消費外部性、孝親動機與最適租稅

Consumption Externalities, Gift Motivation and Optimal Taxation

本文建構一個具孝親動機的疊代模型，以之探討消費外部性和孝親動機的相互作用以及對最適均衡?徑的影響。我們發現孝親動機的運作與否決定?消費外部性的扭曲管道。當孝親動機有效運作時，消費外部性只影響同時期?同世代的消費分配，最適租稅政策為贈與稅和資本所得稅。當孝親動機無效運作時，此時消費外部性?只影響個人的跨期消費分配，同時也影響?資本的?積?徑。最適租稅政策為資本所得稅和一組隨收隨付社會安全制?。 This paper builds an overlapping generations model with gift motivation and use it to study the interaction between consumption externalities and gift motivation, as well as the effects on optimality of the equilibrium path. We find that the operativeness of gift motivation determines the channels of distortion of consumption externalities. When the gift motive is operative, consumption externalities only affect the intratemporal allocation of consumption between the young and the old. The optimal tax policy consists of a tax on gift and a tax on capital income. When the gift motive is inoperative, consumption externalities not only affect the intertemporal allocation of consumption of an individual when young and when old but also modify the path of capital accumulation. The optimal tax policy in this case consists of a tax on capital income and a pay-as-you-go social security system.