Publications

2007
Martin A-B, Dirk T. G. R, Eytan S. Policies to Internalize Reciprocal International Spillovers. CESifo Working Paper Series [Internet]. 2007. Publisher's VersionAbstract

An effective policy scheme to overcome the suboptimal low provision levels of global public goods is developed in this paper. By suggesting a decentralized approach to raise environmental public good provision levels we take account of the lack of a coercive global authority that is able to enforce efficient international environmental regulations. In our model individual regions voluntarily commence international negotiations on public good provision, which are accompanied by side-payments. These side-payments are financed by means of regional externality-correcting taxes. Side-payments and national tax rates are designed in a mutually dependent way. The decentralized scheme we recommend for approaching Pareto efficient Nash equilibria is based on the ideas of Coasean negotiations and Pigouvian taxes. As it is implementable for a wide class of Nash solutions, it is applicable to various international externality problems.

Sheshinski E. Refundable Annuities (Annuity Options). [Internet]. 2007. Publisher's VersionAbstract

Individuals can insure themselves perfectly against uncertainty about the length of life by purchasing deferred annuities early in life. In the absence of other uninsurable uncertainties (e.g. income), there will be no residual purchases or sales of annuities later in life, thereby avoiding any adverse-selection. In contrast, the presence of such uncertainties creates an active residual annuity market based on the arrival of new information. We characterize the equilibrium in the residual annuity market and propose a new financial instrument, refundable annuities with a guaranteed refund price, which enables individuals who hold a portfolio of such annuities to better adjust [...]

