While we've delved into this topic previously (here), the NCAA basketball tournaments' "championship weekend" provides an opportune time to update the Tversky et al. paper, Misconceptions of Chance Processes in Basketball (1985). To refresh, one of the co-authors recently summarized the paper's key insight.
GILOVICH: "Well, everyone who’s ever played the game of basketball knows you get this feeling where the game seems to slow down. It becomes easier, or you almost don’t even have to aim that carefully. The ball’s going to go in. It’s one of the most compelling feelings that you can have. And it turns out if you statistically analyze people’s shots — whether it’s professional games, college basketball players shooting in a gym, although the feeling exists when you make several shots in a row — you will feel hot. That feeling very surprisingly doesn’t predict how you’re going to do in the next shot or the next several shots — the distribution of hits and misses in the game of basketball looks just like the distribution of heads and tails when you’re flipping a coin. although of course, not every player shoots 50%. Very few of them do."
Not surprisingly, the "hot hand" thesis attracted scrutiny. Gelman's take on the thesis is quite clear: "That’s wrong. The distribution of hits and misses in the game of basketball does not look just like the distribution of heads and tails when you’re flipping a coin." Gelman's criticism echos a 2015 paper (revised in 2016), Surprised by the Gambler's and Hot Hand Fallacies? A Truth in the Law of Small Numbers, by Miller and Sanjurjo, where the authors find:
"... a subtle but substantial bias in a standard measure of the conditional dependence of present outcomes on streaks of past outcomes in sequential data. The mechanism is driven by a form of selection bias, which leads to an underestimate of the true conditional probability of a given outcome when conditioning on prior outcomes of the same kind. The biased measure has been used prominently in the literature that investigates incorrect beliefs in sequential decision making — most notably the Gambler’s Fallacy and the Hot Hand Fallacy. Upon correcting for the bias, the conclusions of some prominent studies in the literature are reversed."
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