Environment,public debt,and epidemics

We study whether fiscal policies, especially public debt, can help to curb the macroeconomic and health consequences of epidemics. Our approach is based on three main features: we introduce the dynamics of epidemics in an overlapping generations model to take into account that old people are more vulnerable; people are more easily infected when pollution is high; public spending in health care and public debt can be used to tackle the effects of epidemics. We show that fiscal policies can promote convergence to a stable disease-free steady state. When public policies are not able to permanently eradicate the epidemic, public debt, and income transfers could reduce the number of infected people and increase capital and GDP per capita. As a prerequisite, pollution intensity should not be too high. Finally, we define a household subsidy policy that eliminates income and welfare inequalities between healthy and infected individuals.     

A model of the optimal allocation of government expenditures

Government expenditures can be used for various socioeconomic objectives, including public education, consumption of public goods and services, and social protection. This paper analyzes the optimal allocation of public expenditures among these competing functions. We establish an overlapping generations model with heterogeneous individuals in which the government optimally chooses income tax, transfer payment, educational spending, and public consumption. Our model characterizes the transitional dynamics and the steady state of each function with and without a pay‐as‐you‐go intergenerational contract. We also conduct a simulation illustrating that the presence of an intergenerational contract may raise public consumption and social welfare in the steady state.     

Growth and welfare effects of stabilizing innovation cycles

We consider a simple model of innovation where equilibrium cycles may arise and show that, whenever actual capital accumulation falls below its balanced growth path, subsidizing innovators by taxing consumers has stabilizing effects, promotes sustained growth and increases welfare. Further, if the steady state is unstable under laissez faire, the introduction of the subsidy can make the steady state stable. Such a policy has beneficial effects as it fosters output growth along the transitional adjustment path, and increases the welfare of current and future generations.     

Effect of social security on fertility and savings: an overlapping generations model

Old-age pension schemes do not exist in most developing countries, so adults bear children as security investments for the future. This phenomenon leads to unduly high rates of population growth. It has been hypothesized that introducing social security programs in such countries would increase savings rates and reduce the number of children born over the long term. The author studies the general equilibrium effects of some social security programs on rates of population growth and capital accumulation within an overlapping generations framework with endogenous fertility and savings. Specifically, Raul's overlapping generations growth model is extended to study the general equilibrium effects of payroll-tax-financed and child-tax-financed social security programs. It is shown that if the rate of intergenerational income transfers from young to old or child care cost is low, competitive equilibrium leads toward overpopulation and capital accumulation in a modified Pareto optimal sense; a social security program in such a case is therefore Pareto improving. A fully-funded system is not neutral when financed by child taxes. Finally, it is also shown that unlike in the case of exogenous fertility where competitive equilibrium attains steady state only asymptotically, fertility, when endogenous, may attain a unique globally steady state in finite time.     

The Transfer Problem and Intergenerational Allocation in an Overlapping Generations Model

We investigate the transfer problem between two countries in the steady state in a one-sector overlapping generations model and explain how transfers should be shared between the young and old generations of the donor country and allocated across the generations of the recipient country. Except at the golden rule of capital accumulation, the ratios of the burden and distribution of transfers between the young and old generations affect welfare. We obtain the following results. First, the sharing of the transfer burden in the donor country depends on the relative size of two effects, namely, a negative direct effect and a positive indirect effect. If the former exceeds the latter, it is preferable for the donor country to allocate all of the transfer burden to the old generation and vice versa. Second, from the viewpoint of welfare maximization, it is preferable for the recipient country to distribute all of the transfers to the young generation. In contrast to the existing literature, these results suggest that the setting whereby the young generation of the donor country defrays all transfer costs may not be justifiable from the viewpoint of donor welfare maximization.     

THE POLITICAL ECONOMY OF ENVIRONMENTAL POLICY WITH OVERLAPPING GENERATIONS

A two‐sector overlapping generations model illuminates the intergenerational effects of a tax that protects an environmental stock. A traded asset capitalizes the economic returns to future tax‐induced environmental improvements, benefiting the current asset owners, the old generation. Absent a transfer, the tax harms the young generation by decreasing their real wage. Future generations benefit from the tax‐induced improvement in environmental stock. The principal intergenerational conflict arising from the tax is between generations alive at the time society imposes the policy, not between generations alive at different times. A Pareto‐improving tax can be implemented under various political economy settings.     

