Experimental Studies of Desirability Bias in Predictive Judgment

大多数重要的决策都涉及对未来的预测。例如，决定是否购买某一特定的房子，可能涉及到预测家庭规模的变化，未来社区的构成，以及个人未来的就业和收入。大多数其他重要的个人决定以及医学、法律、商业和公共政策等领域的专业决定也是如此。这项研究解决的问题是，这些预测是否受到“一厢情愿的想法”的影响。人们对未来会发生什么的预测是否受到他们希望发生的事情的影响？例如，一对夫妇想要一套特定的房子，因此希望能够支付还款，这一事实是否会导致他们对未来的就业和收入做出过于乐观的预测？这显然是一个重要的问题，因为这种一厢情愿的想法可能会导致糟糕的决定。例如，这可能会导致前面提到的夫妇未能预料到裁员，从而导致他们的抵押贷款丧失赎回权。过去对一厢情愿的研究结果并不一致，一些研究人员发现人们的欲望对他们的预测有很强的影响，而另一些研究人员发现这种影响很弱或没有影响。本研究的目的是测试一个新开发的框架来整合这些不一致的结果。这个框架规定了六个条件，在这些条件下，一厢情愿的想法特别可能发生。对文献的回顾表明，这些条件在以前的研究中基本上得到了满足，这些研究显示了一厢情愿的想法，但在未能证明这一点的研究中却没有。这六个条件是：1)事件发生的愿望是强烈的；2)事件是否会发生高度不确定的；3)没有强烈的动机来预测准确的；4)预测任务是复杂的，需要搜索和整合许多信息；5)事件被认为至少部分地在做出预测的人的控制之下。6)预测采用确定性的“是-否”形式，而不是概率形式。这项研究将包括几个实验，在这些实验中，大学生和其他人对一系列未来事件做出预测，包括体育比赛、政治选举和轮盘赌等机会游戏。通过操纵这些事件的可选结果的可取性，以及框架的六个条件是否都得到满足，可以确定当这些条件得到满足时，一厢情愿的想法是否更有可能发生。这项研究的结果是，对一厢情愿的科学理解，它的原因，以及它最有可能发生的条件将大大扩展。这将使研究人员能够开发出避免一厢情愿的方法，帮助人们做出更好的决定。

Most important decisions involve making predictions about the future. The decision whether or not to buy a particular house, for example, might involve predicting changes in the size of one's family, the composition of the prospective neighborhood, and one's future employment and income. The same is true of most other important personal decisions and also professional decisions in fields like medicine, law, business, and public policy. The question addressed by this research is whether these kinds of predictions are influenced by "wishful thinking." Are people's predictions about what will happen in the future influenced by what they want to happen? For example, does the fact that a couple wants a particular house--and therefore wants to be able to make the payments--cause them to make overly optimistic predictions about their future employment and income? This is clearly an important question because this kind of wishful thinking could lead to poor decisions. For example, it could cause the aforementioned couple to fail to anticipate a job layoff that results in foreclosure on their mortgage. The results of past research on wishful thinking are inconsistent,with some researchers finding strong effects of people's desires on theirpredictions and others finding weak or null effects. The goal of thepresent research is test a newly developed framework for integrating theseinconsistent results. This framework specifies six conditions under whichwishful thinking is especially likely to occur. A review of theliterature suggests that these conditions were largely met in previousstudies that demonstrated wishful thinking, but not in research thatfailed to demonstrate it. The six conditions are 1) the desire that theevent occur is strong, 2) whether or not the event is going to occur ishighly uncertain, 3) there is no strong incentive for the prediction to beaccurate, 4) the prediction task is complex, requiring the search for andintegration of many pieces of information, 5) the event is perceived asbeing at least partly under the control of the person making theprediction, and 6) the prediction takes a deterministic "yes-no" formrather than a probabilistic form. The research will consist of several experiments in which collegestudents and others make predictions about a broad range of future eventsincluding sporting contests, political elections, and games of chance likeroulette. By manipulating both the desirability of the alternativeoutcomes of these events and whether or not each of the six conditions ofthe framework are met, it will be determined whether wishful thinking isin fact more likely when those conditions are satisfied. As a result of this research, scientific understanding of wishfulthinking, its causes, and the conditions under which it is most likely tooccur will be greatly expanded. This will allow researchers to developmethods for avoiding wishful thinking to help people make betterdecisions.