New Developments in Social Choice and Bargaining Theory: Welfarism and Incomplete Information

这项研究项目有两个主要目标。首先，它通过放弃福利主义假设，为社会选择和讨价还价理论中的一些经典解决方案提供了经济学基础。其次，它提出了将这两个理论扩展到不完全信息问题的可能方法。在公理讨价还价和社会选择方面的大部分贡献都是用效用来表述的。因此，通常隐含地假设，如果两个问题在效用空间中重合，则它们一定有相同的解。不幸的是，这种福利主义假设既缺乏明确的规范性内容，也缺乏积极的内容，因此很难被接受为公理。这一研究项目通过描述其在非福利主义环境中的一些主要解决方案，为社会选择和公理讨价还价提供了更好的基础。长期以来，信息问题一直被认为是经济理论的核心。然而，它们对合作的影响仍然没有得到很好的理解。因此，奥曼教授在2000年向博弈论学会发表的主席讲话中将这一主题列为未来研究的重要方向。更准确地说，已经投入了大量的工作来了解哪些合同在不对称信息下是可行的，参看。机构设计理论。2007年瑞典央行授予赫维茨、马斯金和迈尔森教授经济学奖，以纪念阿尔弗雷德·诺贝尔，以表彰他们在这一主题上的开创性贡献。然而，在那些可行的合同中，人们对应该或将选择什么具体合同知之甚少。这个项目探索了许多不同的途径来将讨价还价和社会选择理论扩展到不完全信息。社会选择和公理讨价还价理论得到了广泛的应用，但它所基于的福利主义假设在没有理由的情况下并不令人信服。目前的研究项目将展示如何完成一些经典的公理系统，以在非福利主义框架下推导出福利主义的解。到目前为止，关于不完全信息下的社会选择和讨价还价的工作很少，但显然需要超越仅仅描述什么是可行的。更广泛的影响：这项研究提案的重点是基础性的。所审议问题的重要性意味着它可能对许多不同的实际经济问题产生重大影响。不完全信息下的规范分析应该指导经济和社会辩论，例如关于公共医疗保险、税收或成本分担的辩论。这项研究的一部分将与其他三所大学的研究人员合作开展：Camelia Bejan(莱斯大学)、David Perez-Castrillo(西班牙巴塞罗那自治大学)和David Wettstein(本古里安大学，以色列)。这一研究项目的结果将被整合到一门研究生级别的课程中，该课程由研究人员在布朗大学教授，内容涉及信息、风险和不确定性。

This research project has two main objectives. First, it offers an economic foundation of some classical solutions in the theories of social choice and bargaining by dropping the welfarist assumption. Second, it suggests possible ways of extending these two theories to problems with incomplete information.Most contributions in axiomatic bargaining and social choice are phrased in utilities. It is thus assumed, often implicitly, that two problems must have the same solution if they coincide in the utility space. Unfortunately, this welfarist assumption lacks both a clear normative and positive content, and is thus hard to accept as an axiom. This research project offers a better foundation of social choice and axiomatic bargaining by characterizing some of its main solutions in non-welfarist environments.Informational issues have long been recognized as central in economic theory. However, their implications on cooperation are still not yet well understood. Accordingly, Professor Aumann listed this topic as an important direction for future research in his 2000 presidential address to the Game Theory Society. To be more precise, an impressive amount of work has already been devoted to understand which contracts are feasible under asymmetric information, cf. the theory of mechanism design. Professors Hurwicz, Maskin, and Myerson were awarded the 2007 Sveriges riksbank prize in economic sciences in memory of Alfred Nobel for their path-breaking contributions on the topic. Yet very little is known about what specific contract, among those that are feasible, should or will be chosen. This project investigates many different avenues to extend the theories of bargaining and social choice to incomplete information.The theories of social choice and axiomatic bargaining are widely applied, yet the welfarist assumption on which it is founded is not compelling without justification. The present research project will show how some classical axiomatic systems can be completed to derive welfarist solutions in non-welfarist frameworks. Very little work has been done so far on social choice and bargaining under incomplete information, yet there is a clear need of going beyond the mere description of what is feasible.Broader Impact: This research proposal is foundational in its focus. The importance of the questions considered implies that it could have a significant impact on many different practical economic problems. The normative analysis under incomplete information should guide the economic and social debates, concerning, for instance, public health insurance, taxes, or cost sharing. Part of this research will be developed in collaboration with researchers from three other universities: Camelia Bejan (Rice U), David Perez-Castrillo (Universitat Autonoma de Barcelona, Spain), and David Wettstein (Ben Gurion University, Israel). The results of this research project will be integrated into a graduate-level course on information, risk and uncertainty that the investigator teaches at Brown University.