The taxation of capital returns in overlapping generations models

This paper shows that in the Diamond (1965) overlapping generations economy with production and capital savings, there is a period-by-period balanced fiscal policy supporting a steady state allocation that Pareto-improves upon the laissez-faire competitive equilibrium steady state (whether dynamically inefficient or efficient) without resorting to intergenerational transfers. The policy consists of taxing linearly (or subsidizing, in the dynamically efficient case) the returns to capital, while balancing the budget period by period through a lump-sum transfer (or tax, respectively) in second period. This intervention grants every generation the highest steady state utility attainable through markets (i.e. remunerating factors by their marginal productivities and without transfers) which under laissez-faire is not a competitive equilibrium outcome. A transition from the competitive equilibrium steady state to this other steady state is also Pareto-improving when the former is dynamically inefficient. The result disentangles from redistributive considerations the impact of the taxation of capital returns on steady state welfare, and thus provides a rationale for the taxation of capital returns that is based on efficiency considerations and not on redistributive goals.     

Capital income taxation in a growing world economy

This paper deals with dynamic adjustment in large economies to changes in the rate of capital income taxation or in the rate of investment tax credit in one country. The framework applied in the paper is a continuous-time, overlapping generations model with two countries. It features population growth and debt non-neutrality. We address impact and steady state effects of capital income tax and investment subsidy changes in the home country on consumption per capita, the capital intensity, and the per capita net foreign asset position in both countries. We also briefly consider individual welfare consequences of these policies.     

THE WELFARE GAINS OF AGE‐RELATED OPTIMAL INCOME TAXATION

Using an overlapping generations model with skill uncertainty and private savings, we quantify the gains of age‐dependent labor income taxation. The total steady‐state welfare gain of switching from age‐independent to age‐dependent nonlinear taxation varies between 2.4% and 4% of GDP. Part of the gain descends from relaxing incentive–compatibility constraints and part is due to capital‐accumulation effects. The welfare gain is of about the same magnitude as that which can be achieved by moving from linear to nonlinear income taxation. Finally, the welfare loss from tax‐exempting interest income is negligible under an optimal age‐dependent labor income tax.     

Implementing Steady State Efficiency in Overlapping Generations Economies with Environmental Externalities

We consider in this paper overlapping generations economies with pollution resulting from both consumption and production. The competitive equilibrium steady state is compared to the optimal steady state from the social planner's viewpoint. We show that the dynamical inefficiency of a competitive equilibrium steady state with capital–labor ratio exceeding the golden rule ratio still holds. Moreover, the range of dynamically efficient steady state capital ratios increases with the effectiveness of the environment maintenance technology, and decreases for more polluting production technologies. We characterize some tax and transfer policies that decentralize as a competitive equilibrium outcome the transition to the social planner's steady state.     

Envy and Inequality*

We present an overlapping generations economy, populated by heterogeneous agents who care about both consumption relative to others and the bequest they leave to their offspring. We show that saving and bequest rates vary across the income distribution, and we obtain several interesting results. First, envy reduces the steady‐state capital stock and increases the degree of inequality in consumption, capital ownership, and bequests. Second, if the bequest motive is sufficiently strong the equalizing effect of bequests disappears. Third, income inequality for a given cohort increases with age. Fourth, the distribution of inherited wealth becomes more unequal than that of wealth in general. Fifth, economic position becomes more persistent across generations.     

On Cost Benefit Rules for Green Taxes

This paper concerns the welfare effects of a green tax reform in a dynamic general equilibrium model with preexisting taxes on labor income and capital income. In comparison with previous studies on green taxes in dynamic models, which have focused their main attention on long run effects of such reforms, I derive cost benefit rules for a change in the tax mix by using the properties of the value function in optimal control theory. This enables me to relate the welfare effect of a change in the tax mix to responses in employment, the capital stock, (flow) emissions and the stock of pollution along the whole general equilibrium path. Another contribution of the paper is to examine under what conditions an emission tax, which is set permanently below the marginal damage of pollution, is welfare superior to an emission tax path that fully internalizes the external effect.     

On the dynamics of renewable resource harvesting and pollution control

The paper presents a dynamic partial equilibrium model which combines optimal renewable resource harvesting and optimal pollution control. Pollution accumulates as a slowly decaying stock and is assumed to affect the growth and the quality of the renewable resource stock. The aim is to maximize a social welfare functional which gives the present value of the difference between natural resource benefits and pollution control costs. The existence, uniqueness and the dynamic properties of the steady states are investigated. The analysis also gives a general result concerning the steady state of any two state variable optimal control problems.     

