Externalities in a spatial context: The case of air pollution

In this paper air pollution externalities are analyzed in an explicit spatial setting that recognizes the spatial interdependence of polluters and their victims. Optimal environmental policies are shown to consist not only of Pigouvian taxes but of two other policies. First, regulations controlling the allocation of land between polluters and victims are needed. Secondly, if pollution taxes are imposed by local governments, in general it will be necessary for the federal government to take some of the tax proceeds and redistribute them amongst localities. For example, some of the proceeds in heavily taxed and polluted communities may have to be redistributed to lightly taxed and polluted communities.     

Optimal tax rules and public sector efficiency with an externality in an overlapping generations model

This paper examines optimal tax rules and public sector efficiency, integrating them in a second-best world with pollution by using an overlapping generations model. The second-best world is characterized by the comparative statics of green preferences. The main results obtained are as follows. First, the marginal cost of public funds may be reduced by the externalities, regardless of the choice of taxes. Second, optimal environmental and non-environmental tax rules are additively and directly affected by the dynamic efficiency of capital accumulation per unit labour (DECAL), and indirectly by it, through the efficiency of the public sector. Environmental taxes going beyond Pigovian ones may be welfare-improving if the DECAL is improved by the environmental tax. Even optimal non-environmental tax rules should additively and directly counter the dynamics of pollution to consider the income effects of the optimal tax system for the future. Third, the “additivity property,” or the “principle of targeting,” does not hold even in the absence of incentive compatibility constraints. The essential reasons for this are clarified as follows: distortions that should be countered by taxes; that is, the income effects of the optimal tax system and the DECAL in this model, break the equality between optimal environmental taxes and the externalities measured by governments. Finally, growing environmental concerns may, in fact, increase pollution. The inverse relationship between environmental and labour income taxes may not hold.     

Environmental taxation,information precision,and information sharing

We analyze how environmental taxes should be optimally levied in a sequential game in which regulators and firms face costs uncertainties. First, the regulator chooses the intensity of emissions taxes to reduce externalities. Then, facing common and private information with noisy signals, firms compete in the marketplace and choose outputs. We show that, under nonuniform quality of signals across firms, the regulator may calibrate differentiated tax policy. We also show that the social impact of more precise private signals hinges largely and fundamentally on the value of the ratio of the slopes of the marginal damage and the marginal consumer surplus. Finally, we investigate information sharing between polluters and its impacts on welfare. We stress that, when there are threats of severe environmental damages under deep uncertainties, collusion is welfare reducing and may jeopardize the regulatory process. Regulators need to set an appropriate precautionary policy. Numerical simulations illustrate the results that the model delivers.     

WELFARE‐MAXIMISING PRICING IN A MACROECONOMIC MODEL WITH IMPERFECT COMPETITION AND CONSUMPTION EXTERNALITIES

This paper develops a simple macroeconomic model with imperfect competition and consumption externalities, and uses it to examine whether the marginal cost pricing rule in the partial equilibrium framework can apply to the general equilibrium framework. It is shown that, for welfare to be maximised, average revenue should be set equal to marginal cost if consumption externalities are either absent or positive. However, for welfare to be maximised, average revenue should be set higher than marginal cost in the presence of negative consumption externalities.     

Incentive generating state dependent penalty system: The case of income tax evasion

Penalty systems can very often be looked upon as corrective measures established in order to eliminate or reduce costly externalities generated by optimizing economic agents. Hence, penalties can be viewed as regulatory measures and their efficient structure should be of interest to economists. We propose a dynamic incentive generating penalty system which, if instituted, may reduce, at a given cost, the generation of undesirable externalities. The special case to which we refer is income tax evasion, although our scheme should be applicable to any kind of externalities, such as pollution of the environment, violation of antirust laws and others which are created by repititive actions of economic agents.     

Regulating chemical emissions with risk-based environmental taxation

This paper develops a policy of risk-based environmental taxation for chemical emissions. A scoring index of chemical risk values for target pollutants first takes into account potential human health risk and ecological risk. A common tax base called the risk unit, which reflects the risk values from the scoring index, is then identified for individual pollutants. By determining the number of risk units for target emissions and levying a single tax rate on one risk unit, the risk-based tax system assigns a different pollution price to each chemical release. The policy sets rates according to marginal damage and provides target industry with permanent incentive for pollution abatement. By narrowing the gap between the marginal private cost and constrained marginal social cost of the chemical emission externality, the environmental tax system creates efficiency gains.     

