Econometrica: Sep, 2009, Volume 77, Issue 5

Decision Makers as Statisticians: Diversity, Ambiguity, and Learning

https://doi.org/10.3982/ECTA7501
p. 1371-1401

Nabil I. Al‐Najjar

I study individuals who use frequentist models to draw uniform inferences from independent and identically distributed data. The main contribution of this paper is to show that distinct models may be consistent with empirical evidence, even in the limit when data increases without bound. Decision makers may then hold different beliefs and interpret their environment differently even though they know each other's model and base their inferences on the same evidence. The behavior modeled here is that of rational individuals confronting an environment in which learning is hard, rather than individuals beset by cognitive limitations or behavioral biases.