Karmarkar Uma R, Kupor Daniella
School of Global Policy.
Questrom School of Business.
J Exp Psychol Gen. 2023 Mar;152(3):906-920. doi: 10.1037/xge0001306. Epub 2022 Oct 13.
People face increasingly detailed information related to a range of risky decisions. To aid individuals in thinking through such risks, various forms of policy and health messaging often enumerate their causes. Whereas some prior literature suggests that adding information about causes of an outcome increases its perceived likelihood, we identify a novel mechanism through which the opposite regularly occurs. Across seven primary and six supplementary experiments, we find that the estimated likelihood of an outcome decreases when people learn about the (by- definition lower) probabilities of the pathways that lead to that outcome. This "unlikelihood" bias exists despite explicit communication of the outcome's total objective probability and occurs for both positive and negative outcomes. Indeed, awareness of a low-probability pathway decreases subjective perceptions of the outcome's likelihood even when its addition objectively increases the outcome's actual probability. These findings advance the current understanding of how people integrate information under uncertainty and derive subjective perceptions of risk. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
人们在一系列有风险的决策中面临着越来越详细的信息。为了帮助个人思考此类风险，各种形式的政策和健康信息通常会列举其成因。虽然一些先前的文献表明，添加有关结果成因的信息会增加其被感知的可能性，但我们发现了一种相反情况经常发生的新机制。在七个主要实验和六个补充实验中，我们发现，当人们了解到导致该结果的（根据定义较低的）路径概率时，该结果的估计可能性会降低。尽管明确传达了结果的总客观概率，但这种“不太可能”偏差仍然存在，并且在正面和负面结果中都会出现。事实上，即使低概率路径的加入客观上增加了结果的实际概率，对它的认知仍会降低对结果可能性的主观感知。这些发现推进了当前对人们在不确定性下如何整合信息以及如何得出风险主观认知的理解。（PsycInfo数据库记录（c）2023美国心理学会，保留所有权利）
