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.     

Location decisions of a polluting firm and the time consistency of environmental policy

This paper considers location decisions of a monopolist, who faces a tax on its emissions in the home country, under ex post that is, time consistent, and ex ante, that is precommitment, environmental policies. We show that the monopolist will relocate more often under ex post optimal emission taxes. A government which cannot commit to an ex ante emission tax and sets its tax ex post after abatement effort has been chosen, is unable to affect the monopolist’s location decision, because it cannot commit to strategically reduce its tax level in the first stage. Domestic welfare is often higher under ex post emission taxes whenever the monopolist relocates under both policy regimes. Otherwise, welfare is higher under government commitment to an ex ante emission tax level. Thus, government commitment to a policy is not always welfare improving.     

On the Optimality of Search Matching Equilibrium When Workers Are Risk Averse

This paper revisits the normative properties of search‐matching economies when homogeneous workers have concave utility functions and wages are bargained over. The optimal allocation of resources is characterized first when information is perfect and second when search effort is not observable. In the former case, employees should be unable to extract a rent. The optimal marginal tax rate is then 100%. As search effort becomes unobservable, an appropriate positive rent is needed and the optimal marginal tax rate is lower. Moreover, the pretax wage is lower in order to boost labor demand. Finally, in both cases, nonlinear income taxation is a key complement to unemployment insurance.     

The Time‐Consistent Public Goods Provision

In this study, we reconsider the optimal nonlinear tax problem with the public good from the perspective of the commitment issue and examine how it affects the condition of the public good provision. We show that the Samuelson rule should be modified when the government cannot commit and the skill types of taxpayers are revealed in the first period. This is true even if the preference of the taxpayers is separable and additive with respect to consumption and leisure. Our analysis also shows how the lack of commitment affects the formula of the marginal cost of public funds and the level of public good provision. Our findings imply that the level of the public good may be excessive in comparison to the case where the government can commit to its tax policy.     

Optimal tax progressivity in unionised labour markets: What are the driving forces?

In labour markets with collective wage bargaining higher progressivity of the labour income tax creates a trade-off. On the one hand, wages are lowered and unemployment decreases, on the other hand, the individual labour supply decision is distorted at the hours-of-work margin. The optimal level of tax progressivity within this trade-off is determined using a numerical general equilibrium model with imperfect competition on the goods market, collective wage bargaining and a labour-supply module calibrated to empirically plausible elasticity values. The model is calibrated to macroeconomic and institutional parameters of both the OECD average and a number of individual OECD countries. In most cases the optimal degree of tax progressivity is below the actual level. A decomposition approach shows that the optimal level is increased by high unemployment and by the general tax level.     

Optimal income taxation with tax avoidance and endogenous labour supply

I determine the optimal income tax schedule when individuals both choose endogenously their labour supply and have the possibility of avoiding paying taxes. Considering a convex concealment cost function, I propose a formula for the optimal marginal tax rate, that generalizes the formula of the standard Mirrlees model to the case of tax avoidance. I also show that the results obtained by Casamatta (2021) in the fixed income case hold true when labour supply is endogenous: with a low enough marginal cost of avoidance, it is optimal to let some taxpayers, located in the interior of the skill distribution, avoid taxes.     

The effect of taxation on labour supply: the case of moonlighting

The authors provide a simple test of supply-side economics by estimating the responsiveness of moonlighting labour supply to changes in the marginal tax rate and the wage rate. While standard theory teachers that changes in taxes and wage should have opposite and equal effects on labour supply, taxes affect the entire asset position of the household. In the short run, an adjustment of hours in the second job may be the only option available to an individual in responding to a tax change. Thus, analyses based on after-tax wages may understate supply-side effects. To estimate these effects a tobit procedure is employed. The empirical results suggest a backward-bending supply curve over thet range of moonlighting hours. Data consist of a subsample of male blue-collar workers from the 1978 cross-section of the Panel study of Income Dynamics.     

