Optimal Age-Specific Income Taxation

This paper studies optimal earnings taxation in a three‐period life‐cycle model where taxes can be differentiated according to age. Agents choose their level of education when young and their retirement age when old. I study the problem both without and with borrowing constraints. It is shown that, without borrowing constraints, a first‐best optimum can be decentralized by setting a zero tax rate in the third period and a first‐period tax lower than the second‐period one. With borrowing constraints, the first best can no longer be achieved. The gap between the first‐ and second‐period tax rates is larger, while the third‐period tax rate is generally different from zero.     

Optimal Taxation of Risky Human Capital*

In a two‐period life‐cycle model with ex ante homogeneous households, earnings risk, and a general earnings function, we derive the optimal linear labor tax rate and optimal linear education subsidies. The optimal income tax trades off social insurance against incentives to work. Education subsidies are not used for social insurance, but they are only targeted at offsetting the distortions of the labor tax and internalizing a fiscal externality. Both optimal education subsidies and tax rates increase if labor and education are more complementary, because education subsidies indirectly lower labor tax distortions by stimulating labor supply. Optimal education subsidies (taxes) also correct non‐tax distortions arising from missing insurance markets. Education subsidies internalize a positive (negative) fiscal externality if there is underinvestment (overinvestment) in education because of risk. Education policy unambiguously allows for more social insurance if education is a risky activity. However, if education hedges against labor‐market risk, optimal tax rates could be lower than in the case without education subsidies.     

Optimal Nonlinear Income Taxation with Habit Formation

It has recently been shown that incorporating “keeping up with the Joneses” preferences into a prototypical two‐ability‐type optimal nonlinear income tax model leads to higher marginal tax rates for both types of agents. In particular, the high‐skill type faces a positive marginal tax rate, rather than zero as in the conventional case. In this paper, agents’ utility functions are postulated to exhibit “habit formation in consumption” such that the prototypical two‐ability‐type optimal nonlinear income tax model becomes a dynamic analytical framework. We show that if the government can commit to its future fiscal policy, the presence of consumption habits does not affect the standard results on optimal marginal tax rates. By contrast, if the government cannot precommit, the high‐skill type will face a negative marginal tax rate, while the low‐skill type’s marginal tax rate remains positive.     

Optimal Income Taxation with Endogenous Human Capital

This paper augments the theory of optimal linear income taxation by taking into account human capital accumulation as a dimension of labor supply. The distribution of earning potentials is endogenous because agents differ in the ability to learn. Taxation affects utilization rates of human capital through labor supply responses. The costs of education that are not deductible from the income tax distort the learning decision as well. We show theoretically that the trade‐off between efficiency and equity is worsened. Quantitative analysis shows that the distortionary costs of taxation increase substantially when human capital formation is endogenous.     

Optimal Piecewise Linear Income Taxation

Given its significance in practice, piecewise linear taxation has received relatively little attention in the literature. This paper offers a simple and transparent analysis of its main characteristics. We fully characterize optimal tax parameters for the cases in which budget sets are convex and nonconvex respectively. A numerical analysis of a discrete version of the model shows the circumstances under which each of these cases will hold as a global optimum. We find that, given plausible parameter values and wage distributions, the globally optimal tax system is convex, and marginal rate progressivity increases with rising inequality.     

Optimal Social Insurance with Linear Income Taxation*

We study optimal social insurance aimed at insuring disability risk in the presence of linear income taxation. Optimal disability insurance benefits rise with previous earnings. Optimal insurance is incomplete even though disability risks are exogenous and verifiable so that moral hazard in disability insurance is absent. Imperfect insurance is optimal because it encourages workers to insure themselves against disability by working and saving more, thereby alleviating the distortionary impact of the redistributive income tax on labor supply and savings.     

Budget Balancedness and Optimal Income Taxation

We make two contributions to the theory of optimal income taxation. First, assuming conditions sufficient for existence of a Pareto optimal income tax and public goods mechanism, we show that if agents' preferences satisfy an extended notion of single crossing called capacity constrained single crossing, then there exists a Pareto optimal income tax and public goods mechanism that is budget balancing. Second, we show that, even without capacity constrained single crossing, existence of a budget balancing Pareto optimal income tax and public goods mechanism is guaranteed if the set of agent types contains no atoms.     

Taxation of Labor Income and the Demand for Risky Assets

This article analyzes the effect of labor income risk on the joint saving/portfolio-composition problem. Given decreasing absolute prudence, we find that even when labor income risk increases overall saving, it tends to lower investment in a risky asset. Applying the theory to public finance, we argue that realistic increases in marginal tax rates on labor can cause large enough reductions in after-tax labor income risk to cause significant increases in risky investment.     

Optimal Income Taxation and Job Choice

In this paper, we study optimal income taxation when different job types exist for workers of different skills. Each job type has some feasible range of incomes from which workers choose by varying labor supply. Workers are more productive than others in the jobs that suit them best. The model combines features of the classic optimal tax literature with labor variability along the intensive margin, with the extensive‐margin approach where workers make discrete job choices and/or participation decisions. We find that first‐best maximin utility can be achieved in the second‐best, and marginal tax rates below the top can be negative or zero.     

