为什么最好雇个乐观者?——模糊性下的最优合同Who to Hire,Optimists or Pessimists?——Optimal Contract Under Ambiguity
姚东旻,王麒植,崔琳,李军林
摘要(Abstract)：
人们在决策时如果无法获知相关事件的发生概率,便称为人们面临模糊性(ambiguity)决策。此时Savage的主观期望效用模型将不再适用于刻画决策者的行为,前沿的决策理论通过引入模糊性感知和模糊性态度对该模型进行了修正。基于此,本文利用基于NAC(neo-additive capacity)的容度效用模型研究了模糊性下雇佣关系中的最优合同问题,发现:(1)由于决策方式的不同,乐观的雇员更容易被激励,因而他们往往能够给雇佣者带来更大的利润;(2)模糊性是合约设计中十分重要的考虑因素,忽略了不确定性,任何理论上的最优合约都可能失效。本文也解释了为什么企业文化中经常提倡积极态度(如乐观主义),以及为什么大量创业公司在初期盈利较好,发展壮大后反而衰落等现象,因而对理解企业的行为、发展以及合同设计提供了新的视角和理论框架。
关键词(KeyWords)： 模糊性;最优合同;NAC容度效用模型;模糊性态度;模糊性感知
基金项目(Foundation):
作者(Author): 姚东旻,王麒植,崔琳,李军林
DOI: 10.16513/j.cnki.cje.2015.04.004
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- ①Al-Najjar and Weinstein(2009)、Etner et al.(2012)很好地总结了此领域的研究并全面地对比了几种不同方法。
- ②见Ghirardato et al.(2004)。
- ①下一节各个效用函数模型提供了更多介绍。
- ①本文并不打算花太多精力讨论外部收益大小的影响,因为此分析结果与标准模型下结果类似。