The credibility of commitment and optimal nonlinear savings taxation

Previous studies that examine optimal nonlinear taxation of savings/capital have assumed either full-commitment or no-commitment by the government. This raises the question as to whether the results under full-commitment and no-commitment provide upper and lower bounds on the optimal marginal savings tax rates. This paper shows that they do not. Specifically, we consider an infinite-horizon overlapping generations model in which agents attach some probability to whether or not the government can commit. When these probabilistic beliefs differ among high-skill individuals, the optimal steady-state marginal savings tax rates may fall outside those under the polar cases of full-commitment and no-commitment. Our numerical analysis finds that this theoretical possibility can occur under a baseline calibration with empirically plausible values of model parameters, and that it remains qualitatively robust with respect to various parametric changes.     

Macroeconomic Policy to Aid Recovery after Social Distancing for COVID-19

Using the Keynesian model set out in McDonald (2020), in which downward wage rigidity is supported by worker loss aversion with respect to wages, this article shows that a period of social distancing (SD) can leave a post-SD economy with both stimulatory and depressive effects. A loss of productive capacity is stimulating. Costs of restarting firms, lower labour productivity when restarted and a desire to restore wealth from debt incurred during the period of SD are depressive. If, as seems highly probable, the net effect on economic activity is negative then a fiscal expansion can restore activity. To avoid an increased government budget deficit, this expansion would probably require an increased tax rate. Reductions in real wages may also be necessary. A desire to balance the government budget combined with no increase in the tax rate would be unfortunate, because it would cause a further contraction in activity from its post-SD level.     

Education, Work and Wages in the UK

Abstract. This paper is concerned with the relationship between education, wages and working behaviour. The work is partly motivated by the sharp distinction in the literature between the returns to education and the effect of wages on labour supply. Education is the investment that cumulates in the form of human capital while labour supply is the utilization rate of that stock. Yet, variation in education is usually the basis for identifying labour supply models – education is assumed to determine wages but not affect labour supply. Moreover, it is commonly assumed that the private rate of return to education can be found from the schooling coefficient in a log-wage equation. Yet, the costs of education are largely independent of its subsequent utilization but the benefits will be higher the greater the utilization rate. Thus the returns will depend on how intensively that capital is utilized and we would expect that those who intend to work least to also invest least in human capital. Indeed, the net (of tax liabilities and welfare entitlements) return to education will be a complex function of labour supply and budget constraint considerations.
Here we attempt to model the relationship between wages, work, education and the tax/welfare system allowing for the endogeneity of education as well for the correlations between the unobservable components of wages and working behaviour. We use the estimates to simulate the effect of a new UK policy designed to increase education for children from low-income households.     

Wage endogeneity,tax evasion,and optimal nonlinear income taxation

This paper studies the interaction between tax evasion and wage endogeneity within a Mirrleesian optimal tax framework. It characterizes the optimal marginal income tax rates on the skilled and the unskilled workers and the optimal amount of resources to be spent on deterring tax evasion. It shows that tax evasion weakens the incentives for the government to manipulate the marginal tax rates for the purpose of exploiting general equilibrium effects on wages. Moreover, the extent of this depends on the curvature of the evasion cost function. It also argues that marginal income tax rates are likely to be higher when the government attempts to deter evasion.     

Taxation of firms with unknown mobility

We analyze optimal business tax policy when some firms are able to escape taxation by moving abroad. In contrast to the existing literature, we assume that the true number of mobile firms is ex ante unknown. While the government may learn from the firms' location responses to past tax rate changes, firms may anticipate this and adjust their choices accordingly. We find that incomplete information on mobility substantially affects the properties and the implications of equilibrium policy choices. First, the government may find it optimal to set a tax rate that triggers partial firm migration but full revelation of the true number of mobile firms. Second, we show that, if the firms' outside option is attractive (i.e., relocation cost and foreign tax rates are low), expected tax rates and expected firm migration are higher if the degree of mobility is unknown. Third, there is a positive value of learning, i.e., commitment on future tax rates cannot increase the government's expected revenue. However, if the government can commit to a rule‐based learning mechanism, i.e., credibly tie its future tax policy to present policy outcomes, it may obtain a Pareto improvement.     

