We consider the impact of pre-launch reviews on sales of products of quality unknown to consumers. Sales occur simultaneously after consideration by a reviewer with a known level of bias. Consumers observe the reviewer’s decision and a private signal. Using convex analysis we prove three major...

While herding has long been suspected to play a role in financial market booms and busts, theoretical analyses have struggled to identify conclusive causes for the effect. Recent theoretical work shows that informational herding is possible in a market with efficient asset prices if information...