Efficient timing of income taxes

The marginal collection cost of an income tax is predicted to be a martingale, and the marginal income tax rate is predicted to be a supermartingale. Collection costs can be estimated from tax rates. Almost all tests based on a U.S. series of actual marginal income tax rates, 1913–1975, accept the hypothesis of random-walk behavior in collection costs, and reject the parallel hypothesis on tax rates.     

Altruism,jealousy and the theory of optimal non-linear taxation

This paper studies optimal non-linear taxes in a world in which there is altruism and jealousy. A formula for optimal marginal tax rates is derived which turns out to be a simple and intuitively appealing extension of a result due to Mirrlees. The paper shows that in this sort of economy all of optimal tax theory's general results either no longer hold or need not hold, and it sets out appropriate modifications to standard tax rules.     

RELATIVITY,INEQUALITY, AND OPTIMAL NONLINEAR INCOME TAXATION

How does concern for consumption relative to others (“relativity”) affect the structure of optimal nonlinear income taxation? Our article provides three sets of answers to this general question. First, it supports the conclusion in the literature that relativity leads to higher marginal tax rates. In doing so, it both generalizes some of the conditions under which this result is obtained in the literature and fleshes out the detailed structure for optimal marginal tax rates for specific functional forms for distribution, utility function, and social welfare function. Second, the article goes beyond the literature and examines the impact of relativity on the progression of optimal marginal tax rates. By and large, we find support for greater progressivity, defined as the steepness of the rise of the marginal tax rate schedule, as relativity concern increases. Third, none of the papers in the literature, to our knowledge, examines the interplay of relativity and inequality in determining the optimal structure of income taxes. Our special analytical cases and more general numerical calculations support the conclusion that higher inequality dampens the positive impact of greater relativity on the level and the progression of marginal tax rates. More work is needed to further explore this interaction between relativity and inequality that our analysis has uncovered.     

Tax revenue and the marginal cost of public funds in Sweden

We assess the welfare cost of raising a marginal unit of tax revenue in a balanced-budget, general-equilibrium framework. The calculated social cost of an increment of public funds is sensitive to both the specific type of tax increase and the type of public spending used on the margin. ‘Best-guess’ assumptions on labor supply elasticities yield marginal costs of public funds for different fiscal mixes of between 0.67 and 4.51 at prevailing tax rates in Sweden. Alternative labor supply assumptions well within the range of current estimates substantially affect the results and can imply infinite marginal welfare costs. Marginal welfare costs are also sensitive to assumptions about both the income and substitution effects of labor supply.     

Greenhouse Gas Abatement Cost Curves of the Residential Heating Market: A Microeconomic Approach

In this paper, we develop a microeconomic approach to deduce greenhouse gas abatement cost curves of the residential heating sector. Our research is based on a system dynamics microsimulation of private households’ investment decisions for heating systems to the year 2030. By accounting for household-specific characteristics, we investigate the welfare costs of different abatement policies in terms of the compensating variation and the excess burden. We investigate two policies: (i) a carbon tax and (ii) subsidies on heating system investments. We deduce abatement cost curves for both policies by simulating welfare costs and greenhouse gas emissions to the year 2030. We find that (i) welfare-based abatement costs are generally higher than pure technical equipment costs; (ii) given utility maximizing households a carbon tax is the most welfare-efficient policy and; (iii) if households are not utility maximizing, a subsidy on investments may have lower marginal greenhouse gas abatement costs than a carbon tax.     

A many-person Ramsey tax rule

Define the social marginal utility of an individual's income as the gain to society of a unit of consumption by the individual plus the value of his marginal propensity to pay taxes out of income. This concept rather than the social marginal utility of consumption (equal to the first term above) seems helpful in understanding optimal tax first order conditions. For example, with many consumers (and a poll tax as well as excise taxes) the change in aggregate compensated quantity demanded is proportional to the covariance between individual quantities demanded and social marginal utilities of income.     

A Note on Emissions Taxes and Incomplete Information

In contrast with what we perceive is the conventional wisdom about setting a second-best emissions tax to control a uniformly mixed pollutant under uncertainty, we demonstrate that setting a uniform tax equal to expected marginal damage is not generally efficient under incomplete information about firms’ abatement costs and damages from pollution. We show that efficient taxes will deviate from expected marginal damage if marginal damage is increasing and there is uncertainty about the slopes of the marginal abatement costs of regulated firms. Moreover, tax rates will vary across firms if a regulator can use observable firm-level characteristics to gain some information about how the firms’ marginal abatement costs vary.     

