Demand and distance: Evidence on cross-border shopping

An important issue for commodity taxation is the extent to which changes in foreign taxes affect the extent of cross-border shopping and thereby, domestic tax revenue. We use data from Swedish municipalities to estimate how responsive alcohol sales are to foreign prices, and relate the sensitivity to the location’s distance to the border. Typical results suggest that the elasticity with respect to the foreign price is around 0.3 in the border region; moving 150 (400) km inland reduces the cross-price elasticity to 0.2 (0.1). Our estimates suggest that a recent Danish cut in the spirits tax reduced Swedish tax revenues from spirits sales by more than 2%, and that an attempt by Sweden to cut taxes in response would reduce tax revenues further.     

Estimating the elasticities of gasoline demand: an instrumental variable approach

This article uses a new identification strategy to estimate the demand for gasoline. I show that the monthly gasoline price is endogenous to gasoline demand at the state level, and that gasoline tax and domestic oil first purchasing price together are strong and valid instruments to correct for the endogeneity bias. In addition to estimating the price elasticity, this article also provides an estimate of the income elasticity. These updated estimates are critical factors in evaluating the environmental effect of gasoline tax and forecasting gasoline consumption.     

SOME EMPIRICAL EVIDENCE ON DEMAND SYSTEM* AND OPTIMAL COMMODITY TAXATION

We have two major tasks in this paper. The first is to obtain a reasonable estimate of the Japanese demand system, which includes leisure, income and commodity choices. The second is to compute and evaluate the optimal tax equilibrium. The estimation result, based on the Almost Ideal Demand System, is found to be consistent with the microeconomic theory. We evaluate the optimal commodity tax structure by calculating the equilibria under lump‐sum, optimal commodity and uniform commodity taxation schemes. The deadweight losses under uniform taxation are very small, and the optimal commodity tax rates are strikingly close to uniform.     

Optimal taxation with consumption time as a leisure or labor substitute

This paper studies the optimal commodity taxation problem when time taken in consumption is a perfect substitute for either labor or leisure. It shows that while labor substitutability affects the optimal tax structure, leisure substitutability leaves the classical optimal tax results intact. In the Ramsey tax framework with linear income taxes, whether the consumers have the same or different earning abilities, labor substitutes tend to be taxed at a higher rate than leisure substitutes with the tax differential being increasing in consumption time. This is not necessarily the case when one allows for nonlinear income taxation.     

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.     

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.     

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 Tax Policy under Environmental Quality Competition

This paper studies the socially optimal emission and commodity tax policy when consumers are willing to pay a price-premium for environmentally friendlier variants of a commodity vertically differentiated in environmental quality. The first-best levels of quality can be obtained by a combination of a uniform ad valorem tax and an emission tax (or a subsidy for buying green products). The first-best emission tax is higher than the social valuation of the positive externality associated with average environmental quality. Regardless of environmentally conscious consumers, if only one instrument is available, the second-best emission tax is equal to the social valuation of the positive externality associated with average environmental quality. A uniform ad valorem tax increases welfare only if the social valuation of the positive externality associated with average environmental quality is low enough.     

The Welfare Effects of Environmental Taxation

Recent literature has investigated whether the welfare gains from environmental taxation are larger or smaller in a second-best setting than in a first-best setting. This question has mainly been addressed indirectly, by asking whether the second-best optimal environmental tax is higher or lower than the first-best Pigouvian rate. Even this indirect question has itself been approached indirectly, comparing the second-best optimal environmental tax to a proxy for its first-best value, marginal social damage (MSD). On closer examination, however, MSD becomes ambiguously defined and variable in a second-best setting making it an unreliable proxy for the Pigouvian rate. Given these observations, the current analysis reevaluates these welfare questions and finds that when compared directly to its first-best value, the second-best optimal environmental tax generally rises with increased revenue requirements. Even in cases where the second-best environmental tax is lower than its first-best value, the welfare gains may be greater than in a first-best setting. These results suggest that the marginal fiscal benefit (revenue recycling effect) exceeds the marginal fiscal cost (tax base effect) over a range of environmental tax rates that, for benchmark models, extends above the first-best Pigouvian rate. These findings reinforce the intuition that environmental policy complements rather than competes with the provision of other public goods.     

Optimal taxation of externalities interacting through markets: A theoretical general equilibrium analysis

This study develops a theoretical general equilibrium model to examine optimal externality tax policy in the presence of externalities linked to one another through markets rather than technical production relationships. Analytical results reveal that the second-best externality tax rate may be greater or less than the first-best rate, depending largely on the elasticity of substitution between the two externality-generating products. These results are explored empirically for the case of greenhouse gas and nitrogen emissions associated with biofuels and petroleum.     

Poverty alleviation and tax policy

This paper examines public good provision and tax policy—optimal non-linear income taxation and linear commodity taxation—when the government departs from purely welfarist objective function and seeks to minimise poverty. This assumption reflects much policy discussion and may help understand some divergences of practical tax policy from lessons in optimal tax analysis. In contrast to Atkinson and Stiglitz (J. Public Econom. 6 (1976) 55), it may be optimal to use differentiated commodity tax rates, including the taxation of savings, even if preferences are separable in goods and leisure. The optimal effective marginal tax rate at the bottom of the distribution may be negative, suggesting that wage subsidy schemes can be optimal. Finally, optimal provision of a public good is analysed under poverty minimisation.     

