Time: 2024/03/19 15:10-18:00
Location: Room 313, Teaching Building No.2 (第二教学楼), Peking University
Speaker：Weiwei Chen (Department of Philosophy, Sun Yat-sen University)
Title：An Axiomatic Approach to Collective Decision-Making through Abstract Argumentation: Static and Dynamic Perspectives
Abstract：
In this talk, I present an axiomatic approach to collective decision-making based on abstract argumentation. I begin with an introduction of abstract argumentation frameworks, followed by the axiomatic method in social choice theory and we pay special attention to Arrow's Impossibility Theorem and May's Theorem on the characterization of the majority rule. Then, I introduce an axiomatic study of the preservation of semantic properties of Dung's argumentation frameworks during the aggregation of attack-relations. I also introduce a study on how to relax preservation requirements or axioms of aggregation rules to make preservation possible.
The first part of the talk examines aggregation processes in static terms, focusing on preserving semantic properties at a given time. In contrast, the second part of the talk investigates whether decisions remain rational when the preservation process is dynamic, meaning that it can incorporate new information. To address the dynamic nature of collective argumentation, we introduce the revision and contraction operators. These operators reflect the idea that when an individual or a group learns something new by accepting or rejecting an argument, they have to update their collective decision accordingly. Our study examines whether the order of revising individual opinions and aggregating them affects the final outcome, i.e., whether aggregation and revision commute.
本次报告将基于抽象论辩框架和公理化方法讨论集体决策问题。我首先介绍一个简洁的论辩系统，即抽象论辩框架，随后我将介绍社会选择理论中的公理化方法，并着重分析 Arrow 不可能性定理和 May 定理对于多数原则刻画。接着，我将引入一个公理化研究，探讨在聚合攻击关系的过程中，如何保留论辩框架的语义性质。同时，我还会讨论如何放松聚合规则的要求或公理，以实现语义性质的保留。
报告的第一部分从静态角度考察聚合过程，重点关注在特定时间点语义性质保留问题。相比之下，报告的第二部分将讨论当聚合过程变得动态时，即可以纳入新信息时，决策是否仍然保持理性。为了解决集体论辩的动态性，我们将引入修正和收缩算子。这些算子反映了这样一个概念：当个人或群体学到新知识时，他们需要相应地更新集体决策。我们将探讨修正和聚合的先后顺序是否会影响最终结果。
Bio: 陈伟伟，中山大学哲学系及逻辑与认知研究所副教授，专注于形式论证（formal argumentation）和社会选择理论（social choice theory）。他的研究位于论证学、逻辑学、决策论交汇处，着重探讨群体决策问题。