市场结构、环境税与福利效应分析

运用短期局部均衡分析方法研究完全竞争市场和垄断市场条件下环境税对社会福利的影响.结果显示:在完全竞争市场条件下,对企业征收环境税可以增进社会福利.而在垄断市场条件下,环境税的福利效应具有不确定性,这取决于垄断造成的扭曲程度.如果垄断造成的扭曲较小,环境税仍然可以提高社会福利.但无论是增进抑或降低社会福利,对垄断企业征收环境税都不可能实现最优化,因为环境税在矫正污染外部性的同时,垄断造成产量水平下降导致福利损失增加,所以只能追求一个次优的结果,次优环境税低于完全竞争条件下的标准环境税.     

Prices versus quantities: environmental regulation and imperfect competition

By exercising market power, a firm will distort the production, and therefore the emissions decisions, of all firms in the market. This paper examines how the welfare implications of strategic behavior depend on how pollution is regulated. Under an emissions tax, aggregate emissions do not affect the marginal cost of polluting. In contrast, the price of tradable permits is endogenous. I show when this feedback effect increases strategic firms’ output. Relative to a tax, tradable permits may improve welfare in a market with imperfect competition. As an application, I model strategic and competitive behavior of wholesalers in a Mid-Atlantic electricity market. Simulations suggest that exercising market power decreased emissions locally, thereby substantially reducing the regional tradable permit price. Furthermore, I find that had regulators opted to use a tax instead of permits, the deadweight loss from imperfect competition would have been even greater.     

Green Tax Reform and Competitiveness

This paper studies a revenue-neutral green tax reform that substitutes energy for wage taxes in an open economy with unemployment. As long as the labour tax rate exceeds the energy tax rate, such a reform will increase employment, reduce the domestic firms' unit cost of production and hence increase international competitiveness and output of the economy. The driving force behind these results is the technological substitution process that a green tax reform will bring about. The resulting reduction in unemployment is welfare increasing since energy, which the country has to buy at its true national opportunity cost, is replaced with labour, whose price is above its social opportunity cost.     

Oil Price Instability and Domestic Energy Substitution for Imported Oil*

This paper considers the effects of unstable world oil prices on domestic firms seeking substitutes for imported oil. Price instability manifested as price uncertainty is shown to inhibit domestic potential competitors' substitution activities, being analogous to a tax imposed on domestic firms by the dominant oil-exporters. This tax analogue of price uncertainty is in distinction to the mutual gain scenario of stochastic limit pricing when there is price variability but no uncertainty.     

Ambiguous Social Welfare Effects of Price Regulation Under Imperfect Competition

Conventional wisdom is that a binding price ceiling increases output and so increases social welfare if imposed on an imperfectly competitive market. However, this paper shows that a price ceiling can be harmful to social welfare even though it increases industry output and consumer surplus. This model can be applied to the pharmaceutical industry under price control in many countries, e.g., U.K., Canada, Germany and Japan.     

Macroeconomic effects of an indirect tax substitution

We study an indirect tax reform in a general equilibrium model with imperfect competition for both the Cournot and the Free entry equilibria. We show that it is possible to attain a positive balanced budget multiplier by means of a substitution of specific by ad valorem taxation. Moreover, although any tax substitution causes higher prices and the flow up of firms in the long-run, the Free entry equilibrium output can increase with respect to that of the Cournot equilibrium. Finally, in contrast with the partial equilibrium, welfare decreasing tax reforms are likely to occur even when the balanced budget multiplier is positive.      

SUBSIDIES AS OPTIMAL FISCAL STIMULI

Theoretical macroeconomic models typically take fiscal policy to mean tax‐and‐spend by a ‘benevolent government’ that exploits potential aggregate demand externalities inherent in the imperfectly competitive nature of goods markets. Whilst shown to raise aggregate output and employment, these policies crowd‐out private consumption and typically reduce welfare. On account of their widespread use to stimulate economic activity, we consider the use of ‘tax‐and‐subsidize’ instead of ‘tax‐and‐spend’ policies. Within a static general equilibrium macro‐model with imperfectly competitive goods markets, we examine the effects of wage and output subsidies and show that, for a small open economy, positive tax and subsidy rates exist which maximize welfare, rendering no intervention suboptimal. We also show that, within a two‐country setting, a Nash non‐cooperative symmetric equilibrium with positive tax and subsidy rates exists, and that cooperation between governments in setting these rates is more expansionary and leads to an improvement upon the non‐cooperative solution.     

