CeDEx workshop - Felix Vardy (Berkeley)

Passion over Reason? Mixed Motives and the Optimal Size of Voting Bodies

We study a Condorcet jury model where voters are driven both by passion (expressive motives) and by reason (instrumental motives). We show that arbitrarily small amounts of passion significantly affect equilibrium behavior and the optimal size of voting bodies. Increasing the size of voting bodies always reduces accuracy over some region. Unless conflict between passion and reason is very low, information does not aggregate in the limit. In that case, large voting bodies are no better than a coin flip at selecting the correct outcome. Thus, even when adding informed voters is costless, smaller voting bodies often produce better outcomes.

paper