【Micro/Public Finance Seminar】Supplementary Commodity Taxes, Labor Tax on the Middle Class, and the Tax-Mix
2026/05/06
研討會日期 : 2026-05-06
時間 : 14:30
主講人 : Professor Yukihiro Nishimura
地點 : Conference Room B110
主持人 : Professor Sung-Ju Wu
演講者簡介 : Dr. Yukihiro Nishimura received his Ph.D. in Economics from Queen's University in 2002. He is currently a Professor at Osaka University. His research interests are Tax Competition, Political Economics, Public Good Provision, Fiscal Federalism, and Optimal Taxation.
演講摘要 : This paper extends the Atkinson–Stiglitz Theorem by relaxing the assumption of weak separability of preferences. We show that, to supplement income taxation, the optimal commodity tax burden relative to disposable income is regressive. This regressivity reinforces the classic U-shaped pattern of optimal labor income taxation. Moreover, when goods are complementary to leisure, the overall marginal labor tax burden increases once commodity taxes are introduced; when they are substitutes, it decreases. Under the Rawlsian objective, these variations in marginal tax rates have stronger effects at lower income levels. Suppose that preferences are partially separable between a subset of goods and labor supply. We show that, in the presence of linear taxation on all goods, a Pareto-improving tax reform toward partially uniform commodity taxation fails to satisfy incentive compatibility. Furthermore, distortions of production that alter relative wages can improve welfare by relaxing incentive compatibility constraints.
