Guns, Latrines, and Land Reform: Dynamic Pigouvian Taxation
研究了耐用消费品（如厕所和枪支）在动态经济中的最优庇古补贴与税收，发现政府承诺临时补贴可激励正外部性商品购买，而预期未来税收可能刺激负外部性商品提前购买，甚至导致政策放弃。
Dynamically and statically optimal Pigouvian subsidies and taxes on durables will differ in a growing economy. In a dynamic game, consumers may delay purchasing durables with positive externalities, such as latrines, anticipating greater future subsidies. Governments can most cheaply induce optimal purchasing by commiting to make subsidies temporary. Foreign donors may make commitment impossible, generating delays in private investment that more than fully offset the social benefits of transfers. Anticipated future taxes or regulation of durables with negative externalities, such as guns, may encourage current purchase, potentially causing policymakers who would otherwise prefer taxes or regulation to abandon such policies.