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 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 mixed taxation,public goods and the problem of high-skilled emigration

The optimal income tax model under the threat of migration of Simula and Trannoy (J Public Econ 94:163–173, 2010; Soc Choice Welf 39(4):751–782, 2012) is extended to include indirect taxes and public goods. This enables us to conclude that: (1) optimal income tax rates are higher than in the absence of indirect taxation, and may be positive at the top of the skills distribution; (2) indirect taxes, à la Corlett and Hague, may help mitigate the loss of redistributive capacity arising from income taxation caused by migration threats; (3) migration encourages the provision of the public goods preferred by the most productive workers; (4) optimal tax and public goods provision policies against the emigration of the highly-skilled are connected through the conditions for Pareto efficiency; (5) if the number of potential migrators is large, it may be desirable to violate classical tax rules to retain the most able in the home country; (6) when migration costs are exogenously given and utility is weakly separable, Simula and Trannoy’s results are restored; (7) if migration costs are endogenous, the Atkinson and Stiglitz theorem breaks down and the taxation of country-specific goods becomes desirable, even if utility is strongly separable.     

The Collective Household, Household Production and Efficiency of Marginal Reforms

Most research on the welfare properties of taxes employs the unitary model of the household, ignoring household production. A simple model provides expressions for the changes in individual utility given marginal reforms to government policy. It is shown that the burden of a higher tax on household goods falls on the household member that consumes more than they produce or purchase. Numerical calculations show that price substitution (complementarity) between home and market labor increases (decreases) aggregate efficiency costs of a marginal redistribution of income without impacting the intra-household distribution of utility changes. Modeling household goods as public versus private can alter the distributional consequences of marginal reforms.     

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.     

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).     

Migration and optimal income taxes

The issue addressed in this paper is the optimal taxation of incomes earned in the home economy, and of incomes earned abroad, when people can migrate. As a preliminary, the optimal taxation of home incomes when there is migration and no taxation of foreign incomes, is discussed. Then in a more general setting, we deal with optimal taxation of different kinds of labour when another kind of labour is not taxable, and show how this bears on the taxation of foreign incomes. The last sections of the paper analyse a simple model in which people choose between taxable labour at home, taxable labour abroad, and untaxable labour. A condition is found implying that the optimal tax on foreign income is higher than on the home income of a person of equal utility.     

The failure of Ricardian equivalence under progressive wealth taxation

Although the Ricardian Equivalence Theorem holds under a linear estate tax schedule, it fails to hold under a nonlinear estate tax schedule. In a representative consumer economy, a temporary lump-sum tax increase reduces contemporaneous consumption. If different consumers face different marginal estate tax rates because they leave bequests of different sizes, a lump-sum tax increase redistributes resources from consumers in low marginal estate tax brackets to consumers in high marginal estate tax brackets; aggregate consumption may rise, fall, or remain unchanged. These departures from Ricardian Equivalence hold more generally under any nonlinear tax on saving, wealth or income accruing to wealth.     

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.     

Optimal linear income taxation in the presence of emigration

This paper examines optimal linear income taxation when individuals are able to escape taxation by migrating. A model is presented in which closing the economy to migration must raise the optimal marginal tax. However, this result may be reversed under an alternative definition of a closed economy.     

How do market reforms affect China's responsiveness to environmental policy?

A large percentage of total investment in China is allocated by the central government at below-market interest rates in pursuit of non-economic objectives. This has resulted in low rates of return and a high number of non-performing loans, threatening the future health of the Chinese economy. As a result, reform of capital markets is a high priority of the Chinese government. At the same time, the country is implementing various environmental policies to deal with serious pollution issues. In this paper we ask how reforms of the capital market will affect the functioning of a carbon tax. This allows us to assess how China's willingness to join global efforts to reduce carbon emissions is influenced by China's current efforts to reduce investment subsidies. We compare the costs of a carbon tax in a reformed economy with the costs of a carbon tax in the current subsidized economy. We find that in the subsidized economy the tax-interaction effect dampens the effect of a carbon tax resulting in smaller reductions in emissions than what would result in a reformed economy. Importantly, we also find that the effect on economic welfare from a carbon tax is lower in the subsidized economy; in fact, for lower levels of reductions, the carbon tax is actually welfare improving. These results have important implications for an economy undergoing economic transition. The carbon tax rate required to achieve a certain level of emission reductions will be higher in an economy with capital subsidies. However, the welfare implications of the tax indicate that the current system with capital subsidies is highly distorting implying that there is a high efficiency cost for the non-economic objectives the government is pursuing by maintaining this system of subsidies.     

Costly Tax Enforcement and Financial Repression

Using an overlapping generations production‐economy model characterized by financial repression, purposeful government expenditures and cost of tax collection, we analyse whether financial repression can be explained by the cost of raising taxes. We show that with public expenditures affecting utility of the agents, modest costs of tax collection tend to result in financial repression being pursued as an optimal policy by the consolidated government. However, when public expenditures are purposeless, the above result only holds for relatively higher costs of tax collection. But, more importantly, costs of tax collection cannot produce a monotonic increase in the reserve requirements. What are critical, in this regard, are the weights the consumer assigns to the public good in the utility function and the size of the government.     

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.