On the Optimal Size of Committees of Experts

What is the optimal size of expert committees? To address this question, I present a model of a committee of experts with career concerns. Each expert may observe an argument about the state of the world and is unsure about the argument s soundness. Experts may remain silent or compete for the opportunity to announce an argument. I show that experts become more reluctant to speak in larger committees. This effect is sufficiently strong to make small groups of experts optimal.