Bar-Hillel Maya, Budescu David V, Amar Moty
Hebrew University at Jerusalem, Israel.
Psychon Bull Rev. 2008 Apr;15(2):278-83. doi: 10.3758/pbr.15.2.278.
Bar-Hillel and Budescu (1995) failed to find a desirability bias in probability estimation. The World Cup soccer tournament provided an opportunity to revisit the phenomenon in a context in which desirability biases are notoriously rampant. Participants estimated the probabilities of various teams' winning their upcoming games. They were promised money if one team-randomly designated by the experimenter-won its upcoming game. Participants assigned a higher probability to a victory by their target team than did other participants, whose promised monetary reward was contingent on the victory of its opponent. Prima facie, this seems to be a desirability bias. However, in a follow-up study that made one team salient, without promising monetary rewards, participants also judged their target team to be more likely to win. On grounds of parsimony, we conclude that what appears to be a desirability bias may just be a salience/marking effect, and-although optimism is a robust and ubiquitous human phenomenon-that wishful thinking still remains elusive.
巴-希勒尔和布德斯科（1995年）未能在概率估计中发现期望偏差。世界杯足球赛提供了一个契机，在一个期望偏差 notoriously rampant 的背景下重新审视这一现象。参与者估计了各支球队赢得即将到来比赛的概率。如果由实验者随机指定的一支球队赢得了即将到来的比赛，他们将获得金钱奖励。与承诺金钱奖励取决于对手获胜的其他参与者相比，参与者将目标球队获胜的概率估计得更高。乍一看，这似乎是一种期望偏差。然而，在一项后续研究中，在没有承诺金钱奖励的情况下突出了一支球队，参与者也认为他们的目标球队更有可能获胜。基于简约性，我们得出结论，看似期望偏差的现象可能只是一种显著性/标记效应，而且——尽管乐观是一种强大且普遍存在的人类现象——但一厢情愿的想法仍然难以捉摸。
