The Voluntary Provision of Public Goods under Varying Income Distributions.

The T. C. Bergstrom, L. E. Blume, and H. R. Varian (1986) model of voluntary contributions to public goods predicts increases in public good provision as the distribution of income becomes more unequal. This model is tested in the laboratory. Group behavior conforms to the model but individual behavior does not. Individuals with low incomes overcontribute to the public good; individuals with high incomes undercontribute. Coauthors are Stuart Mestelman, Rob Moir, and R. Andrew Muller.