On Optimal Commodity Taxes When Consumption Is Time Consuming

This paper studies the problem of optimal taxation of commodities when consumption is a time‐consuming activity. This is done under two distinct preference separability assumptions: between goods and labor supply, and between goods and leisure. It argues that with the labor separability, the traditional uniform taxation results of optimal tax theory continue to hold. With leisure separability, on the other hand, consumption time is a major ingredient of optimal tax rates. However, the relationship between consumption time and optimal tax rates depends crucially on the representation of the economy. In representative consumer economies, time differences determine the pattern of optimal tax rates so that goods whose consumption take more time are subjected to higher tax rates. When individuals have different earning abilities, redistributive, incentive, and efficiency considerations also come into play resulting in a complex relationship. The paper derives formulas for optimal commodity taxes in this case on the basis of three different tax structures: linear commodity taxes in combination with linear and nonlinear income taxes, and nonlinear commodity taxes in combination with nonlinear income taxes.     

Relative Consumption Concerns and the Optimal Tax Mix

This paper studies the optimal tax mix (taxes on income and commodities) under asymmetric information in a two‐type model, when individuals make relative consumption comparisons. The model includes both positional and nonpositional goods, taking into account the fact that relative concerns matter for some but not for all commodities. We find that in general the whole tax system is affected by the externalities caused by the consumption of positional goods, notably also the taxes on income and on a nonpositional good. The tax rates on positional goods are higher than in the absence of status effects, reflecting their Pigouvian role. The sign of the Pigouvian part in the income tax schedule is ambiguous and depends crucially on whether status goods are complements or substitutes to leisure.     

Keeping up with the Joneses, consumer ethnocentrism, and optimal taxation

This paper sets up a two-good (domestically- and internationally-produced goods) model of a small open economy with consumption externalities and uses it to examine the optimal taxation. Since keeping up with the Joneses leads an individual consumption's to impose a negative externality on the consumption of others, a consumption tax and tariff are thereby socially desirable to correct this distortion. Due to the fact that the government has to account for additional distortion caused by consumer ethnocentrism and that keeping up with the Joneses in the consumption of domestic goods tends to reinforce the influence of ethnocentrism on the purchase of domestic products, the consumption of imported goods is subject to a higher tariff rate because of the cross-market externality. Of interest, if consumption only involves an own-market externality, there is no cyclical consequence for the optimal taxes. However, if consumption involves both own- and cross-market externalities, the optimal tariff is state-contingent and, more specifically, is countercyclical.     

Trade,environment, and income inequality: An optimal taxation approach

In a small open economy, how should a government pursuing both environmental and redistributive objectives design domestic taxes when redistribution is costly? And how does trade liberalization affect the economy's levels of pollution and inequalities, when taxes are optimally and endogenously adjusted? Using a general equilibrium model under asymmetric information with two goods, two factors (skilled and unskilled labor), and pollution, this paper characterizes the optimal mixed tax system (nonlinear income tax and linear commodity and production taxes/subsidies) with both production and consumption externalities. While optimal income taxes are not directly affected by environmental externalities, conditions are derived under which under‐ or over‐internalization of social marginal damage is optimal for redistributive considerations. Assuming that redistribution operates in favor of the unskilled workers and that the dirty sector is intensive in unskilled labor, simulations suggest that trade liberalization involves a clear trade‐off between the reduction of inequalities and the control of pollution when the source of externality is only production; this is not necessarily true with a consumption externality. Finally, an increase in the willingness to redistribute income toward the unskilled results paradoxically in less pollution and more income inequalities.     

Environmental taxes with heterogeneous consumers: an application to energy consumption in France

This paper constructs a model with four groups of households who have preferences over labor supply, consumption of polluting (energy related) and non-polluting (non-energy) goods, and emissions. It quantifies the model for the French economy and computes its optimal tax equilibria under nine second-best tax regimes. We find that the redistributive role of environmental taxes requires the polluting goods to be taxed at a rate much below their marginal social damage. These goods may even require an outright subsidy if the society values equality ‘a lot’. Secondly, if environmental taxes that have an exclusively externality-correcting role, they benefit all types—although the gains are rather modest. The gains and losses become more substantial when environmental taxes have a redistributive role as well. Third, setting the environmental tax at its Pigouvian level, rather than its optimal externality-correcting-cum-redistributive level, benefits the high-income group at the expense of the low-income groups. Fourth, nonlinear taxation of polluting goods, and nonlinear commodity taxation in general, is a powerful redistributive mechanism. Fifth, introducing environmental taxes in the current French tax system, with its suboptimal income taxes, results in substantial welfare gains for the highest income group and a sizable loss for the least well-off persons.     