Precautionary Principle and Robustness for a Stock Pollutant with Multiplicative Risk

The interest shown by policy makers and economists in the precautionary principle indicates the importance of model uncertainty in global warming policy. I show that through robust control, policy makers can implement the precautionary principle to regulate a stock pollutant, and I analyze its effect on expected steady state pollution taxes, stocks and welfare. The paper is broadly comprised of a theoretical part and an application to global warming policy. I find that: (1) an increase in either uncertainty about the model or risk about abatement cost increases expected steady state pollution taxes; (2) a robust policy is preferred for any level of model uncertainty and this preference increases for either higher model uncertainty or higher multiplicative risk and (3) the effect on expected steady state pollution taxes and stock of introducing model uncertainty is relatively small for high levels of model uncertainty. These results advocate using robust policies for a stock pollutant in the presence of model uncertainty.      

Ramsey Equilibrium in a Two-Sector Model with Heterogeneous Households

We prove an existence theorem for a stationary perfect foresight equilibrium under borrowing constraints in a two-sector model with infinitely lived heterogeneous agents. The most patient agent holds all the capital in this solution. We also show that if the capital goods sector is capital intensive and capital income is increasing in the aggregate capital stock, then the aggregate capital stock eventually is monotonic and converges to the steady state stock. If the consumption goods sector is more capital intensive and capital income is increasing in aggregate capital we prove convergence to the steady state under more restrictive conditions. Periodic equilibria are shown to exist under weaker hypotheses. Journal of Economic Literature Classification Numbers: D52, D90, E13.     

Welfare improving distributionally neutral tax reforms

In a new model with incomplete markets, I quantitatively determine tax reforms that are welfare improving, distributionally neutral, and leave the budget balance unchanged in the long run. I consider a new reform. I eliminate capital income taxation and replace it with progressive consumption taxation, consisting of taxing necessities and luxuries at different rates. I compare steady states under various tax regimes. I find that progressive rather than uniform consumption taxation generates higher welfare gains in the long run and during the transition to the steady state. While this type of reform achieves redistribution neutrality only in the long run, it generates welfare gains for the whole population during the transition.     

Investments into education—Doing as the parents did

Empirical evidence suggests that parents with higher levels of education generally attach a higher importance to the education of their children. This implies an intergenerational chain transmitting the attitude towards the formation of human capital from one generation to the next. We incorporate this intergenerational chain into an OLG-model with endogenous human capital formation. In absence of any state intervention such an economy might be characterized by multiple steady states with low or high human capital levels. There are also steady states where the population is permanently divided into different groups with differing human capital and welfare levels. Compulsory schooling is needed to overcome steady states with low human capital and welfare levels. Tax financed education subsidies can lead to further pareto-improvements.     

Endogenous fertility,Ricardian equivalence,and debt management policy

This paper develops a model in which dynastic families optimally determine fertility. Government debt represents a tax on future generations and on childbearing; the Ricardian Equivalence Hypothesis does not hold. Debt is welfare reducing in that it distorts the fertility decision. An increase in government debt induces a decline in fertility and an increase in the steady state capital/labor ratio. If a government inherits an existing stock of debt, the 1st-best policy is to eliminate the debt immediately. In other situations the optimal debt management policy will not, in general, entail a total elimination of the debt.     

Occupational Choice and Dynamic Incentives

We study an overlapping generations version of the principal-agent problem, where incentive contracts are determined in general equilibrium. All individuals are workers when young, but have a choice between becoming entrepreneurs or remaining workers when old. Imperfections in the credit market give rise to rents in entrepreneurial activities involving capital. These rents motivate poor young agents to work hard and save to overcome the borrowing constraints. With a labour market that is subject to moral hazard, the increased effort raises social welfare. Policies that reduce credit market imperfections, or redistribute income, may reduce welfare by dampening this effect.     

Illiquid life annuities

In this paper, we consider illiquid life annuity contracts and show that they may be preferred to those illustrated by Yaari. In an overlapping generations economy, liquid life annuities are demanded only if the equilibrium is dynamically inefficient. However, an equilibrium displaying a positive demand for illiquid life annuities is indeed efficient. In this latter case, the welfare at steady state is larger if illiquid life annuity contracts are available.