Department of Cognitive, Perceptual and Brain Sciences, University College London, London WC1H 0AP, United Kingdom.
J Exp Psychol Learn Mem Cogn. 2011 Nov;37(6):1571-8. doi: 10.1037/a0024195. Epub 2011 Jul 18.
Verbal probability expressions are frequently used to communicate risk and uncertainty. The Intergovernmental Panel on Climate Change (IPCC), for example, uses them to convey risks associated with climate change. Given the potential for human action to mitigate future environmental risks, it is important to understand how people respond to these expressions. In 3 studies employing a novel manipulation of event severity (so as to avoid any confound with event base rate), we demonstrated a systematic effect of event severity on the interpretation of verbal probability expressions. Challenging a previous finding in the literature, expressions referring to a severe event were interpreted as indicating a higher probability than those referring to a more neutral event. The finding was demonstrated in scenarios communicating risks relating to climate change (Studies 1 and 2) and replicated in scenarios involving nanotechnology and nuclear materials (Study 3). This is the first direct demonstration of an effect of outcome severity on the interpretation of verbal probability expressions, correcting a previous (potentially problematic) conclusion attributable to a flawed experimental design.
口头概率表达经常用于传达风险和不确定性。例如，政府间气候变化专门委员会（IPCC）使用它们来传达与气候变化相关的风险。鉴于人类采取行动减轻未来环境风险的潜力，了解人们对这些表达的反应非常重要。在 3 项研究中，我们采用了一种新颖的事件严重程度的操纵（以避免与事件基本比率发生任何混淆），我们证明了事件严重程度对口头概率表达的解释有系统的影响。与文献中的先前发现相反，与严重事件相关的表达被解释为表示更高的概率，而与更中性的事件相关的表达则表示更高的概率。该发现是在与气候变化相关的风险情景（研究 1 和 2）中证明的，并在涉及纳米技术和核材料的情景中得到了复制（研究 3）。这是第一个直接证明结果严重程度对口头概率表达解释的影响的实验，纠正了先前归因于实验设计缺陷的（潜在有问题的）结论。
