Mental Accounts and the Mutability of Altruism: An Experiment with Online Workers
American Economic Review, March 2013
People exploit context-specific ambiguities as excuses to be less generous. I conduct an experiment with online workers to investigate how mental accounts, which associate sources of income with appropriate uses, provide such excuses. Subjects accrue income in an earnings account from a real-effort task and in a windfall account from a lottery. They are given a chance to share with another subject. When earnings are a large fraction of income, marginal windfall income has no effect on sharing. When earnings are small, marginal earned income has a negative effect. Subjects appear to pay selective attention to the largest account, rather than the total, to reduce sharing. My findings support a self-signalling model of prosocial behavior (Benabou & Tirole, 2011).