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.     

An integrated tax-subsidy policy for carbon emission reduction

A carbon tax is often cited by economists as an effective instrument to mitigate greenhouse gas emissions, but there is little political interest in the United States. In light of this political unpopularity, we develop and examine a net-revenue constrained carbon tax and subsidy program. The optimal revenue constrained tax and subsidy schedule based on our utility maximization model taxes energy sources with high emissions to energy price ratio, and subsidizes sources with low emissions to energy price ratios. This approach may be more palatable than a traditional carbon tax because it can change the relative price of low and high emissions energy sources while providing a mechanism to limit net tax increases and energy price increases. We find that a constrained tax/subsidy program provides welfare gains relative to a no-tax scenario. Welfare gains are estimated to be 1% and 36% of the welfare gains from a Pigouvian tax for the motor fuels industry and electric power industry, respectively. In contrast, subsidies for low-emitting energy sources funded from general tax funds rather than from high-emission energy tax revenues lead to welfare decreases substantially below our proposed tax/subsidy policy approach.     

Efficiency properties of binary ecolabeling

We investigate efficiency properties of binary ecolabels in a homogeneous good market with heterogeneous consumers. Faced with the minimum technology standard, firms make endogenous entry, certification, and price/quantity decisions. We consider both perfect and imperfect competition with or without sunk fixed costs. Our findings are as follows. Ecolabeling alone does not achieve the first-best outcome and, to achieve the second best, may need to set the standard less strict than the efficient level. Without sunk fixed costs, ecolabeling can achieve the first-best outcome provided that both the technology standard and the complementary pollution tax are set at efficient levels. With sunk fixed costs, however, differential excise taxes that would restore allocative efficiency induce more entry than optimal, and thus, can be even welfare decreasing relative to no tax outcome. Tightening the technology standard may ameliorate such an adverse effect of the corrective tax system by reducing excessive entry and pollution per output by the certified firms.     

Carbon Taxation, Fuel Substitution and Welfare in Australia

This paper examines the potential role for fuel substitution in electricity production in reducing carbon dioxide emissions over a ten-year time horizon. This is achieved by adding fuel substitution to output changes resulting from demand responses arising from a tax on carbon dioxide emissions. A time profile of adjustments is developed. The tax required for Australia to meet a 20 per cent reduction in emissions from 1993 levels is calculated and effects on inequality and social welfare are examined. The paper also examines the potential effect of a subsidy towards the use of low-emission fuels, financed from the carbon tax. A subsidy produces an improvement in emissions abatement and a lower tax required to reach the emissions target.     

价格歧视战略与福利效应分析

在完全竞争市场条件下 ,竞争均衡可实现帕累托最优效率。垄断市场一般很难提供价格等于边际成本的产量水平 ,其产量与价格选择对社会来说不是最优的。垄断厂商以内生范畴和外生范畴为基础对消费者进行分类 ,使得价格歧视成为一种可行战略。由于定价策略存在差异 ,不同类型的价格歧视便具有不同的福利效应。     

Forward Markets and the Behaviour of the Competitive Firm with Production Flexibility

This paper examines the production and hedging decisions of the competitive firm under output price uncertainty when a forward market for its output is available. The firm possesses production flexibility in that it makes its production decision after the resolution of the output price uncertainty, albeit subject to a capacity constraint on production. We show that the firm optimally acquires a higher level of capacity investment than an otherwise identical firm with no production flexibility. We further show that production flexibility allows the firm to implicitly hedge against its output price risk exposure by the ex post production decision. The firm as such under‐hedges its output price risk exposure in the forward market wherein the forward price contains a non‐positive risk premium.     

A welfare anomaly in the rate-of-return regulated monopoly model which creates opportunities for offsetting taxation and regulatory policies

The impact of the property tax on a fair rate of return regulated firm is examined. We find that a change in the tax rate has exactly the same effect on factor employment, output and hence the price as an equivalent change in the allowed rate of return. However, an increase in the allowed rate of return will lead to higher profits, whereas the same increase in the property tax rate will decrease profits. We find that an increase in the tax rate or allowed rate of return may result in a net increase in social welfare. This result contradicts the long-established belief that a lower (or no) tax is preferred to a higher tax rate in maximizing welfare. Finally, a linear iso-welfare locus is derived which creates the possibility of the regulatory agency or the tax authority offsetting the negative effects of the other's policy.     

