Cumulative lifetime stress exposure assessed by the STRAIN predicts economic ambiguity aversion

Abstract

Uncertainty is inherent in most decisions humans make. Economists distinguish between twotypes of decision-making under non-certain conditions: those involving risk (i.e., knownoutcome probabilities) and those that involve ambiguity (i.e., unknown outcome probabilities).Prior work has identified individual differences that explain risk preferences, but less is knownabout factors associated with ambiguity aversion. Here, we hypothesized that cumulativeexposure to major stressors over the lifespan might be one factor that predicts an individuals’ambiguity aversion. Across two studies (Study 1: n = 58, Mean age = 25.7; Study 2: n = 188, Mean age =39.81), we used a comprehensive lifetime stress exposure inventory (i.e., the Stress andAdversity Inventory for Adults, or STRAIN) and a standard economic approach to quantify riskand ambiguity preferences. Greater lifetime stress exposure as measured by the STRAIN,particularly in early life, was associated with higher aversion to ambiguity but not risk attitudes.