Optimal taxation and cross-price effects on labor supply: Estimates of the optimal gas tax

This study estimates parameters necessary to calculate the optimal second-best gasoline tax, most notably the cross-price elasticity between gasoline and leisure. Prior theoretical work indicates the importance of this elasticity, but despite this, almost none of the prior studies of commodity taxation (and none of the studies on second-best environmental regulation) actually estimate it. Using household data, we find that gasoline is a relative complement to leisure, and thus that the optimal gasoline tax is significantly higher than marginal damages-the opposite of the result suggested by the bulk of the prior literature. Indeed, even if there were no externalities at all associated with gasoline, the optimal tax rate would still be almost equal to the average gas tax rate in the U.S. Following this approach to estimate cross-price elasticities with leisure could strongly influence estimates of optimal rates for other important commodity or pollution taxes.     

A Montero payment mechanism for regulating non-point pollution emissions

Regulating externalities from pollution is difficult when the regulator can not observe individual firms’ externality generation. Taxing the aggregate emissions of a group of polluters, which can often be observed, has been suggested. However, these taxes are vulnerable to collusion and strategic behavior, and they generate distorted entry-exit incentives. To address these disadvantages, I suggest combining an aggregate tax mechanism with the quota payment mechanism suggested by Montero for allocating emission quotas. The suggested tax system induces compliance with quotas and solves the noted problems for a subset of these regulation problems.     

Optimal pollution taxation in a Cournot duopoly

It is well known that the optimal pollution tax in a competitive industry is equal to the marginal damage inflicted by the pollution. It has also been shown that the optimal pollution tax on a monopoly is less than the marginal damage. In this paper, I derive the optimal pollution tax for a Cournot duopoly. If firms have different production costs, the optimal tax rate may exceed the marginal damage. This is so because the tax may be an effective instrument for allocating production from the less to the more efficient firm. It is also shown that, if one firm has a positive most preferred pollution tax, the sum of consumer and producer surpluses will be declining in the tax at this level.     

Who should bear the administrative costs of an emissions tax?

All environmental policies involve costs of implementation and management that are distinct from pollution sources’ abatement costs. In practice, regulators and sources usually share these administrative costs. We examine theoretically an optimal policy consisting of an emissions tax and the distribution of administrative costs between the government and regulated sources of pollution. Our focus is on the optimal distribution of administrative costs between polluters and the government and the optimal level of the emissions tax in relation to marginal pollution damage. We demonstrate how the policy variables affect aggregate equilibrium administrative costs and show that these effects are generally indeterminate, as is the effect of the distribution of administrative costs on aggregate emissions. Consequently, the optimal sharing of administrative costs and whether the optimal emissions tax is higher or lower than marginal damage depend on specific contexts.     

Prices versus Quantities in a Second-Best Setting

The choice between taxes and tradable permits has been independently analysed by two distinct research traditions. The first proceeds from Weitzman's partial equilibrium stochastic model and concludes that a tax should be preferred if the marginal abatement cost curve is steeper than the marginal environmental benefit curve. The second utilises deterministic general equilibrium models with pre-existing distortionary taxes. It concludes that non-revenue-raising instruments (e.g., grandfathered tradable permits) are costlier than revenue-raising ones (e.g., a tax on every unit of pollution or auctioned permits). To build a bridge between these two traditions, we introduce in Weitzman's model a positive cost of public funds due to pre-existing distortionary taxes. The tax admits a greater comparative advantage over the permits, as compared to Weitzman's classical result. Then, we assume that the regulated industry blocks any proposal that poses it too high an expected burden. This may require a transfer to firms, in the form of freely-allocated permits or lump-sum tax rebate. It turns out that if this acceptability constraint is binding, then the comparative advantage of taxes over permits is still reinforced. Quantitatively, even if the marginal benefit function is 50% more steeply sloped than the marginal cost function, the price instrument should be preferred. We also compare the expected net benefit of these two instruments to a contingent instrument which leads to the ex post optimum. The superiority of the contingent instrument over the quantity one is higher than in first-best.     

Consumption externality, efficiency and optimal taxation in one-sector growth model

In an economy with consumption externalities, existing studies find that a competitive equilibrium is efficient in the long run and remains efficient in transitions if preferences are homothetic. This paper revisits the efficiency issue in an otherwise standard one-sector growth model where consumption externalities affect a utility via their effects on the time preference. We find that even if preferences are homothetic, the externality changes the marginal rate of substitution between now and future and leads to a disparity in the intertemporal elasticity of substitution between the centrally planned economy and a decentralized economy. As a result, a competitive equilibrium is inefficient in transition dynamics. We characterize an optimal tax/subsidy structure that enables the allocation in a decentralized economy to replicate the social optimum.     

