To test this notion, Gilovich and his team created an experiment to test the hypothesis that if a player is subject to random periods of "hot" and "cold" shooting, he or she should be more likely to make a shot after making his previous one—or previous several—than after missing. So they gathered the shooting records from the 1980-1981 season of the Philadelphia 76ers (then the only team that kept records of the order of a player's hits and misses), and what they found was that
Contrary to the hot hand hypothesis, players were not more likely to make a basket after making their last shot. In fact, there was a slight tendency for players to shoot better after missing their last shot. They made 51 percent of their shots after making their previous shot, compared to 54 percent after missing it. They also had a better chance of making a basket if they missed their previous two or three shots.
But when they interviewed that year's team members, including the famous Julius "Dr. J" Erving, they were firmly convinced otherwise—as were... well, most people, according to Gilovich. They suggested that a "hot" player cools off because opposing players start to guard him more aggressively, or because he gets over-confident and starts taking tougher shots. So Gilovich, now a professor of psychology at Cornell, also studied the players' free-throw records. He found that, on average, they made 75 percent of their second free throws after making their first, and 75 percent after missing their first. In other words, the "streak" leading up to each free throw made no difference whatsoever on the outcome of the shot.
So why does the idea persist? According to Gilovich, it's all in the interpretation.
Research psychologists have discovered that people have faulty intuitions about what chance sequences look like. People expect sequences of coin flips, for example, to alternate between heads and tails more than they actually do. Because chance produces less alternation than our intuition leads us to expect, truly random sequences look too ordered. Streaks of four or five heads in a row clash with our expectations, even though in a series of 20 tosses there is a 50 percent chance of getting four heads in a row, and a 25 percent chance of a streak of five. The law of averages (in fact, statisticians call it the "law of large numbers") ensures the expected even split only after a large number of tosses.
It is not uncommon for a player to make 50 percent of his shots and to take nearly 20 shots per game, so he stands a decent chance of making four or five shots in a row,and thus looking like he has a hot hand.
When the research team showed basketball fans a randomly generated sequence of X's and O's—OXXXOXXXOXXOOOXOOXXOO—and told the fans that the letters represented shots made and shots missed, 62 percent of subjects thought it constituted streak shooting even though the "hits" and "misses" had no effect whatsoever on one another.