Department of Psychology, University of Basel, Missionsstrasse 60/62, CH-4055 Basel, Switzerland.
J Exp Psychol Appl. 2012 Sep;18(3):314-30. doi: 10.1037/a0028279. Epub 2012 May 7.
How does the public reckon which risks to be concerned about? The availability heuristic and the affect heuristic are key accounts of how laypeople judge risks. Yet, these two accounts have never been systematically tested against each other, nor have their predictive powers been examined across different measures of the public's risk perception. In two studies, we gauged risk perception in student samples by employing three measures (frequency, value of a statistical life, and perceived risk) and by using a homogeneous (cancer) and a classic set of heterogeneous causes of death. Based on these judgments of risk, we tested precise models of the availability heuristic and the affect heuristic and different definitions of availability and affect. Overall, availability-by-recall, a heuristic that exploits people's direct experience of occurrences of risks in their social network, conformed to people's responses best. We also found direct experience to carry a high degree of ecological validity (and one that clearly surpasses that of affective information). However, the relative impact of affective information (as compared to availability) proved more pronounced in value-of-a-statistical-life and perceived-risk judgments than in risk-frequency judgments. Encounters with risks in the media, in contrast, played a negligible role in people's judgments. Going beyond the assumption of exclusive reliance on either availability or affect, we also found evidence for mechanisms that combine both, either sequentially or in a composite fashion. We conclude with a discussion of policy implications of our results, including how to foster people's risk calibration and the success of education campaigns.
公众如何判断哪些风险值得关注？可得性启发法和情感启发法是解释普通人如何判断风险的关键理论。然而，这两种理论从未被系统地进行过比较，也从未在不同的公众风险感知衡量标准中检验过它们的预测能力。在两项研究中，我们通过使用三种衡量标准（频率、统计生命价值和感知风险）和一组同质（癌症）和经典的异质死亡原因来衡量学生样本中的风险感知。基于这些风险判断，我们测试了可得性启发法和情感启发法的精确模型，以及可得性和情感的不同定义。总的来说，基于回忆的可得性启发法，即利用人们在社交网络中直接体验风险发生的情况的启发法，最符合人们的反应。我们还发现，直接经验具有高度的生态有效性（并且明显超过情感信息）。然而，与可得性相比，情感信息的相对影响在统计生命价值和感知风险判断中比在风险频率判断中更为显著。相比之下，在媒体上遇到风险的情况在人们的判断中几乎没有起到作用。我们的研究结果超越了对可得性或情感的单一依赖假设，还为结合两种机制的证据提供了依据，这些机制可以按顺序或复合方式结合。最后，我们讨论了我们的研究结果对政策的影响，包括如何促进人们的风险校准和教育活动的成功。
