A Measure of Behavioral Heterogeneity

• Authors: Jose Apesteguia and Miguel Ángel Ballester
• American Economic Journal: Microeconomics, Vol. 18, No. 2, 1 - 21, May 2026

In this paper, we propose a novel way to measure behavioral heterogeneity in a population of stochastic individuals. Our measure is choice-based; it evaluates the probability that, over a randomly selected menu, the sampled choices of two sampled individuals differ. We provide axiomatic foundations for this measure and a decomposition result that separates heterogeneity into its intrapersonal and interpersonal components.