Fiscal Constitutions

In this paper we examine how taxes, subsidies and the design of constitutional agendas should be regulated in order to allow for an efficient allocation of public goods and a limitation of tax distortions. We show that if public goods are socially desirable, the simple majority rule, combined with taxation constrained to majority winners or a ban on subsidies, can achieve several desirable objectives. Equal treatment regarding taxes and subsidies is undesirable. Super majority rules and equal treatment of all citizens with respect to taxes and subsidies, however, are first-best provided public goods are socially undesirable. Finally, we suggest that constitutions with amendments eliminate excessive taxation and allow treatment rules to universally improve welfare.     

Second-Best Pollution Taxes: an Analytical Framework and Some New Results

This paper compares the second-best optimal tax on polluting consumption goods with the Pigovian tax, which would internalize marginal environmental damage at a second-best optimum. It is shown that the relationship between the optimal tax on polluting consumption and the Pigovian tax is determined by the substitutability between labour and polluting consumption or clean and polluting consumption, depending on whether a wage tax system or a commodity tax system is being considered. The key factor determining the relationship between the two taxes is gross substitutability between the two taxed goods. As long as there is gross substitutability, the optimal dirt tax exceeds the Pigovian tax. The opposite can occur if and only if the two goods are gross complements.     

Nonseparable preferences and optimal social security systems

In this paper, we consider economies in which agents are privately informed about their skills, which evolve stochastically over time. We require agents' preferences to be weakly separable between the lifetime paths of consumption and labor. However, we allow for intertemporal nonseparabilities in preferences like habit formation. In this environment, we derive a generalized version of the Inverse Euler Equation and use it to show that intertemporal wedges characterizing optimal allocations of consumption can be strictly negative. We also show that preference nonseparabilities imply that optimal differentiable asset income taxes are necessarily retrospective in nature. We show that under weak conditions, it is possible to implement a socially optimal allocation using a social security system in which taxes on wealth are linear, and taxes/transfers are history-dependent only at retirement. The average asset income tax in this system is zero.     

Optimal Tax Policy, Market Imperfections, and Environmental Externalities in a Dynamic Optimizing Macro Model

This paper develops a dynamic real business cycle model that highlights pollution externalities (on welfare and production) and market imperfections and uses it to determine the socially optimal tax policy that encompasses labor income, capital income, and emission taxes. We show that the optimal tax on capital and labor income only addresses the production inefficiency (and is time-invariant), while the tax on the environmental externalities affects both the production inefficiency and the environmental spillovers (and is time-varying). More interestingly, the socially optimal emission tax will be characterized by a Keynesian-like stabilizer that is designed to mitigate business cycle fluctuations, i.e., that will stimulate the economy with a lower emission tax during recessions. In a positive analysis, we show that the beneficial effects arising from pollution taxation will become larger the greater is the degree of the firms' monopoly power. In addition, a triple dividend in terms of improving environmental quality and increasing employment and firms' profit can be simultaneously realized if the environmental production externality is more significant and if the elasticity of intertemporal substitution in consumption is relatively small.     

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.     

OPTIMAL CAPITAL TAXES FOR PUBLIC GOOD PROVISION*

This paper constructs a general equilibrium trade model of a small open economy that produces many traded private goods and one non-traded public consumption good. Trade in goods is free, but the country taxes the internationally mobile capital to finance the provision of the public good. Within this framework, the paper identifies the conditions under which the optimal policy on the internationally mobile capital calls for a tax. Under the assumptions that (i) the welfare function is concave with respect to the tax rate, and (ii) the net revenue-maximizing capital tax rate is positive, it is shown that the marginal cost of the public good always understates its social marginal cost.     

Tax Competition in Vertically Differentiated Markets with Environmentally Conscious Consumers

This paper analyses the effects of tax competition on environmental product quality, pollution and welfare in a two-country, vertically differentiated, international duopoly, in which consumers are environmentally conscious. The firm in each country chooses first the environmental quality of its product (which reflects the emissions generated in the production process) and then the price. In equilibrium one country will be more polluted than the other because firms choose different levels of environmental quality of their products. We find that a country’s optimal commodity tax is higher if the domestic firm is the more polluting supplier. Furthermore, non-cooperative commodity tax rates are inefficiently high in equilibrium. This is because, in this framework with environmentally aware consumers, commodity taxes affect the choice of firms regarding their emissions. Therefore, a domestic tax reduction not only raises the profits of the foreign firm but also lowers its emission levels, resulting in higher welfare for the other country. We also analyse the optimal cooperative and non-cooperative commodity and emission taxes with border tax adjustments. With these two policy instruments available, commodity taxes are higher.     

