Centre for Decision Research, Leeds University Business School, University of Leeds, Leeds, UK.
Department of Psychology, Wake Forest University, Winston-Salem, NC, USA.
Risk Anal. 2020 Apr;40(4):771-788. doi: 10.1111/risa.13431. Epub 2020 Jan 6.
Graphs are increasingly recommended for improving decision-making and promoting risk-avoidant behaviors. Graphs that depict only the number of people affected by a risk ("foreground-only" displays) tend to increase perceived risk and risk aversion (e.g., willingness to get vaccinated), as compared to graphs that also depict the number of people at risk for harm ("foreground+background" displays). However, previous research examining these "foreground-only effects" has focused on relatively low-probability risks (<10%), limiting generalizability to communications about larger risks. In two experiments, we systematically investigated the moderating role of probability size on foreground-only effects, using a wide range of probability sizes (from 0.1% to 40%). Additionally, we examined the moderating role of the size of the risk reduction, that is, the extent to which a protective behavior reduces the risk. Across both experiments, foreground-only effects on perceived risk and risk aversion were weaker for larger probabilities. Experiment 2 also revealed that foreground-only effects were weaker for smaller risk reductions, while foreground-only displays decreased understanding of absolute risk magnitudes independently of probability size. These findings suggest that the greater effectiveness of foreground-only versus foreground+background displays for increasing perceived risk and risk aversion diminishes with larger probability sizes and smaller risk reductions. Moreover, if the goal is to promote understanding of absolute risk magnitudes, foreground+background displays should be used rather than foreground-only displays regardless of probability size. Our findings also help to refine and extend existing theoretical accounts of foreground-only effects to situations involving a wide range of probability sizes.
图形越来越多地被推荐用于改善决策和促进风险规避行为。与仅显示受风险影响的人数的图形（“仅前景”显示）相比，显示受伤害风险的人数的图形（“前景+背景”显示）往往会增加感知风险和风险规避（例如，接种疫苗的意愿）。然而，以前研究这些“仅前景效应”的研究主要集中在低概率风险（<10%）上，限制了其对更大风险传播的适用性。在两项实验中，我们使用广泛的概率范围（从 0.1%到 40%）系统地研究了概率大小对仅前景效应的调节作用。此外，我们还研究了风险降低幅度的调节作用，即保护行为降低风险的程度。在两项实验中，对于较大的概率，仅前景对感知风险和风险规避的影响较弱。实验 2还表明，对于较小的风险降低幅度，仅前景效应较弱，而仅前景显示独立于概率大小而降低对绝对风险幅度的理解。这些发现表明，仅前景与前景+背景显示相比，增加感知风险和风险规避的效果随着概率大小的增加和风险降低幅度的减小而减弱。此外，如果目标是促进对绝对风险幅度的理解，则无论概率大小如何，都应使用前景+背景显示而不是仅前景显示。我们的发现还有助于将仅前景效应的现有理论解释细化和扩展到涉及广泛概率范围的情况。
