Constructive Blackwell’s Theorem
Itai Arieli, Yakov Babichenko, Fedor Sandomirskiy · 2025
Blackwell's celebrated theorem is a cornerstone of information economics, establishing a necessary and sufficient condition for when a distribution F of posterior means can be induced from a prior G: namely, if and only if F majorizes G. While this result provides a deep understanding of the structure of feasible belief distributions, it is non-constructive and does not explain how to design a signal that achieves a given F.