A Dual Perspective on Information Design

The problem of optimally designing information for multiple agents who interact in a game can be formulated as a linear program. We explore its dual representation and show that it provides a novel perspective and new economic insights into the information-design problem. Through the lens of the dual, we identify general properties that hold for all information-design problems. Duality also offers a portable, general, method for computing solutions. We illustrate this approach in the context of simple investment games.