Robust multiplicity with (transfinitely) vanishing naiveté

We extend significantly a result in Heifetz and Kets (Theor Econ 18:415–465, 2018) for Carlsson and van Damme’s (Econometrica 61:989–1018, 1993) global games by which even slight deviations from common belief in infinite depth of reasoning restore the robustness of rationalizable actions multiplicity, in contrast with the intriguing findings of Weinstein and Yildiz (Econometrica 75:365–400, 2007) under an idealized lack of such deviations. Here we show that multiplicity of rationalizable actions is a robust phenomenon even if finite depth of reasoning is an ‘extremely remote rumor’, where someone suspects that someone suspects (...) that somebody might have a finite depth of reasoning, and where the dots range over a transfinite range.

[1]  Fabrizio Germano,et al.  Uncertain rationality, depth of reasoning and robustness in games with incomplete information , 2020 .

[2]  Yi-Chun Chen,et al.  Uniform Topologies on Types , 2009 .

[3]  Aviad Heifetz,et al.  Robust Multiplicity with a Grain of Naiveté , 2018 .

[4]  Yi-Chun Chen,et al.  The Weinstein-Yildiz Critique and Robust Predictions with Arbitrary Payoff Uncertainty ∗ , 2014 .

[5]  Stephen Morris,et al.  Topologies on Types , 2005 .

[6]  S. Zamir,et al.  Formulation of Bayesian analysis for games with incomplete information , 1985 .

[7]  Harold Simmons Fruitful and helpful ordinal functions , 2008, Arch. Math. Log..

[8]  Stephen Morris,et al.  Equilibrium Selection in Global Games with Strategic Complementarities , 2001, J. Econ. Theory.

[9]  A. Heifetz The bayesian formulation of incomplete information — The non-compact case , 1993 .

[10]  Stephen Morris,et al.  Common Belief Foundations of Global Games , 2015, J. Econ. Theory.

[11]  P. Billingsley,et al.  Convergence of Probability Measures , 1969 .

[12]  H. Carlsson,et al.  Global Games and Equilibrium Selection , 1993 .

[13]  Antonio Penta,et al.  On the structure of rationalizability for arbitrary spaces of uncertainty , 2013 .

[14]  Yi-Chun Chen,et al.  Characterizing the Strategic Impact of Misspecified Beliefs , 2016 .

[15]  Muhamet Yildiz,et al.  A Structure Theorem for Rationalizability with Application to Robust Predictions of Refinements , 2007 .

[16]  D. Fudenberg,et al.  Interim Correlated Rationalizability , 2007 .

[17]  Pedro Jara-Moroni,et al.  A dominance solvable global game with strategic substitutes , 2013 .

[18]  Rosemarie Nagel,et al.  One, Two, (Three), Infinity: Newspaper and Lab Beauty-Contest Experiments , 2000 .