Evolution and Adaptation: Ambiguity Attitudes with Optimal Risk Preferences

该奖项资助经济理论方面的研究。该项目旨在推动经济学家如何研究在环境和可能的结果不确定时必须做出决定的个人。人们通常会避免这种情况，宁愿选择安全的、容易理解的选择，而不是那些看起来有风险的、不确定的或利益模糊的选择。了解风险和模糊性是如何影响选择的，这不仅对预测诸如储蓄、投资、教育和工作选择等一系列个人决策很重要。这种经济理论在评估不同政策、技术变革或其他经济因素对经济的影响时也很重要。毫不奇怪，对风险的模糊性厌恶和悲观态度在宏观经济学和金融学的应用中发挥了越来越大的作用。这项研究工作将弥补我们当前经济理论中的一个空白。它将提供一个更好的模型，说明个人如何利用有关风险和模糊情况的新信息。该模型还将帮助我们了解不同个体对风险和模糊性的态度是如何比较的。最后，新理论可能提供更清晰的预测。该团队将使用基于进化和适应的方法来建立这个新理论。该项目可以开发新的工具，供企业经理和政策制定者使用，他们经常必须对客户、员工、公民和其他个人在危险情况下的行为做出准确预测。虽然现在有大量的研究为模糊和风险规避模型提供了决策理论基础，但对于进化如何在相互竞争的模型和方法之间进行选择，我们所知甚少。本项目将通过为一个新的模型——适应性模型——提供一个进化基础来推进关于风险和模糊性的基本理论，该模型对模糊性和风险规避施加了重要的结构。重要的特征是，偏好应该是动态一致的，即使以结果主义为代价，在风险背景下，不同的模糊性偏好与预期效用理论的背离密切相关。根据基因型的个体如何有效地适应其表型的表达，适应性模型可以将文献中几个突出模型的变体作为特殊情况嵌套。这将允许基于一组新的原始假设对这些模型进行评估，并将扩展关于不确定性下偏好结构的一般见解及其更新到这些模型在金融，宏观和政策选择背景下的应用。该项目还将有助于加强决策理论和进化生物学领域之间的跨学科桥梁。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award funds research in economic theory. The project seeks to advance how economists study individuals who must make decisions when the environment and possible outcomes are uncertain. People often appear to avoid these kinds of situations, preferring to safe and well-understood options over choices that seem risky, uncertain, or ambiguous in their benefits. Understanding how risk and ambiguity affect choices is important not only for predicting a host of individual decisions, such as saving, investment, education, and job selection. This kind of economic theory is also important assessing the impact of different policies, technological changes, or other economic factors on the economy. Not surprisingly, ambiguity aversion and pessimistic attitudes towards risk have played an ever-increasing role in applications to macroeconomics and finance. The research effort will address a gap in our current economic theory. It will provide a better model of how individuals make use of new information about risky and ambiguous situations. The model will also help us understand how attitudes towards risk and ambiguity compare across individuals. Finally, the new theory may offer sharper predictions. The team will use an approach based on evolution and adaptation to build this new theory. The project could develop new tools for use by business managers and policymakers, who often must form accurate predictions of how customers, employees, citizens, and other individuals will behave in risky situations. While there is now an abundance of research providing decision-theoretic foundations to models of ambiguity and risk aversion, much less is known about how evolution might select between competing models and approaches. This project will advance basic theory regarding risk and ambiguity by providing an evolutionary foundation for a new model, the adaptive model, that imposes significant structure on ambiguity and risk aversion. Important features will be that preferences should be dynamically consistent, even at the cost of consequentialism, and that different ambiguity preferences go hand in hand with departures from expected utility theory in the context of risk. Depending on how effectively individuals of a genotype can adapt the expression of their phenotype, the adaptive model can nest variants of several prominent models in the literature as special cases. This will permit the evaluation of these models based on a new set of primitive assumptions and will extend the general insights about the structure of preferences under uncertainty and their updating to applications of those models in the contexts of finance, macro and policy choice. The project will also help strengthen the interdisciplinary bridge between the fields of decision theory and evolutionary biology.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.