Brown Philip, Daigneault Adam, Tjernström Emilia, Zou Wenbo
Landcare Research New Zealand.
University of Maine School of Forest Resources.
World Dev. 2018 Apr;104:310-325. doi: 10.1016/j.worlddev.2017.12.002. Epub 2017 Dec 28.
Natural disasters give rise to loss and damage and may affect subjective expectations about the prevalence and severity of future disasters. These expectations might then in turn shape individuals' investment behaviors, potentially affecting their incomes in subsequent years. As part of an emerging literature on endogenous preferences, economists have begun studying the consequences that exposure to natural disasters have on risk attitudes, perceptions, and behavior. We add to this field by studying the impact of being struck by the December 2012 Cyclone Evan on Fijian households' risk attitudes and subjective expectations about the likelihood and severity of natural disasters over the next 20 years. The randomness of the cyclone's path allows us to estimate the causal effects of exposure on both risk attitudes and risk perceptions. Our results show that being struck by an extreme event substantially changes individuals' risk perceptions as well as their beliefs about the frequency and magnitude of future shocks. However, we find sharply distinct results for the two ethnicities in our sample, indigenous Fijians and Indo-Fijians; the impact of the natural disaster aligns with previous results in the literature on risk attitudes and risk perceptions for Indo-Fijians, whereas they have little to no impact on those same measures for indigenous Fijians. To provide welfare implications for our results, we compare households' risk perceptions to climate and hydrological models of future disaster risk, and find that both ethnic groups over-infer the risk of future disasters relative to the model predictions. If such distorted beliefs encourage over-investment in preventative measures at the cost of other productive investments, these biases could have negative welfare impacts. Understanding belief biases and how they vary across social contexts may thus help decision makers design policy instruments to reduce such inefficiencies, particularly in the face of climate change.
自然灾害会造成损失和破坏，并可能影响人们对未来灾害发生概率和严重程度的主观预期。这些预期进而可能塑造个人的投资行为，从而潜在地影响他们未来几年的收入。作为关于内生偏好的新兴文献的一部分，经济学家们已开始研究遭受自然灾害对风险态度、认知和行为的影响。我们通过研究2012年12月的伊冯娜气旋对斐济家庭风险态度以及对未来20年自然灾害发生可能性和严重程度的主观预期的影响，为这一领域增添了新内容。气旋路径的随机性使我们能够估计受灾对风险态度和风险认知的因果效应。我们的研究结果表明，遭受极端事件会极大地改变个人的风险认知以及他们对未来冲击频率和强度的信念。然而，我们在样本中的两个族群——斐济原住民和印度裔斐济人身上发现了截然不同的结果；自然灾害的影响与之前关于印度裔斐济人风险态度和风险认知的文献结果一致，而对斐济原住民的这些指标几乎没有影响。为了探讨我们研究结果的福利含义，我们将家庭的风险认知与未来灾害风险的气候和水文模型进行了比较，发现两个族群相对于模型预测都过度推断了未来灾害的风险。如果这种扭曲的信念以牺牲其他生产性投资为代价鼓励对预防措施的过度投资，那么这些偏差可能会产生负面的福利影响。因此，了解信念偏差及其在不同社会背景下的差异，可能有助于决策者设计政策工具以减少此类低效率情况，尤其是在面对气候变化时。
