Fifteen years ago, a town in Italy experienced a strange type of mass hysteria known as “the 53 fever.” The madness was related to the national lottery.
Who bet on it Game of the lotto, whose operation is similar to that of bingo, they must choose between 11 different wheels, corresponding to cities like Bari, Naples or Venice.
Once they have chosen which reels to play on, they can bet on numbers ranging from 1 to 90.
The winnings depend on how much you bet initially, how many numbers it livedgin and how much is right.
However, sometime in 2003, 53 just left get out at the Venice draws, prompting players to bet more and more on that number, with the certainty that it would soon appear.
In early 2005, the ’53 fever seemed to have led to thousands of people to financial ruin, which resulted in a series of suicides.
The hysteria only disappeared when the number finally showed up in the February 9 draw, after it had been absent in 182 and 4,000 million euros (just under $ 4,700 million) had been bet on it in total.
Although it may sound crazy, the losers had been ruined by a reasoning error called “gambler’s fallacy”.
It is something worryingly common that can lead us to make mistakes in many of our professional decisions, from the response of a soccer goalkeeper during a penalty, to stock market investments and even court rulings on new asylum petition cases.
To find out if you are one of those who would fall for the gambler’s fallacy, imagine that you toss a coin in the air a series of times and you get the following sequence: heads, heads, tails, tails, tails, tails, tails, tails, tails, tails , cross, cross, cross.
How likely are you to get heads on the next release?
Many people believe that, as a matter of probability, the sequence must be leveled and, consequently, it seems inevitable that heads will follow.
But basic probability theory tells us that events are statistically independent.
This means that the odds are exactly the same every time the coin is tossed in the air.
The probability of heads is still 50% even if tails have been rolled 500 or 5,000 times in a row.
For the same reason, HTHTTH is as likely as HHHHHH.
Although many still do not seem like this and they keep thinking that the mixed sequence is somehow more likely that continues.
The gambler’s fallacy has focused the interest of researchers studying gambling.
It is also known as the “Monte Carlo Fallacy”, because in 1913 one of the roulette tables at the Monaco casino recorded 26 blacks in a row.
Researchers who have studied the images captured by security cameras from different casinos confirm that this error continues to affect gamblers today.
Surprisingly, education and intelligence do not protect us against bias.
In fact, a study by Chinese and American researchers found that people with a higher IQ are actually more susceptible to the gambler’s fallacy than those who score lower on standardized tests.
It could be that the smartest people overthink patterns and think they are smart enough to predict what will come next.
Whatever the reason for these false intuitions, several subsequent investigations have revealed that the gambler’s fallacy may have serious consequences beyond the casinos.
That same bias seems to be present in the stock markets, for example.
When there are many short-term changes in the stock price, they are usually essentially random fluctuations.
And Matthias Pelster of the University of Paderborn in Germany has shown that investors often base their decisions on the belief that prices will soon “equalize.”
So, like those who play the lottery in Italy, they bet that the streak will end.
“Investors should buy and sell considering that the streak can continue, but also that it can change,” he says.
“However, that is not what the data tells us.”
The gambler’s fallacy is a problem particularly in those professions that require an impartial judgment, without bias.
A team of researchers recently analyzed the judges’ decisions in the United States regarding asylum applications.
Also the judges
The order of the cases shouldn’t matter, but the investigators found that due to the gambler’s fallacy, there was 5.5% less likely that a judge would grant asylum to an applicant if the previous two had been granted it.
This represents a serious decrease in the average acceptance rate of 29%.
Consciously or not, they seemed to conclude that it was too unlikely to be able to decide the same thing three times in a row, so they were inclined to break the streak.
Next, the researchers analyzed the staff of the banks in charge of studying the loan applications.
Once again, the order of the applications made the difference: there was up to 8% more chance that an application would be rejected after having accepted two or more in a row, and vice versa.
Also in baseball
As a final test, the team analyzed the decisions of umpires at Major League Baseball games.
In this case, there was approximately 1.5% less chance that the referee would declare strike in a launch if the previous one had also been, a small but significant bias that could make a difference in a match.
Kelly Shue, one of the study’s co-authors, says she was initially surprised by the results.
“Because they are professionals and making those decisions is the main thing in their work,” he says.
But still, they were still vulnerable to bias.
Soccer players should pay special attention to the player’s fallacy.
In a penalty shoot-out, it takes the ball between 0.2 and 0.3 seconds to reach the goal.
“The goalkeeper must [por tanto] decide if jump to one side or stay in the center from the goal around the same time the kicker chooses how to take the penalty, “explains Simcha Avugos of Ben-Gurion University in Israel.
This means that the decision for both of you is essentially a bet.
Will they bet like baseball judges, benches and umpires against a streak?
The Avugos team recently analyzed kicking at events such as the FIFA World Cup and Champions League from the UK, and that’s what they found.
Given these results, the team argues that footballers could exploit this trend if they continue firing in the same direction during a shoot penalties.
It may seem that most jobs are far from falling into these high-stakes situations, but Shue believes that the gambler’s fallacy occurs in many other races.
Even when we don’t realize that we are making unconscious probabilistic judgments.
He gives as an example Employee recruitment.
If the interviewers have already seen a good candidate, they may not expect another exceptional individual.
“And then he’s more likely to give the next person a worse grade.”
Intuition about chance
The same is true of teachers who grade their students’ exams, he says.
Similarly, if you are an editor, you could turn down the next JK Rowling based solely on the fact that you recently found other stellar novels to publish.
Whatever your profession, you will do well to remember the “53 fever” in Italy and the chaos it brought.
Occasional streaks can and do occur in any type of sequence.
We would all be more rational if we accept that our intuition about chance is often completely wrong.
David Robson is the author of “The Intelligence Trap: Why Smart People Do Dumb Things,” which examines our most common thinking mistakes and how to correct them.
Now you can receive notifications from BBC Mundo. Download the new version of our app and activate them so you don’t miss out on our best content.