We present a new method for quantitatively documenting concerns for economic fairness. In particular we focus on the method’s potential for identifying variation in
prosociality within and across societies. Specifically, we conducted multiple dictator games per player in two small-scale societies. Each game presented the decision maker with a choice between an equitable and an inequitable payoff distribution. The games varied in terms of the type of inequality the decision maker faced and in terms of
the cost to the decision maker of eliminating inequality. This latter variation in cost is what makes the method suitable for identifying the price one is willing to pay for
equality. To analyze the data, we developed a novel set of statistical models that directly link experimental results and player heterogeneity with the formal theory of
inequality aversion. The paper concludes with a discussion of how the experimental method can be generalized to allow maximum flexibility in data analysis.