The delay-reward heuristic: What do people expect in intertemporal choice tasks?

Recent research has shown that risk and reward are positively correlated in many environments, and that people haveinternalized this association as a “risk-reward heuristic”: when making choices based on incomplete information, people inferprobabilities from payoffs and vice-versa, and these inferences shape their decisions. We extend this work by examiningpeople’s expectations about another fundamental trade-off — that between monetary reward and delay. In 2 experiments (totalN = 670), we adapted a paradigm previously used to demonstrate the risk-reward heuristic. We presented participants withintertemporal choice tasks in which either the delayed reward or the length of the delay was obscured. Participants inferredlarger rewards for longer stated delays, and longer delays for larger stated rewards; these inferences also predicted people’swillingness to take the delayed option. In exploratory analyses, we found that older participants inferred longer delays andsmaller rewards than did younger ones. All of these results replicated in 2 large-scale pre-registered studies with participantsfrom a different population (total N = 2138). Our results suggest that people expect intertemporal choice tasks to offer atrade-off between delay and reward, and differ in their expectations about this trade-off. This “delay-reward heuristic” offersa new perspective on existing models of intertemporal choice and provides new insights into unexplained and systematicindividual differences in the willingness to delay gratification