Direct versus indirect pigovian taxation

This paper considers the theory of optimal taxation in the presence of externalities when it is the uses of commodities in particular consumption processes which generate externalities, rather than the consumption of certain commodities as such. If the government is constrained to using ordinary commodity taxes (for reasons of imperfect information, costly control, etc.), it is demonstrated that there is a case for having taxes or subsidies on related goods in addition to a tax on the externality-creating commodity itself. The analysis also identifies the conditions under which related goods should be subsidized or taxed.     

Optimal Taxation in Life-Cycle Economies

We use a very standard life-cycle growth model, in which individuals have a labor-leisure choice in each period of their lives, to prove that an optimizing government will almost always find it optimal to tax or subsidize interest income. The intuition for our result is straightforward. In a life-cycle model the individual's optimal consumption-work plan is almost never constant and an optimizing government almost always taxes consumption goods and labor earnings at different rates over an individual's lifetime. One way to achieve this goal is to use capital and labor income taxes that vary with age. If tax rates cannot be conditioned on age, a nonzero tax on capital income is also optimal, as it can (imperfectly) mimic age-conditioned consumption and labor income tax rates. Journal of Economic Literature Classification Numbers: E62, H21.     

Effect of the Tax System ON R&D Intensity,Growth, Wages and Consumption Share

We propose a general equilibrium knowledge‐driven (semi‐)endogenous‐growth model with horizontal R&D, which is extended to consider two types of labour, skilled and unskilled, and exogenous government expenditure, financed through taxes on financial assets and on labour income, to analyse the implications of the tax system on R&D intensity, economic growth, wage inequality and consumption share in the output. In particular, we show that: (i) taxes have negative influence in the consumption share, being higher the marginal effect of the labour‐income tax; (ii) for any given government expenditure share, an increase (a decrease) in financial‐assets tax decreases (increases) the labour‐income tax; (iii) only the financial‐assets tax affects negatively the R&D intensity and the skill‐premium; thus, to reduce the skill‐premium the financial‐assets tax must increase; (iv) ignoring the effect on wage inequality and on R&D intensity, taxes are substitutes.     

Border tax adjustments and tariff‐tax reforms with consumption pollution

We develop a model of a small open economy, where pollution per unit of consumption between domestically produced and imported quantities of the same good differs. We show that the first‐best policy combination calls for consumption taxes on all polluting goods, and border tax adjustment (BTA) measures, that is, tariffs or import subsidies. We identify conditions under which well‐known tariff‐tax reform policies for developing economies, such as a consumer‐price‐neutral piecemeal reform of trade and a consumption tax, and a consumer‐price‐neutral reform of all trade and consumption taxes improve welfare. We also evaluate whether reforms of trade taxes alone are superior to consumer‐price‐neutral reforms of trade and consumption taxes.     

Optimal labor income taxation in a two-sector dynamic general equilibrium model

This paper presents a new approach to the two-sector optimal taxation problem. We derive the optimal labor income tax rate which depends on factor intensity across sectors. It is the labor intensity that determines the initial wage rate, and therefore the optimal labor tax rate. We show that an increase in the initial relative price of consumption goods decreases the optimal tax rate on labor income in the case that the consumption goods sector is capital-intensive while it increases the optimal tax rate on labor income in the case that the investment goods sector is capital-intensive.     

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).     

OPTIMAL TAXATION ON MIXED DIAMOND GOODS: IMPLICATIONS FOR PRIVATE CAR OWNERSHIP IN CHINA

Abstract. The ‘diamond effect’ exists when a consumer's utility depends on the exchange value, not just on the intrinsic consumption effects of the good. Yew‐Kwang Ng has discussed the optimal tax on a pure ‘diamond’ good. This paper extends Ng's model to cover mixed diamond goods. It uses three mathematical models to show that the optimal tax on a mixed diamond good with both intrinsic and diamond effects depends on the proportion of the diamond effect. The result may explain the violation of the Ramsey Rule in practice, and may be used to formulate private car taxes in China.     

Externality‐Correcting Taxes and Regulation*

In much of the literature on externalities, taxes and direct regulation have been considered as alternative policy instruments. Both instruments might be imperfect in practice, reflecting informational deficiencies and other limitations. We analyse the use of taxes and regulation in combination, to control externalities arising from individual consumption behaviour. We consider the cases either where taxes are imperfectly differentiated to reflect individual differences in externalities, or where some consumption escapes taxation. In both cases, we characterize the optimal instrument mix, and we show how changing the level of direct regulation alters the optimal externality tax.