On the shape of optimal tax schedules

Take consumers to be described by a parameter h (skill, needs, etc.) with utilities defined on N commodities, including factor supplies. Our main result is that if in the optimum each component of this consumption vector is bounded and bounded away from zero over the population, each marginal tax must be zero at both ends of the corresponding tax schedule. For the income tax case, it is also shown that if the marginal tax rate at the top of the scale is positive, one can construct another tax schedule which is strongly Pareto superior (dominating the first one at all or most income levels), requirements of information being low.     

Professor Friedman,meet Lady Rhys-Williams: NIT vs. CIT

In the conventional view, income testing is required to make a tax-transfer program ‘efficient.’ This view can be seen to hinge on the ‘target efficiency’ concept. The economic efficiency of income testing is analyzed here-including distortions of household behavior and the total administrative costs of the tax-transfer system. The income-tested program is a negative income tax system (NIT), which has divergent marginal tax rates for beneficiaries and net taxpayers; the nontested scheme is a credit income tax (CIT), which makes universal payments and imposes a uniform marginal tax rate. Theoretical analysis shows the conditions under which the CIT is more efficient than a comparable NIT. Some suggestive empirical evidence and policy considerations in the choice between NIT and CIT are presented.     

Optimal consumption and the timing of the resolution of uncertainty

As is well-known, consumers want to accumulate precautionary savings in the face of income risks when their marginal utility is convex (prudence). In this paper, we explore the effect of the timing of the resolution of income uncertainty on savings. An agent faces uncertainty about his income at date t+2. What is the effect of being informed that the uncertainty will be resolved at date t+1 on the consumption at date t? We show that the effect is positive, if and only if, marginal utility is convex (prudence), when either the risk free rate is equal to the rate of pure preference for the present, or when the utility function is HARA. The intuition is that an early resolution of uncertainty allows for time-diversifying the risk. It therefore plays a role similar to a reduction of the income risk, whose effect on savings is negative under prudence.     

Donations in a recursive dynamic model

Abstract.  This paper studies how donations respond to unexpected permanent changes in income and tax rates in a recursive dynamic model. The dynamic approach yields several interesting insights. If marginal tax rates are progressive, a permanent jump in a household's income increases its consumption and donations in the short run, but has no effect in the long run. The permanent income elasticity of current donations is likely to exceed one. If the marginal tax rate is flat, the jump in income raises consumption and donations in both the short and the long run. A permanent marginal tax rate cut raises consumption and donations in the long run if marginal tax rates are progressive, while it reduces donations in the short run if it has little direct impact on tax payments. If the marginal tax rate is flat, a tax cut has a positive effect on consumption in both the short and the long run, but has an ambiguous effect on donations.     

Optimal climate and fiscal policy in an OLG economy

This paper develops a climate–economy model to study the joint design of optimal climate and fiscal policies in economies with overlapping generations (OLGs). I demonstrate how capital taxation, if optimal, drives a wedge between the market costs of carbon (the net present value of marginal damages using the market interest rate) and the Pigouvian tax (the net present value of marginal damages using the consumption discount rate of successive OLGs). In contrast to deterministic infinitely lived representative agent models, at the optimum, the capital income tax is positive, the carbon price equals the market costs of carbon but it falls short of the Pigouvian tax when (i) preferences are not separable over consumption and leisure; and (ii) labor income taxes cannot be age-dependent. I also show that restrictions on climate change policy provide a novel rationale for positive capital income taxes.     

When is a tax neutral?

A proportional income tax is said to be neutral if variations in the tax rate do not affect the optimal composition of the consumption commodities of a utility maximizing consumer. It is shown that neutrality obtains if and only if the indirect utility function of the consumer is groupwise homothetic. If the income tax rates on labor and property incomes are allowed to differ, then neutrality obtains if and only if the indirect utility function of the consumer is homothetically separable. If, in addition, it is required that the proportional income tax be neutral with respect to not only consumption commodities but also to leisure, then 'the indirect utility function must have the form: $\text{V = V(f(w)+H}{}^1\text{(p))}$, where w and p are the normalized prices of leisure and consumption respectively, and H¹(p) is homogeneous of degree one in p.     

