Book chapter

Information Aggregation in Political Decision Making (2019)

in: Oxford Research Encyclopedia of Politics


Information is of great value to politicians, who make decisions with uncertain consequences and want to convince the public and their political counterparts of the validity of their proposals. Because of conflicting interests and ideal views, information is not easily shared among political agents. However, information aggregation is collectively valuable, because it leads to better decision-making and facilitates defusing conflicts. Formal theorists investigate some of the institutions used to aggregate information among political agents.There are several studies on committee decision-making. They establish that rational voters do not make voting choices using only their individual information. This complicates information aggregation, especially when high quorum voting rules are adopted. However, deliberation may restore efficient information aggregation. In the case of homogeneous committees, strategic incentives for information acquisition are optimized by a decision mechanism based on random sequential individual consultations.The fundamental characteristic of committees is that all decisions are made jointly. An early 21st-century surge of formal studies on information aggregation considers the "opposite case" of information exchange among political entities that make decisions independently of each other. These articles deliver insights on topics as diverse as the optimal organization of meetings, the benefit of cabinet governments, the shape of political and social networks, and the value of engagement of societal groups. The breadth of these results is a testimony to the success and promise of this methodology.Of great importance for international conflict avoidance is building and maintaining trust among states and non-state entities. Formal analysis of international conflict management institutions such as standard diplomatic communications, peace summits, and third-party intermediation clarifies that, while none of these institutions fully prevent war, they are all useful to aggregate information, build trust, and facilitate peaceful agreements. Even communication through standard diplomatic channels and public announcements may significantly reduce the risk that disputes evolve into conflicts. Third-party intermediation is more effective, even if mediators are not endowed with the power to enforce their settlement proposals.