社會地位、生產外部性與最適租稅：一個小型開放經濟分析

Social Status, Productive Externality, and Optimal Taxation under a Small Open Economy

本文將個人具有追求「社會地位（social status）」的動機引入Turnovsky（1999）的開放總體經濟模型中，以進行最適政策(optimal policy)之討論。文中所提及之「社會地位」將以個人的相對財富（relative wealth）的方式來呈現；而財富則是由本國資本與外國債券共同組成。我們得到在個人存在追求社會地位的動機時，即使資本具有正的生產外部性，政府的最適政策將可能是對資本課稅而非補貼；此外，我們也將說明個人「消費對外國債券」的邊際替代率（marginal rate of substitution）在政府的最適稅率決策中扮演一關鍵性的角色。

We introduce the relative wealth holding into agent’s utility as a motive of status seeking in the endogenous growth model of a small open economy and evaluate the optimal fiscal policies. The motive of status seeking is present as 「relative wealth」 and the wealth is a composite of domestic capital and Foreign Bond. First, we show that when status-seeking motive is present alone in a small open economy, government shall tax the capital accumulation rather than subsidize it. Moreover, we develop that the marginal rate of substitution between consumption and foreign bond plays an important role in determination of government’s optimal taxation.