Pollution Abatement Investment When Environmental Regulation Is Uncertain

In a dynamic model of a risk-neutral competitive firm that can lower its pollution emissions per unit of output by building up abatement capital stock, we examine the effect of a higher pollution tax rate on abatement investment both under full certainty and when the timing or the size of the tax increase is uncertain. We show that a higher pollution tax encourages abatement investment if it does not exceed a certain threshold rate. However, akin to the Diamond-Mirrlees tax anomaly, it is possible that a higher pollution tax rate results in more pollution. The magnitude uncertainty discourages abatement investment, but at the time of the actual tax increase the abatement investment path may shift either upward or downward. On the other hand, when the timing is uncertain, the abatement investment path always jumps upward, thus suggesting that the effect of magnitude uncertainty on the optimal investment path may be more pronounced than that of timing uncertainty. Further, we show that the ad hoc practice of raising the discount rate to account for the uncertainty leads to underinvestment in abatement capital. We show how the size of this underinvestment bias varies with the future tax increase. Finally, we show that a credible threat to accelerate the tax increase can induce more abatement investment.     

Increasing Returns, Learning, and Beneficial Tax Competition

We analyze the welfare impact of entrepreneur mobility in a two‐country overlapping generations model. Increasing returns in production yield multiple equilibria that are stable under adaptive learning. Governments compete for the mobile resource by setting income taxes. We show that large welfare gains can arise from noncooperative taxation. If expectational barriers prevent the realization of high output equilibria, tax competition can sufficiently perturb expectations so that high steady states become attainable. Once in a high production regime, governments may institute cooperative tax increases or reductions so as to bring the economy to the global joint optimum without disturbing the regime.     

Bidding in an Electricity Pay-as-Bid Auction

One of the main elements of the recent reform of electricity trading in the United Kingdom is the change from a uniform price auction in the wholesale market to discriminatory pricing. We analyze this change under two polar market structures (perfectly competitive and monopolistic supply), with demand uncertainty. We find that under perfect competition there is a trade-off between efficiency and consumer surplus between the two auction rules. We also establish that a move from uniform to discriminatory pricing under monopoly conditions has a negative impact on profits and output (weakly), a positive impact on consumer surplus, and ambiguous implications for welfare and average prices.     

A decomposition of the Harberger expression for tax incidence

In this paper we propose a decomposition of the Harberger expression for the incidence of the corporate income tax into ‘commodity price distortion’ and ‘factor price distortion’ effects. By applying Harberger's estimates of the parameters for the U.S. economy, we will demonstrate that the factor price distortion effect, which has an extremely simple formal expression, explains 115 percent of the total effect of the tax change on the rate of return. This suggests that the commodity price distortion effect may be relatively unimportant in explaining the tax incidence. The difference between our two effects and Mieszkowski's (1967) output and factor substitution effects is also noted.     

The cost effect in third-degree price discrimination

In the presence of a non-constant marginal cost and demand uncertainty, we show that an output increase is no longer a necessary condition for welfare to increase following the introduction of third-degree price discrimination. We thus highlight the existence of an effect that might offset the well known output and misallocation effects of price discrimination. We propose a specific example where this is indeed the case.     

Regret theory and the competitive firm

This paper examines the production decision of the competitive firm under uncertainty when the firm is not only risk averse but also regret averse. Regret-averse preferences are characterized by a modified utility function that includes disutility from having chosen ex-post suboptimal alternatives. The extent of regret depends on the difference between the actual profit and the maximum profit attained by making the optimal production decision had the firm observed the true realization of the random output price. If the firm is not too regret averse, we show that the conventional result that the optimal output level under uncertainty is less than that under certainty holds. Using a simple binary model wherein the random output price can take on either a low value or a high value with positive probability, we show the possibility that the firm may optimally produce more, not less, under uncertainty than under certainty, particularly when the firm is sufficiently regret averse and the low output price is very likely to prevail.