Environmental incentives are characterized by two distinct features: (1) a benefit-cost trade-off; and (2) private information about the trade-off. This suggests a degree of freedom of where to attach the private information, either to the benefit or the costs, as long as these choices imply the same behavior absent incentives (‘observation equivalent’). However, we show that different observation equivalent specifications can lead to different incentives. This is demonstrated for two cases: rainforest protection and contributions to a public good. Therefore, the choice of a private information parameter must be justified against observation equivalent alternatives.

环境激励具有两个明显的特征：（1）收益-成本权衡；(2) 关于权衡的私人信息。这表明了在哪里附加私人信息的一定程度的自由度，无论是收益还是成本，只要这些选择意味着没有激励的相同行为（“观察等价”）。然而，我们表明不同的观察等效规范可以导致不同的激励。这体现在两个案例中：雨林保护和对公共产品的贡献。因此，私有信息参数的选择必须根据观察等效替代方案来证明是合理的。