We first consider a closed model, where households' time discount depends on externality in consumption. We can prove that there is a unique steady state, which is a saddle point. Then we extend the model to a two‐country world, and derive the condition on the effects of consumption externality under which there is a unique free trade steady state with saddle‐point stability.

中文翻译：

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时间偏好和国际贸易

我们首先考虑一个封闭的模型，其中家庭的时间折扣取决于消费的外部性。我们可以证明存在唯一的稳态，这是一个鞍点。然后，我们将模型扩展到一个两个国家的世界，并得出关于消费外部性影响的条件，在这种条件下，存在一个具有鞍点稳定性的独特的自由贸易稳态。