Linearly progressive income taxes and stabilization

It has been shown that progressive income taxes may lead to saddle-point convergence when the marginal tax rate is assumed to be a continuously increasing function of income. This note shows that linearly progressive taxes may also immunize the economy against indeterminacy and sunspot equilibria. Therefore, our analysis suggests that exemption thresholds, as featured by prevailing tax codes, may help to stabilize the economy.     

INCOME TAXES AND THE COMPOSITION OF PAY: EVIDENCE FROM THE BRITISH HOUSEHOLD PANEL SURVEY

According to the standard principal‐agent model, the optimal composition of pay should balance the provision of incentives with the individual demand for insurance. Do income taxes alter this balance? We show that the relative share of Performance‐related pay (PRP), on total pay is reduced by higher average and marginal income taxes. Empirical evidence based on the British Household Panel Survey is consistent with the theoretical predictions of the tax–augmented principal‐agent model. Our estimates suggest that a 10% reduction in the marginal income tax rate, holding the average tax rate constant, increases the share of PRP in total pay by 2.25–3.02%, depending on the empirical specification. Similarly, a 10% reduction in the average income tax rate, holding the marginal tax rate constant, increases the share of PRP in total pay by 5.10–5.27%.     

Tax Havens,Growth, and Welfare

This paper develops an endogenous growth model featuring tax havens, and uses it to examine how the existence of tax havens affects the economic growth rate and social welfare in high‐tax countries. We show that the presence of tax havens generates two conflicting channels in determining the growth effect. First, the public investment effect states that tax havens may erode tax revenues and in turn decrease the government's infrastructure expenditure, thereby reducing growth. Second, the tax planning effect of tax havens reduces marginal cost of capital and hence encourages capital accumulation so as to spur economic growth. The overall growth effect is ambiguous and is determined by the extent of these two effects. The welfare analysis shows that tax havens are more likely to be welfare‐enhancing if the government expenditure share in production is low, or the initial income tax rate is high. Moreover, the welfare‐maximizing income tax rate is lower than the growth‐maximizing income tax rate if tax havens are present.     

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.     

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.     

Externalities and optimal taxation

This paper reexamines the optimal tax design problem (income and commodities) in the presence of externalities. The nature of the second–best, and the choice of the tax instruments, are motivated by the informational structure in the economy. The main results are: (i) environmental levies (linear or nonlinear) differ in formula from Pigouvian taxes by the expressions for the optimal tax on private goods; (ii) externalities do not affect commodity tax formulas (linear and nonlinear) for private goods; (iii) externalities do not affect the income tax structure if commodity taxes are nonlinear and affect it if commodity taxes are linear; and (iv) a general income tax plus strictly Pigouvian taxes are sufficient for efficient taxation if individuals of different types have identical marginal rates of substitution (at any given consumption bundle).     

Conspicuous consumption and generation replacement in a model of perpetual youth

This paper investigates household decisions in an overlapping generations model in which individual utility depends on a weighted average of consumption of one's peers. In contrast to representative agent economies, the consumption externality generally affects savings and growth rates. The effects critically depend on the rate at which labor productivity changes with age. For a high (low) rate, the externality lowers (raises) the steady state propensity to consume out of total wealth. The optimal allocation can be decentralized by a (reverse) unfunded social security system if the rate of labor productivity decline is high (low). In contrast to discrete time OLG models, the optimal steady state capital income tax is zero, in spite of the externality.     