Hourly wage rate and taxable labor income responsiveness to changes in marginal tax rates

Recently, a voluminous literature estimating the taxable income elasticity has emerged as an important field in empirical public economics. However, to a large extent it is still unknown how the hourly wage rate, an important component of taxable income, reacts to changes in marginal tax rates. In this study we use a rich panel data set and a sequence of tax reforms that took place in Sweden during the 1980s to estimate the elasticity of the hourly wage rate as well as the taxable labor income elasticity with respect to the net-of-tax rate. We also estimate elasticities with respect to the non-labor income in a way that is novel in the literature. While carefully accounting for the endogeneity of marginal tax rates we find a statistically significant response in wage rates both among married men and women. The estimates of the hourly wage rate elasticity with respect to the net-of-tax rate fall in the range of 0.14–0.16 for males and 0.41–0.57 for females, whereas the corresponding taxable labor income elasticity estimates hover between 0.19–0.21 for males and 0.96–1.44 for women. Moreover, for men we find that the taxable labor income elasticity with respect to non-labor income is statistically significant; the point estimate being ? 0.07. This implies that the compensated taxable labor income elasticity is about 5 percentage points higher than the uncompensated one. In general, we consider the estimates for males to be more certain and robust than the estimates for females.     

Optimal income taxation when couples have endogenous bargaining power

This study examines the optimal income taxation for a two-earner household, where the couple bargains over their private goods consumption and time allocation between work and leisure. In the model, bargaining power is determined endogenously by the income gap between the two earners. Conventional studies have shown that the higher income tax rate should be imposed on the individual with the smaller wage elasticity, typically the individual with the higher productivity. In contrast to conventional argument, this study shows that the optimal tax rate on the household member with the higher productivity is lower than that of the individual with the lower productivity if the required tax revenue is relatively small and the influence of the gender income gap on the power balance of the couple is moderate. This is because such a tax structure encourages the labor supply of the individual with the higher productivity to mitigate the decrease in the household’s consumption induced by income taxation.     

Optimal Commodity Taxes in Australia

The recent changes to commodity taxes in Australia have led to renewed interest in a classic question in public finance: should the tax rates be uniform or differentiated? This article attempts to answer this question by calculating optimal commodity taxes in Australia for a nine‐item disaggregation. The estimates point to non‐uniform commodity taxes, even from the viewpoint of an inequality‐insensitive tax planner. The optimal commodity taxes bear little resemblance with the pre‐GST or post‐GST tax rates. No less significant is our observation that even the purely efficiency‐driven optimal commodity taxes imply lower real expenditure inequality than the actual taxes.     

On the Optimality of Restricting Credit: Inflation Avoidance and Productivity

The paper presents a model in which the consumer uses up resources in order to avoid the inflation tax through the use of exchange credit. In an example economy without capital, the credit tax is optimal when the resource loss from credit use dominates the productivity effect and the inefficiency of substitution towards leisure as a result of the credit tax. The paper also examines second-best inflation policy in this context, given a credit tax. It then extends the economy to an endogenous growth setting and shows how restricting inflation avoidance can increase productivity.
JEL Classification Numbers: E13, E51, E61, G21.     

An instrumental variables approach to estimating tax revenue elasticities: Evidence from Sub-Saharan Africa

This paper exploits the significant response of real GDP growth of Sub-Saharan African countries to exogenous international commodity price and rainfall shocks to construct instrumental variables estimates of the tax revenue elasticity IV estimates yield that a 1% increase in GDP increases tax revenues by up to 2.5%.     

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.     

The Optimal Asymptotic Income Tax Rate

This paper shows that a policy maker needs only two types of information to set the optimal income tax rate at the top: a measure of labor supply elasticity and the shape of skills distribution. We find that the asymptotic tax rate is not affected by the degree of inequality aversion as long as the marginal utility of consumption converges to zero. By using empirically plausible estimates for the compensated labor supply elasticity and the shape of skills distribution, we find that the optimal marginal tax rate at the top should be between 33% and 60%, which is in line with the existing rates in the real world.     

Optimal size of the government: the role of the elasticity of substitution

This paper analyzes the optimal fiscal policy in an endogenous growth model with productive public services. Government expenditure, which may be subject to different degrees of congestion, is financed by distortionary income taxation. The standard result on the equality between the growth-maximizing, welfare-maximizing and first-best income tax rates holds if and only if production is Cobb–Douglas or there is proportional congestion. With non-proportional (or in the absence of) congestion, the first-best income tax is lower than the (second-best) welfare-maximizing income tax which, in turn, is lower than the growth-maximizing income tax if the elasticity of substitution is below unity. Under mild conditions these relations are reversed if the elasticity of substitution is above unity. Intuition on these results is also provided.     

Some Marginalist Intuition Concerning the Optimal Commodity Tax Problem

The author offers a simple intuition that can be exploited to derive and to help interpret some canonical results in the theory of optimal commodity taxation. He develops and explores the principle that the marginal social welfare loss per last unit of tax revenue generated be equalized across tax instruments. A simple two-consumer, two-taxed-commodity economy is used to explore how this intuition can be used to derive the famous inverse elasticity rule, as well as the modifications and extensions needed to account for the redistributive effects of commodity taxes.