Individuals tend to underprepare for rare, catastrophic events because of biases in risk perception. A simple form of broad bracketing—presenting the cumulative probability of loss over a longer time horizon—has the potential to alleviate these barriers to accurate risk perception and increase protective actions such as purchasing flood insurance. However, it is an open question whether broad bracketing effects last over time: There is evidence that descriptive probability information is ignored when decisions are based on “experience” (repeatedly and in the face of feedback), which characterizes many protective decisions. Across six incentive-compatible experiments with high stakes, we find that the broad bracketing effect does not disappear or change size when decisions are made from experience. We also advance our understanding of the mechanisms underlying broad bracketing, finding that, while cumulative probability size is a strong driver of the effect, this is dampened for larger brackets leading people to be less sensitive to probability size.

由于风险感知存在偏见，个人往往对罕见的灾难性事件的准备不足。粗略括弧式的简单形式（表示较长时间范围内的累计损失概率）具有减轻这些障碍的可能性，从而可以准确地识别风险并增加购买洪水保险之类的保护性措施。但是，广泛的括号效应是否会随着时间推移持续存在是一个悬而未决的问题：有证据表明，当决策基于“经验”（反复并面对反馈）时，描述性概率信息会被忽略，这是许多保护性决策的特征。在六个高风险激励兼容实验中，我们发现广泛的包围效应并没有当根据经验做出决策时，它们消失或改变大小。我们还进一步了解了广泛包围的潜在机制，发现虽然累积概率大小是影响结果的重要驱动因素，但对于较大的包围来说，这会有所减弱，从而导致人们对概率大小的敏感性降低。