Environmental Policy, Tax Incidence, and the Cost of Public Funds

This paper studies under what conditions a double dividend may occur in the sense that both environmental quality and employment rise. A simple static general equilibrium model is employed in which tax policy faces the dual task of internalising a negative environmental externality and raising revenue to finance public consumption. The model features a clearing labour market with both labour demand and supply and a fixed factor of production (e.g. capital). Hence, we can study tax incidence and its effect on employment, environmental quality, and the marginal cost of public funds. It is shown for the case of an upward sloping labour supply curve and less than full tax shifting by employers that a shift towards greener preferences cannot yield a double dividend, even if the fixed factor is important. However, if labour supply curve bends backwards, more environmental concern confers a double dividend.     

Time-Consistent Public Policy

In this paper we study how a benevolent government that cannot commit to future policy should trade off the costs and benefits of public expenditure. We characterize and solve for Markov-perfect equilibria of the dynamic game between successive governments. The characterization consists of an inter-temporal first-order condition (a "generalized Euler equation") for the government, and we use it both to gain insight into the nature of the equilibrium and as a basis for computations. For a calibrated economy, we find that when the only tax base available to the government is capital income—an inelastic source of funds at any point in time—the government still refrains from taxing at confiscatory rates. We also find that when the only tax base is labour income the Markov equilibrium features less public expenditure and lower tax rates than the Ramsey equilibrium.     

Transport Taxes with Multiple Trip Purposes

A congestible urban transport system is considered in which cars and buses are used for commuting and non‐commuting trips. Commuting is a strict complement to taxable labour supply. The optimal tax structure for raising a given amount of government revenue is examined for the cases where differentiation of transport tolls between trip purposes is and is not possible. An application to Belgian urban environments shows that optimal toll differentiation produces significant efficiency improvements. Without differentiation, reforming transport taxes generates substantial gains only when the labour tax can be reduced.     

Evaluation of Policy Options to Encourage Welfare to Work

This article compares five alternative policy options with the January 2006 tax and social security system. Each option is designed to cost a similar amount of approximately $5 billion per year to the government at the observed level of labour supply. The five options include reducing the lowest income tax rate, increasing the tax‐free threshold, increasing the low income tax offset, decreasing all taper rates on own and partner's incomes for a number of allowances, and introducing an earned income tax credit. The criteria for comparison are the labour supply responses, the expected budgetary cost to the government after taking into account labour supply responses, the number of winners and losers from the policy change, the effects on the distribution of effective marginal tax rates, and the effects on the number of jobless households. From the results, it is clear that the option to reduce taper rates is dominated by the other options on all criteria. The other four options each have their advantages and disadvantages; no option scores best on all criteria.     

Reconsidering the Marginal Welfare Cost of Taxation*

A model with sticky wage rates and involuntary unemployment is used to compute the marginal cost of taxation, and these estimates are compared with those obtained from the conventional price-clearing equilibrium model. Important determinants of the marginal cost estimates are the response of sticky wages to a tax increase, the elasticity of demand for labour, and the unemployment gap. By contrast, the conventional model focuses on the elasticity of labour supply. The different models have different implications for efficient tax design. However, the new model generally agrees with the conventional model regarding significant efficiency costs of higher taxation.     

Optimal income taxation with a stationarity constraint in a dynamic stochastic economy

We consider the optimal nonlinear income taxation problem in a dynamic, stochastic environment when the government cannot change the tax rule as uncertainty resolves. Due to such a stationarity constraint, our taxation problem is reduced to a static one over an expanded type space that incorporates type evolution. We strengthen the argument in the static model that the zero top marginal tax rate result is of little practical importance because it only applies to the top of the expanded type space. If the maximal type increases over time, the person with top ability in any period but the last has a positive marginal tax rate.     

Public investment criteria under optimal nonlinear income taxation without commitment

In this study, we highlight that the incredibility of the government's commitment to a certain tax policy is a determinant of production inefficiency. We show that if the government cannot commit to a certain tax policy and if the types of taxpayers are completely separated, then the production efficiency theorem could be violated in an optimal solution. In this case, an incremental unit of public or private capital affects taxpayers' labor supply through wage rates. In a situation where public capital is more (less) complementary to labor than private capital, public investment tightens (relaxes) the incentive compatibility constraint more than private investment.