International Journal of Game Theory

, Volume 42, Issue 1, pp 55–98 | Cite as

Common learning with intertemporal dependence

  • Martin W. Cripps
  • Jeffrey C. Ely
  • George J. Mailath
  • Larry Samuelson


Consider two agents who learn the value of an unknown parameter by observing a sequence of private signals. Will the agents commonly learn the value of the parameter, i.e., will the true value of the parameter become approximate common-knowledge? If the signals are independent and identically distributed across time (but not necessarily across agents), the answer is yes (Cripps et al., Econometrica, 76(4):909–933, 2008). This paper explores the implications of allowing the signals to be dependent over time. We present a counterexample showing that even extremely simple time dependence can preclude common learning, and present sufficient conditions for common learning.


Common learning Common belief Private signals Private beliefs 

JEL Classification

D82 D83 


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Martin W. Cripps
    • 1
  • Jeffrey C. Ely
    • 2
  • George J. Mailath
    • 3
  • Larry Samuelson
    • 4
  1. 1.Department of EconomicsUniversity College LondonLondonUK
  2. 2.Department of EconomicsNorthwestern UniversityEvanstonUSA
  3. 3.Department of EconomicsUniversity of PennsylvaniaPhiladelphiaUSA
  4. 4.Department of EconomicsYale UniversityNew HavenUSA

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