Attention for Sale: Endogenous Agenda Formation in Sequential vs. Simultaneous Debates

We model a competition between two debaters trying to capture the attention of a decision maker. In the model, the decision maker can only choose alternatives that are on the agenda and the agenda is endogenous. The debaters compete to put their alternatives on the agenda by participating in all-pay-auctions for a …nite number of attention slots. We compare simultaneous debates, in which all investments are taken before the debate, to sequential debates, in which investments can be taken along with the evolution of the agenda. In a simple model with complete information we highlight why sequential debates are preferable for the decision maker. We show the robustness of this result to several generalizations of the model including asymmetric information between the debaters.