Optimal income taxation and migration: a world welfare point of view

This paper considers a world in which a distortionary income tax must be employed to raise and redistribute revenue. The optimal taxation of emigrants relative to those left behind is examined under the objective of world social welfare maximization. When tastes for consumption and labor do not depend directly on residence, the optimal tax system induces individuals to reside where the marginal products of their chosen labor supplies are highest. This paper also proves the existence of an optimal tax system under which each individual resides where he pays the greatest tax. This result holds even when tastes are allowed to vary with residence in an interesting way.     

Optimal Capital Income Taxation with Means‐tested Benefits

This paper studies the interaction between capital income taxation and a means‐tested age pension. Our results document that the existence of a social insurance program financed from general revenue puts an upward pressure on the optimal tax rate. We also show that there is a negative relation between taper (benefit‐reduction) and optimal capital income tax rates. The potential welfare gain from optimizing capital taxation in the presence of a universal retirement transfer system is relatively higher. However, when the transfer is substantially means tested, the gain is lower, because the means test effectively operates as a tax on retirement capital.     

Is commodity taxation unfair?

In a model where agents have unequal skills and heterogeneous preferences about consumption goods and leisure, this paper studies how to combine commodity taxes and non-linear income tax. It proposes a particular social welfare function on the basis of fairness principles. It then derives a simple criterion for evaluating the social welfare consequences of various tax schedules. Under the proposed approach, the optimal tax should have no commodity tax for some range of consumptions, and income redistribution would feature high subsidies to the working poor. It is also shown that, even when the income tax fails to be optimal, commodity taxes may not improve social welfare.     

Numerical simulation on property tax reform: evidence from China

This article analyses the property tax reform in China in a computable general equilibrium model that recognizes the interaction between and among housing markets in different provinces and macroeconomic development. Using real data in 2010, we present the benchmark equilibrium for reference property and income tax rates. Then, we examine different property and income tax policies and make a comparison of their production, consumption, welfare and national income. We find that the implementation of property tax would decrease the house production at the expense of welfare in taxed area. The expansion of the taxed regions may increase the total social welfare and national income. Even though property tax policy may not be able to change the income distribution in China, increasing income tax rate could narrow the income disparity. Finally, this article shows the reliability of the conclusions when sensitivity analysis on optimal condition of equilibrium computation is performed under varied property tax policy.     

Optimal Taxation with a Trade-off Between Income and Children

This paper explores the implications of endogenous fertility for optimal redistributive taxation in the presence of a trade-off between labour income and children. The labour supply is a decreasing function of the desired quantity and quality of children. Since children enter into the parent's budget constraint in a nonlinear form, their shadow prices are directly distorted by the income tax rate. It is shown that the substitution effects of the income tax rate on the quantity and quality of children cannot be signed uniquely although the effect on labour supply is negative. The aggregate substitution effect of the income tax rate on the quantity of children plays an important role in the determination of the signs of the income tax and child subsidy rates at a Rawlsian or Benthamite social welfare optimum.
JEL Classification Numbers: H21, J13, J22     

The Optimal Linear Income Tax Model: Utility or Equivalent Income?

This paper compares the use of equivalent income with that of utility, in the social welfare function, in optimal income tax models. Equivalent income is a money metric welfare measure that, unlike utility, is not affected by monotonic transformations of utility. The use of equivalent income is found to produce an optimal tax rate that is more sensitive to the degree of inequality aversion, compared with the use of utility. With Cobb-Douglas and CES utility functions, the optimal tax rate is the same for utility and equivalent income where relative inequality aversion is unity. When using equivalent incomes, the case for high marginal rates does not depend on the assumption of a very low elasticity of substitution between consumption and leisure.     

Capital income taxation,tax criteria,and intergenerational welfare

In a two-period overlapping-generations model, residence criteria are shown to be optimal with lump-sum transfers to the younger generation in a dynamically efficient open economy even if all wage income, corresponding to rent income under exogenous labor supply, is not taxed away. When tax revenues are also distributed to the older generation — which indeed may be desirable for short-term intergenerational welfare distribution reasons — a weighted average rule is derived for optimal international taxation. The taxation of domestic savings income follows the inverse elasticity rule in respect to savings and, surprisingly, higher investment elasticity increases the tax level. Finally, for a small open economy and for large identical economies, tax competition with a mixed scheme of residence-based taxes and source-based subsidies yields the same tax policy as tax cooperation with no restrictions on the domestic and international capital income tax instruments.     

AN APPROXIMATION FOR THE OPTIMAL LINEAR INCOME TAX RATE

This paper derives a convenient method of calculating an approximation to the optimal tax rate in a linear income tax structure. Individuals are assumed to have Cobb-Douglas preferences and the wage rate distribution is lognormal. First, the optimal tax rate is shown, for a general form of social welfare function, to be the smallest root of a quadratic equation involving a welfare-weighted average wage rate. Second, an approximation to this average is derived for an isoelastic social welfare function. This average depends on the degree of inequality aversion of the welfare function and the coefficient on consumption in individuals' utility functions. Calculations show that the method performs well in comparison with standard simulation methods of computing the optimal tax rate.     

Optimal Thin Capitalisation Rule in a Simple Endogenous Growth Model with Tax Havens

In this paper we study the optimal thin capitalisation rules by developing a simple dynamic general‐equilibrium growth model incorporating tax havens. It is found that a stricter thin capitalisation rule will reduce the incentive to invest, and is therefore harmful to growth. This effect is ignored in previous static studies on the welfare analysis of tax havens. Accordingly, when taking the growth effect into consideration, reducing the utilisation of tax havens has ambiguous effects on social welfare. We also show that a looser thin capitalisation rule could be favourable for the policymakers if (i) the production technology is high; (ii) the existing income tax rate is high; (iii) the rate of time preference is low; or (iv) the weight factor of public consumption in utility is small.     

