A Proof of Blackwell's Theorem

Eduardo Perez (1, 2)

1 ECON - Département d'économie (Sciences Po)
2 CEPR - Center for Economic Policy Research

This note gives a new proof of Blackwell’s celebrated result. The result is a bit stronger than the classical version since the action set and the prior are fixed, and only the utility of the decision maker varies. I show directly that a decision maker has access to a larger set of joint distributions over actions and states of the world if and only if her information improves in the garbling order.

Domaines: Economies et finances

Eduardo Perez. A Proof of Blackwell's Theorem. 2017. ⟨hal-03393159⟩