Low socioeconomic status amplifies the perceived rarity of large rewards

Decision-making relies on heuristics derived from past experiences. Past experiences are likely to vary with socioeconomic status. We investigate socioeconomic differences in people’s reliance on a risk-reward heuristic, which exploits the tendency for larger rewards to be less probable. We analyze participants’ probability estimates in a lottery experiment and vignettes describing competitive search for resources. We find — and replicate— that participants with lower socioeconomic status (n = 144) assume a stronger negative relationship between payoffs and probabilities, viewing larger payoffs as less probable, but often smaller payoffs as more probable, than participants with higher socioeconomic status (n = 154). In simulations, we show that this relationship is expected under conditions of scarcity and high competition when foraging for resources. We suggest that the heuristics used by people with lower socioeconomic status are a concrete adaptation to experiences of scarcity. This means that psychological differences will persist unless redistributive actions remedy the scarcity driving them.