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     

Optimal Income Taxation and International Labour Mobility

This paper considers how a linear income tax should be set optimally when individuals are internationally mobile. The optimum tax analysis is founded on a social welfare function where each individual counts in the social welfare according to residence time in the home country. The discussion of the optimal income tax is organized from two perspectives. The first relates to the optimum income tax when a uniform lump sum transfer is used, while the second concerns the optimal rate of tax when a transfer is used which depends on time of residence in the taxing jurisdiction.     

Optimal Taxation of International Income Flows*

Double taxation of international income flows has been regarded as undesirable and international tax agreements have been negotiated to avoid it. The questions asked are whether double taxation is appropriate and whether cooperation is required to reach the optimal solution. The results are that generally some double taxation is desirable, as long as taxes are applied at the appropriate rates, and that an efficient solution can be attained in the absence of explicit cooperation using a deduction rule, instead of the now commonly used credit rule. A rationale for the current system of tax agreements and their emphasis of the credit rule is discussed.     

Optimal Nonlinear Income Taxation and Heterogeneous Preferences

An attempt is made to find a nonlinear optimal income taxation structure for the Japanese income taxation system, assuming that individuals have heterogeneous preferences between income and leisure. Attention is paid to the horizontal equity considerations and the implications for income as distinguished between skilled and unskilled labour.
JEL Classification Numbers: H20, H55, I31.     

Optimal Income Taxation With Quasi-Linear Preferences Revisited

Properties of the optimal income tax for quasi-linear in leisure preferences are studied. With utilitarian or maxi-min objectives, closed-form solutions are obtained. Bunching occurs over intervals where the second-order incentive condition is binding. Whether this occurs depends solely on the skill distribution. The patterns of consumption and tax rates in the nonbunched range are independent of whether the second-order incentive constraints are binding. Bunching at the bottom can also occur if a non-negative constraint on incomes is binding for some households. The pattern of marginal tax rates depends on the skill distribution and whether it is truncated.     

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.     

Age‐related Optimal Income Taxation*

In most countries, average income varies with age. In this paper we investigate if and how it is possible to enhance the redistributive mechanism by relating tax payments to age. Using an OLG model where some individuals are low skilled all their life while others are low skilled when young but high skilled when old, we first show how an age dependent optimal income tax can Pareto improve upon an age independent income tax. We then characterize the optimal age dependent income tax. A tax on interest income is part of the optimal tax structure.     

Optimal Redistributive Income Taxation and Efficiency Wages*

In this paper, we integrate efficiency wage setting with the theory of optimal redistributive income taxation. In doing so, we use a model with two skill types, where efficiency wage setting characterizes the labor market faced by the low‐skilled, whereas the high‐skilled face a conventional, competitive labor market. We show that the marginal income tax implemented for the high‐skilled is negative under plausible assumptions. The marginal income tax facing the low‐skilled can be either positive or negative, in general. An increase in unemployment benefits contributes to a relaxation of the binding self‐selection constraint, which makes this instrument particularly useful from the perspective of redistribution.     

最优税收、经济增长和收入不公

1.引言在传统的公共财政文献(马斯格雷夫,1959)中,财政有三个公认的职能:(1)提供公共产品和服务;(2)收入再分配;(3)稳定经济。政府预算作为一种稳定工具来使用,在很大程度上是出于时髦的考虑,货币政策已经替代了它所发挥的作用。政府主要致力于提供公共消费和投资以及进行收入再分配。     

Optimal Income Taxation and Public Good Provision with Endogenous Interest Groups

This paper studies public goods provision when agents differ in earning abilities as well as preferences. Heterogeneity in skills makes redistribution desirable and generates an equity-efficiency trade-off. If tax revenues are devoted to a public good, this trade-off is affected in such a way that income transfers are less desirable. High-skilled individuals thus have an incentive to exaggerate their preferences for public goods. Analogously, low-skilled individuals lobby against public good provision. A requirement of collective incentive compatibility eliminates these biases. It implies that income transfers are increased whenever a public good is provided and are decreased otherwise.     

Optimal Factor Income Taxation in the Presence of Unemployment

According to conventional wisdom internationally mobile capital should not be taxed or should be taxed at a lower rate than labour. An important underlying assumption behind this view is that there are no market imperfections, in particular that labour markets clear competitively. At least for Europe, which has been suffering from high unemployment for a long time, this assumption does not seem appropriate. This paper studies the optimal factor taxation in the presence of unemployment which results from the union-firm wage bargaining both with optimal and restricted profit taxation when capital is internationally mobile and labour immobile. In setting tax rates the government is assumed to behave as a Stackelberg leader towards the private sector playing a Nash game. The main conclusion is that in the presence of unemployment, the conventional wisdom turns on its head; capital should generally be taxed at a higher rate than labour.