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.     

IMPROVING ENVIRONMENTAL POLICY: ARE MARKETS THE SOLUTION?

While market approaches are clearly valuable for improving U.S. environmental policy, they cannot solve all of the problems, and not necessarily the most difficult ones. They can ensure that a given total abatement is achieved at minimum cost. But, if pollution damages depend on how abatement effort is allocated among polluters, this is not necessarily the most desirable outcome. One also needs to be sure that the potential gains from trade implicit in market solutions will actually be realized within some given time; the empirical evidence here is not necessarily promising. Rather than how aggregate abatement should be distributed among polluters, the chief difficulty often lies in determining how much overall abatement is required. A key factor that economists tend to overlook is the difficulty of ascertaining just how benefits vary with abatement effort. Uncertainty and risk aversion in connection with the marginal benefit curve may explain regulatory actions that are otherwise hard to justify.     

Optimal Management of Environmental Externalities with Time Lags and Uncertainty

Many environmental externalities occur with time lags that can range from a few days to several centuries in length, and many of these externalities are also subject to uncertainty. In this paper, we examine the key features of an optimal policy to manage environmental externalities that are both lagged and stochastic. We develop a two-period, two-polluter model and obtain closed-form solutions for optimal emissions levels under different combinations of damage functions and stochastic processes. These solutions show that it is not obvious whether greater control should be exerted on polluters that generate externalities with longer lags or on polluters that generate externalities with shorter lags. We find that the optimal ranking of polluters with respect to the length of the time lag associated with their externality will depend on (a) the discount rate, (b) conditional expectations of future states of the polluted resource, (c) persistence of the pollutant, and (d) initial conditions.     

我国生活废弃物的经济分析与对策

I. Introduction Domestic wastes refer to discharges that are produced by our daily life or other social activities and cannot be utilized or recycled within certain time and spatial extent. Firstly, the sources of domestic wastes are various and scattered, such as wastes produced by consumption, various rubbishes in daily life etc. Domestic wastes in- volve every field, enterprise, and individual. However, the wastes have not been treated rationally to lead to envi- ronmental pollution. Secon…     

When redistribution makes personalized pricing of externalities useless

We consider a standard optimal taxation framework in which consumers' preferences are separable in consumption and labor and identical over consumption, but are affected by consumption externalities. For every nonlinear, income-dependent pricing of goods there is a linear pricing scheme, combined with an adjusted income tax schedule, that leaves all consumers equally well-off and weakly increases the government's budget. The result depends on whether a linear pricing scheme exists that keeps the aggregate amount of consumption at its initial level observed under nonlinear pricing. We provide sufficient conditions for the assumption to hold. If adjusting the income tax rate is not available, personalized prices for an externality can enhance social welfare if they are redistributive, that is, favor consumers with a larger marginal social value of income.     

气候政策的时间不一致性问题研究

经验证据表明,很多国家都很难严格执行既定的气候政策。从理论上证明追求社会福利最大化的政府在经济剩余、政府税收收入和碳排放的负外部性等多重目标约束条件下,实施碳税政策时会产生时间不一致现象。结果表明,即使考虑到公共资金的边际成本,由于企业投资的不可逆转性和沉淀性,相对社会最优而言政府也会在事后降低碳税率,导致更多的能源消费和更多的碳排放。为克服时间不一致问题带来的效率损失,建议政府应建立独立的碳排放管制机构,对碳税政策做出可置信的承诺,改变电源结构,鼓励减排技术的投资,完善碳交易市场。     

工业水污染税税率测算模型的构建与应用

］本文探索建立水污染税税率测算模型并应用设计水污染税率。首先,在比较国内外水污染税费制度的基础上,借鉴环境税和环境保护相关理论,将水污染经济损失模型与内梅罗修正指数模型相结合构建水污染税测算模型;第二,采用水污染税测算模型测算了2010年河北省水污染税税率水平应为14元/吨废水。这一标准远高于现行对每吨废水平均征收030元的标准,验证了我国水污染征收标准远不足以弥补治污成本的现状,应在环境税费改税改革中重新设计征税依据和税率水平。     

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).