Responding to requests for help: Effects of payoff schemes with small monetary units

How do people react to different payment levels when asked to help a stranger perform a mundane task? The literature suggests a U-shaped relationship between a person's willingness to help and how much payment they are offered for the help, such that a small payment reduces willingness to help as compared to no payment or medium-sized payment. We report seven studies showing that when people are aware of the existence of distinct rewards for the same helping behavior, (1) most people behave as if they use a cutoff strategy; (2) individual response patterns are predictably heterogeneous; (3) people with lower household incomes are more likely to follow the pattern predicted by standard economic theory; and (4) joint evaluation of multiple payment levels (vs. separate evaluation) steers people toward the pattern predicted by standard economic theory. Subjective utility and reinforcements are discussed as potential sources of this heterogeneity. Our research contributes to understanding of how monetary payments affect helping behavior in prosocial contexts with small monetary units.