Rationalizability, Observability, and Common Knowledge

• 成果类型: Article
• 署名作者: Penta, Antonio; Zuazo-Garin, Peio
• 署名单位: Pompeu Fabra University; ICREA; HSE University (National Research University Higher School of Economics)
• 刊物名称: REVIEW OF ECONOMIC STUDIES
• ISSN/ISSBN: 0034-6527
• DOI: 10.1093/restud/rdab047
• 发表日期: 2022
• 页码: 948-975
• 关键词: information structures; robust predictions; strategic behavior; Structure theorem; global games; equilibrium; beliefs; implementation; hierarchies; COMMITMENT

摘要

We study the strategic impact of players' higher-order uncertainty over the observability of actions in general two-player games. More specifically, we consider the space of all belief hierarchies generated by the uncertainty over whether the game will be played as a static game or with perfect information. Over this space, we characterize the correspondence of a solution concept which captures the behavioural implications of Rationality and Common Belief in Rationality (RCBR), where rationality is understood as sequential whenever the game is dynamic. We show that such a correspondence is generically single-valued, and that its structure supports a robust refinement of rationalizability, which often has very sharp implications. For instance, (1) in a class of games which includes both zero-sum games with a pure equilibrium and coordination games with a unique efficient equilibrium, RCBR generically ensures efficient equilibrium outcomes (eductive coordination); (2) in a class of games which also includes other well-known families of coordination games, RCBR generically selects components of the Stackelberg profiles (Stackelberg selection); (3) if it is commonly known that player 2's action is not observable (e.g. because 1 is commonly known to move earlier, etc.), in a class of games which includes all of the above RCBR generically selects the equilibrium of the static game most favourable to player 1 (pervasiveness of first-mover advantage).