In this paper, we investigate the necessary and sufficient conditions for a decision maker to be monotone risk averse and left-monotone risk averse, respectively, in cumulative prospect theory (CPT). Our results show that the decision maker is more pessimistic than greedy if she is either monotone or left-monotone risk averse, which is similar to that of Chateauneuf et al. (Econ Theory 25(3):649–667, 2005) in the rank-dependent expected utility model. Detailed examples are presented to illustrate the main theorems. With this work, we make a progress in the characterizations of risk aversion in CPT, which is essential in understanding the features of CPT and its applications in finance and insurance.

中文翻译：

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累积前景理论中的风险规避特征

在本文中，我们研究了累积前景理论（CPT）中决策者分别成为单调风险厌恶者和左单调风险厌恶者的充要条件。我们的结果表明，如果决策者是单调或左单调的风险厌恶者，则比贪婪者更为悲观，这与Chateauneuf等人的观点类似。（Econ Theory 25（3）：649–667，2005）在依赖于等级的期望效用模型中。给出了详细的示例以说明主要定理。通过这项工作，我们在CPT的风险规避特性方面取得了进展，这对于理解CPT的功能及其在金融和保险中的应用至关重要。