Why did U.S. food retailers voluntarily pledge to go cage-free with eggs?
建立了一个零售商之间的供应竞争模型，分析自愿承诺销售散养鸡蛋的经济动机，发现竞争可能导致囚徒困境，而动态条件下零售商可能通过集体承诺实现更高利润。
Abstract I develop a model of provision competition between food retailers to examine one potential economic rationale behind voluntary cage-free egg pledges. I show that competition pushes retailers to a prisoners’ dilemma equilibrium where retailers incur fixed costs to offer both non-cage-free and cage-free eggs to steal or prevent the loss of some basket-shopping consumers. In a dynamic setting, retailers can potentially sustain an equilibrium of higher profits by collectively withholding non-cage-free eggs. I show that changing supply conditions and consumer trends could have led to such an equilibrium with pledges acting as a signal to potentially facilitate tacit coordination.