A sender designs an information structure to persuade a receiver to take an action. The sender is ignorant about the receiver's prior, and evaluates each information structure using the receiver's prior that is the worst for the sender. I characterize the optimal information structures in this...

A decision maker (DM) determines a set of reactions that receivers can choose before senders and receivers move in a generalized competitive signaling model with two-sided matching. The DM’s optimal design of the unique stronger monotone signaling equilibrium (unique D1 equilibrium) is...