Speed, Accuracy, and Complexity (opens in new tab)

This paper studies when response time is informative about problem complexity. It revisits a canonical sequential-sampling model in which a decision-maker chooses when to stop acquiring costly information. Problem complexity is measured by the noise-to-signal ratio of the evidence process. Under exogenous stopping rules -- as when the decision-maker does not optimally adjust to problem complexity -- response time increases with complexity. B...