Optimal fiscal policy in an endogenous growth model with public capital: a note

This note presents an investigation of the optimal tax rule in endogenous growth models with public capital. It is presumed that the government levies only an income tax in addition to financing public investment. Furthermore, a household’s saving is deducted from the income tax. We find the optimal tax rule whereby the social optimum is attainable. The manner by which a government imposes a tax on income and administers tax deductions is important for attaining a socially optimal situation.      

效率与公平兼顾的最优所得税:理论框架及最优税率估计

最优所得税主要探讨税收如何兼顾公平与效率问题,以及给定公平偏好程度下,如何确定最优边际税率水平。即使在崇尚罗尔斯社会福利函数的社会里,政府同时兼顾再分配和财政收入目标的基础上,只要略加考虑税收对劳动供给的效应,哪怕是微弱的考虑和兼顾,最高边际税率都不会达到100%。而且,借鉴斯特恩最优线性所得税模型及美国个人所得税制度,估计我国现行个人所得税最高边际税率还可以适当降低到36%左右。     

Time-consistent taxation in a dynastic family model with human and physical capital and a balanced government budget

Abstract .  This paper analyzes optimal, time consistent taxation in a dynastic family model with human and physical capital and with a balanced government budget. When tax revenue is used for publicly provided consumption or lump-sum transfers, leisure would be higher than its social optimum. Pareto optimal taxation requires taxing capital income more heavily than labour income and subsidizing investment at the same rate of the tax. Also, it requires either subsidizing labour at the same rate as a consumption tax or subsidizing consumption at the same rate as a labour income tax, and hence it is not a practical guide to policy. Further, a consumption tax, or equivalently a uniform income tax with investment subsidies at the same rate, can be improved on by taxing capital income more heavily than labour income.     

Optimum income taxation and layoff taxes

This paper analyzes optimum income taxation in a model with endogenous job destruction that gives rise to unemployment. It is shown that optimal tax schemes comprise both payroll and layoff taxes when the state provides public unemployment insurance and aims at redistributing income. The optimal layoff tax is equal to the social cost of job destruction, which amounts to the sum of unemployment benefits (that the state pays to unemployed workers) and payroll taxes (that the state does not get when workers are unemployed).     

Asymptotic Marginal Tax Rate of Individual Income Tax in China

This paper examines the asymptotic marginal rate of individual income tax which maximizes China's social welfare through numerical simulation based on the elasticity of China's labor supply, income distribution and the social objectives of redistribution in accordance with the optimal direct taxation theory. Taking advantage of the optimal direct taxation model with consideration of the income effect, it comes to the conclusion that combined with China's reality, the asymptotic marginal rate of individual labor income tax in China should be between 35% and 40%.     

Are Higher Education Subsidies Second Best?

An optimal taxation framework is considered in which part of the population can take advantage of investment in higher education. It is shown that social welfare can sometimes be increased by supplementing linear income taxes with a subsidy to material investment in higher education, but that social welfare can never be increased by supplementing a non‐linear income tax with such a subsidy.     

Optimal Redistribution with Heterogeneous Preferences for Leisure

This paper examines the properties of the optimal nonlinear income tax when preferences are quasi–linear in leisure and individuals differ in their ability and their preferences for leisure. The government seeks to redistribute income. It can perfectly observe the level of endogenous income but cannot observe either ability or preferences. The heterogeneity of preferences leads to problems of comparability between individual utilities which challenge the design of redistributive schemes. We analyze the consequences of adopting a utilitarian social welfare function where the government is allowed to give different weights to individuals with different preferences. Under this particular social objective and given the quasi–linearity of preferences, we are able to obtain closed–form solutions for the marginal tax rates and to examine the progressivity of the tax system according to the weights used.     

社会保障税与社会保障制度优化

社会保障税是指定用于社会保障的工薪税。本文分析了工薪税的税收归宿和劳动供给弹性的影响。当劳动供给弹性较小时 ,税收主要由劳动力负担 ,而且可能会增加就业压力 ;工薪税在劳动同质程度较高时可以取得较好的再分配效应。本文还描述了社会保障制度优化的理论过程。社会保障制度优化是指现收现付计划和强制储蓄计划的最优搭配 ,它以“黄金律”条件下的隔代帕累托改进为标准。就同代收入再分配而言 ,将收入再分配计划的目标定为提高受益人的受教育水平 ,而不是直接为其提供免费的社会福利 ,将有助于缓解收入再分配的代价。     

Higher Tax for Top Earners

The literature can justify both increasing and decreasing marginal taxes (IMT & DMT) on top incomes under different welfare objectives and income distributions. Even when DMT are theoretically optimal, they are often politically infeasible. Then a flat tax seems to be a constrained optimal solution. We show however that, given any flat tax we can increase the total utility of a poor majority by raising the top income tax rate under a simple condition, which can be checked with empirical data. We further generalize our main results allowing different welfare weights, declining elasticity of labor supply and more tax bands.     

Optimal welfare and in-work benefits with search unemployment and observable abilities

This paper explores the optimal interaction between the tax system and social assistance in insuring people against the risks of involuntary unemployment and low ability. To that end, we introduce search unemployment in a model of optimal non-linear income taxation. The relationship between welfare benefits and the optimal level of in-work benefits is U-shaped. This explains why in-work benefits are called for both in countries that grant low welfare benefits and countries that provide high welfare benefits. An earned-income tax credit optimally induces all agents to look for work if job search is cheap and effective, agents are not very risk averse, and the least-skilled agents are relatively productive.