Econometrica: Jul, 2003, Volume 71, Issue 4

Finite Order Implications of Common Priors

https://doi.org/10.1111/1468-0262.00446
p. 1255-1267

Barton L. Lipman

I characterize the implications of the common prior assumption for finite orders of beliefs about beliefs at a state and show that in finite models, the only such implications are those stemming from the weaker assumption of a common support. More precisely, given any finite and any finite partitions model where priors have the same support, there is another finite partitions model with common priors that has the same th order beliefs and knowledge for all ≤.