kept going down – all the way to an astounding 23 percent after six losses.

Betting Behavior Accounts for Change

The numbers are hard to argue with. But if streaks aren’t predictable, what could be causing this? The researchers first looked to see if the players with the winning streaks were simply better at betting than those who had bad runs. But in the end, both groups lost almost exactly the same amount of money per pound they bet. Instead, it turns out that the answer was in the kinds of bets the gamblers were making. Players on winning streaks increasingly turned to safer bets in order to keep their streaks alive.

Meanwhile, losers were trying riskier and riskier bets – either to chase their losses, or perhaps because they felt their luck had to change soon. That behavior was possibly inspired by the gambler’s fallacy: the idea that results will have to change to “balance” a player’s luck. However, it actually served to increase the likelihood that the streaks would continue.

Essentially, the “hot hand” fallacy (the belief that hot streaks will continue, or the opposite of the gambler’s fallacy) was found to be true, but only because players were actively helping their streaks to last longer than they would if they made similar bets regardless of their recent results. It’s not new math – it’s just another way in which human behavior can cause some unexpected results.