Minson Julia A, Umphres Christopher
Harvard Kennedy School, Harvard University.
Psychol Sci. 2020 Aug;31(8):927-943. doi: 10.1177/0956797620921517. Epub 2020 Jul 6.
Across seven studies (combined = 5,484), we demonstrated that confidence in one's judgments decreases over a series of quantitative estimates. This finding was robust to various methods of confidence elicitation, the presence of incentives, and different estimation topics (Studies 1, 2, and 4). Our results also stand in contrast to participant expectations (Study 3). The phenomenon does not appear to be driven by fatigue, lack of effort, or various explanations based on incorporating uncertainty from prior judgments into subsequent ones. Our findings suggest that rather than evaluating confidence in isolation, participants evaluate confidence in reference to their stated confidence on earlier judgments. We theorize that confidence in earlier judgments increases in hindsight because of biased forgetting of disconfirming evidence. As a result, confidence in subsequent judgments appears to be comparatively lower (preregistered Studies 5-7). We discuss the implications for confidence research and consumer, organizational, and policy decision-making.
在七项研究（总计5484人）中，我们证明了在一系列定量估计过程中，人们对自己判断的信心会逐渐降低。这一发现对于各种信心诱导方法、激励措施的存在以及不同的估计主题（研究1、2和4）都很稳健。我们的结果也与参与者的预期形成对比（研究3）。这种现象似乎不是由疲劳、缺乏努力或基于将先前判断中的不确定性纳入后续判断的各种解释所驱动的。我们的研究结果表明，参与者并非孤立地评估信心，而是参照他们对早期判断所陈述的信心来评估信心。我们推测，由于对不支持证据的有偏差遗忘，事后看来对早期判断的信心会增加。因此，对后续判断的信心似乎相对较低（预注册研究5 - 7）。我们讨论了这一发现对信心研究以及消费者、组织和政策决策的影响。