FBT: How to Structure Remuneration Packages for 1986–87

The purpose of this article is to determine the optimal structure of remuneration packages in the new fringe benefits tax (FBT) environment. We will describe precisely how the optimal structure of remuneration packages depends upon the (marginal) rates of FBT, personal income tax and corporate tax. The fundamental decision rule for employers and employees to optimise the value of remuneration packages is quite simple. First substitute the FBT rate, f, and the employer's marginal tax rate, t, into I = f(1 + f - t)^-1. Then if the employee's marginal tax rate i is greater than I the employer should provide any benefits until i falls to the value I. At or below this point the employee would be better off to provide all subsequent benefits.     

The Enforcement of Income Tax Laws: Efficiency Implications*

Complete enforcement of income tax laws, designed to reduce income tax evasion to zero, is shown to be inefficient. Starting from a 'full compliance' policy, it is shown that a marginal reduction in enforcement will always allow for tax reductions, hence increases in the ex-ante utility levels of taxpayers. Only if the tax structure is rigid can full compliance be optimal.     

The effect of potential emigration on the optimal linear income tax

This paper amends a standard model of optimal linear income taxation to allow individuals to escape taxation by migrating. The income tax is used only to redistribute income in this model. It is found that, if individuals with low and high ability levels are prevented from migrating, then the optimal marginal tax and poll subsidy increase. But preventing migration at ability levels in some intermediate interval lowers the optimal marginal tax.     

Household bargaining and the design of couples’ income taxation

This paper studies the design of couples’ income taxation when consumption and labor supply decisions within the couple are made by maximizing a weighted sum of the spouses’ utilities; bargaining weights are given but specific to each couple. Information structure and labor supply decisions follow the Mirrleesian tradition. However, while the household's total consumption is publicly observable, the consumption levels of the individual spouses are not observable. With a utilitarian social welfare function we show that the expression for a spouses’ marginal income tax rate includes a “Pigouvian” (paternalistic) and an incentive term. The Pigouvian term favors a marginal subsidy (tax) for the high-weight (low-weight) spouse, whose labor supply otherwise tends to be too low (high). The sign and the magnitude of the incentive term depends on the weight structure across couples. In some cases both terms have the same sign and imply a positive marginal tax for the low-weight spouse (who may be female) and a negative one for the high-weight spouse (possibly the male). This is at odds with the traditional Boskin and Sheshinski results. Our conclusions can easily be generalized to more egalitarian welfare functions. Finally, we present numerical simulations based on a calibrated specification of our model. The calculations confirm that the male spouse may well have the lower (and possibly even negative) marginal tax rate.     

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。     

THE IMPACT OF TAX PRICE CHANGES ON CHARITABLE CONTRIBUTIONS TO THE NEEDY

Eliminating or reducing the federal charitable deduction can have serious impacts on the level of charitable donations. Tax price elasticity estimates from a multivariate sample selection model indicate that changing the deduction to a 12% tax credit would have reduced individual donations in 2012 by 18.9% if applied to itemizing taxpayers and by 10.5% if extended to nonitemizers. Elimination of the deduction would have led to a 35% reduction in individual charitable donations. Even if coupled with cuts in marginal tax rates, eliminating the charitable deduction will still likely result in substantial reductions given the inelastic income elasticities of charitable donations. The estimates justify the ardent opposition of many in the nonprofit sector to the more radical proposals for changing the tax treatment of charitable contributions. (JEL D34, C34)     

Optimal Income Taxation with Risky Earnings: A Synthesis

We study optimal nonlinear income taxation when earnings can differ because of both ability and luck, so the income tax has both a redistributive role and an insurance role. A substantial literature on optimal redistribution in the absence of risk has evolved since Mirrlees's original contribution. The literature on the income tax as a social insurance device is more limited. It has largely assumed that households are ex ante identical so unequal earnings are due to risk alone. We provide a general treatment of the optimal income tax under risk when households differ in ability. We characterize optimal marginal tax rates and interpret them in terms of redistribution, insurance, and incentive effects. The case of ex ante identical households and the no‐risk case with heterogeneous abilities come out as special cases.