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The "hot-hand fallacy" (also known as the "hot hand phenomenon" or "hot hand") is the fallacious belief that a person who has experienced success with a random event has a greater chance of further success in additional attempts. The concept has been applied to gambling and sports, such as basketball. While a previous success at a skill-based athletic task, such as making a shot in basketball, can change the psychological behavior and subsequent success rate of a player, researchers have often found little evidence for a true "hot hand" in practice. It has been reported that a belief in the hot-hand fallacy affects a player's perceptions of success. However a 2015 examination of the original papers by Joshua Miller and Adam Sanjurjo found flaws in the methodology and showed that, in fact, the hot hand fallacy may not exist. It may be attributable to a misapplication of statistical techniques. 〔http://www.wsj.com/articles/the-hot-hand-debate-gets-flipped-on-its-head-1443465711〕 ==Discovery== Three researchers discovered the fallacy, with Thomas Gilovich and Amos Tversky acting as the primary investigators. Gilovich's primary focus was on judgment, decision-making behaviors and heuristics,〔(【引用サイトリンク】url=http://gilovich.socialpsychology.org/ )〕 while Amos Tversky came from a cognitive and mathematical psychology background. The pair collaborated with Robert Vallone, a cognitive psychologist, and all three became pioneers of the hot hand fallacy theory. Their study, "The Hot Hand in Basketball: On the Misperception of Random Sequences" (1985), investigated the validity of people's thoughts on "hot" shooters in basketball. The "Hot Hand in Basketball" study provided a large body of evidence that disproved the theory the basketball players have "hot hands", that is, that they are more likely to make a successful shot if their previous shot was successful. The study looked at the inability of respondents to properly understand randomness and random events; much like innumeracy can impair a person's judgement of statistical information, the hot hand fallacy can lead people to form incorrect assumptions regarding random events. The three researchers provide an example in the study regarding the "coin toss"; respondents expected even short sequences of heads and tails to be approximately 50% heads and 50% tails. The study proposed two biases that are created by the kind of thought pattern applied to the coin toss: it could lead an individual to believe that the probability of heads or tails increases after a long sequence of either has occurred (known as the gambler's fallacy); or it could cause an individual to reject randomness due to a belief that a streak of either outcome is not representative of a random sample.〔 The first study was conducted via a questionnaire of 100 basketball fans from the colleges of Cornell and Stanford. The other looked at the individual records of players from the 1980–81 Philadelphia 76ers. The third study analyzed free-throw data and the fourth study was of a controlled shooting experiment. The reason for the different studies was to gradually eliminate external factors around the shot. For example, in the first study there is the factor of how the opposing team's defensive strategy and shot selection would interfere with the shooter. The second and third take out the element of shot selection, and the fourth eliminates the game setting and the distractions and other external factors mentioned before. The studies primarily found that the outcomes of both field goal and free throw attempts are independent of each other.〔 In the later studies involving the controlled shooting experiment the results were the same; evidently, the sense of being "hot" does not predict hits or misses.〔 A 2003 paper noted that Gilovich et al. did not examine the statistical power of their own experiments. By performing power analysis on the 1985 data, the researchers concluded that even if the Philadelphia 76ers did shoot in streaks, it is highly unlikely that Gilovich, Vallone and Tversky would have discovered that fact. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hot-hand fallacy」の詳細全文を読む スポンサード リンク
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