On the Framing of Multiple Prospects

We investigated decisions involving multiple independent uncertain prospects. At the extremes, a decision maker may either consider each prospect as a separate event (segregation) or evaluate the overall distribution of outcomes (aggregation). Contrary to choice by segregation, people sometimes reject a single gamble but accept a repeated play. On the other hand, people tend to choose by segregation when a particular gamble is singled out from a larger ensemble. Similarly, physicians make different choices when they evaluate problems on a case-by-case basis than when they consider the broader picture. Peoples' tendency to segregate multiple prospects represents a significant violation of the standard theory of rational choice.