Eytan S, Robert J. S. Introduction to Entrepreneurship, Innovation, and the Growth Mechanism of the Free-Enterprise Economies[Entrepreneurship, Innovation, and the Growth Mechanism of the Free-Enterprise Economies]. Introductory Chapters [Internet]. 2007. Publisher's VersionAbstract
How much credit can be given to entrepreneurship for the unprecedented innovation and growth of free-enterprise economies? In this book, some of the world's leading economists tackle this difficult and understudied question, and their responses shed new light on how free-market economies work–and what policies most encourage their growth. The contributors take as their starting point William J. Baumol's 2002 book The Free-Market Innovation Machine (Princeton), which argued that independent entrepreneurs are far more important to growth than economists have traditionally thought, and that an implicit partnership between such entrepreneurs and large corporations is critical to the success of market economies. The contributors include the editors and Robert M. Solow, Kenneth J. Arrow, Michael M. Weinstein, Douglass C. North, Barry R. Weingast, Ying Lowrey, Nathan Rosenberg, Melissa A. Schilling, Corey Phelps, Sylvia Nasar, Boyan Jovanovic, Peter L. Rousseau, Edward N. Wolff, Deepak Soma
Eytan S. Introduction to The Economic Theory of Annuities[The Economic Theory of Annuities]. Introductory Chapters [Internet]. 2007. Publisher's VersionAbstract
Annuities are financial products that guarantee the holder a fixed return so long as the holder remains alive, thereby providing insurance against lifetime uncertainty. The terms of these contracts depend on the information available to insurance firms. Unlike age and gender, information about individual survival probabilities cannot be readily ascertained. This asymmetric information causes market inefficiencies, such as adverse selection. Groundbreaking in its scope, The Economic Theory of Annuities offers readers a theoretical analysis of the functioning of private annuity markets. Starting with a general analysis of survival functions, stochastic dominance, and characterization of changes in longevity, Eytan Sheshinski derives the demand for annuities using a model of individuals who jointly choose their lifetime consumption and retirement age. The relation between life insurance and annuities that have a bequest option is examined and "annuity options" are proposed as a response
2006
Eytan S. Note on Longevity and Aggregate Savings. Scandinavian Journal of Economics [Internet]. 2006 :353. Publisher's VersionAbstract
In a recent paper in this journal, Bloom, Canning and Graham (2003) model the effect of changes in longevity on individual savings. They proceed to present empirical findings about the relation between longevity and "aggregate savings." There is a missing link between their empirics and theory: the changes in the populations age density distribution due to increased longevity. This note provides such an aggregation analysis within a simple model with uncertain survival, endogenous life-cycle consumption and retirement age. It is shown that, with continuous annuitization, an increase in expected longevity raises aggregate steady-state savings. The magnitude of this effect depends on the economy's age-specific distribution and on the elasticity of optimum retirement to changes in longevity. Copyright The editors of the "Scandinavian Journal of Economics" 2006 .
Sheshinski E. Optimum Commodity Taxation in Pooling Equilibria. [Internet]. 2006. Publisher's VersionAbstract
This paper extends the standard model of optimum commodity taxation (Ramsey (1927)and Diamond-Mirrlees (1971)) to a competitive economy in which markets are inefficient due to asymmetric information. Insurance markets are prime examples: consumers impose varying costs on suppliers but firms cannot associate costs with individual customers and consequently all are charged equal prices. In such a competitive pooling equilibrium, the price of each good is equal to the average of individual marginal costs weighted by equilibrium quantities. We derive modified Ramsey Boiteux Conditions for optimum taxes in such an economy and show that, in addition to the standard formula, they [...]
De Menil G, Murtin F, Sheshinski E. Planning for the optimal mix of paygo tax and funded savings. Journal of Pension Economics and Finance [Internet]. 2006 :1. Publisher's VersionAbstract
The paper uses an overlapping generations model to analyse the problem of a benevolent planner determining the pay-as-you-go tax rate and the level of funded savings, in an economy where both are policy variables. We characterize the conditions under which it is desirable to have both a positive tax rate and a positive level of savings. The optimal size of the tax rate and of savings depend both on the stochastic characteristics of earnings growth and the return to savings, and on the shape of the utility function of the representative agent. Among the comparative statics results presented, the central one is that increasing the variability of earnings raises the desirability of a pay-as-you-go system, under general conditions. This is consistent with earlier analyses of pay-as-you-go as a provider of intergenerational insurance. A numerical example using the CARA utility and normal distributions illustrates the calculation of optimal tax and savings levels, using annual data for post
Brito DL, Hamilton JH, Intriligator MD, Sheshinski E, Slutsky SM. Private information, Coasian bargaining, and the second welfare theorem. Journal of Public Economics [Internet]. 2006;90 :871 - 895. Publisher's VersionAbstract
Most of the debate about Coasian bargaining in the presence of externalities relates to the First Welfare Theorem: is the outcome under bargaining efficient? This debate has involved the definition and importance of transaction costs, the significance of private information, and the effect of entry. There has been little analysis of how Coasian bargaining relates to the Second Welfare Theorem: even if the bargaining outcome is efficient, does the process limit the set of Pareto optimal allocations which can be achieved? We consider a model in which individuals utilize a common resource and may affect each other's output. The individuals differ in their productivities or tastes and this information is private to each of them. The government can manage the common resource and use nonlinear taxes to correct for the externality or it can turn the common resource over to a private owner who can charge individuals to utilize it with a nonlinear fee schedule. The government and the owner hav
Eytan S. Optimum Commodity Taxation in Pooling Equilibri. Levine's Bibliography [Internet]. 2006. Publisher's VersionAbstract
This paper extends the standard model of optimum commodity taxation (Ramsey (1927) and Diamond-Mirrlees (1971)) to a competitive economy in which some markets are inefficient due to asymmetric information. As in most insurance markets, consumers impose varying costs on suppliers but …firms cannot associate costs to customers and consequently all are charged equal prices. In a competitive pooling equilibrium, the price of each good is equal to average marginal costs weighted by equilibrium quantities. We derive modi…ed Ramsey-Boiteux Conditions for optimum taxes in such an economy and show that they include general-equilibrium effects which re‡flect the initial deviations of producer prices from marginal costs, and the response of equilibrium prices to the taxes levied. It is shown that condition on the monotonicity of demand elasticities enables to sign the deviations from the standard formula. The general analysis is applied to the optimum taxation of annuities and life insurance.(Th
Sheshinski E. Differentiated annuities in a pooling equilibrium. [Internet]. 2006. Publisher's VersionAbstract
Regular annuities provide payment for the duration of an owner’s lifetime. Period-Certain annuities provide additional payment after death to a beneficiary provided the insured dies within a certain period after annuitization. It has been argued that the bequest option offered by the latter is dominated by life insurance which provides non-random bequests. This is correct if competitive annuity and life insurance markets have full information about individual longevities. In contrast, this paper shows that when individual longevities are private information, a competitive pooling equilibrium which offers annuities at common prices to all individuals may have positive amounts of both types [...]
Eytan S. Differentiated Annuities in a Pooling Equilibrium. CESifo Working Paper Series [Internet]. 2006. Publisher's VersionAbstract
Regular annuities provide payment for the duration of an owner’s lifetime. Period-Certain annuities provide additional payment after death to a beneficiary provided the insured dies within a certain period after annuitization. It has been argued that the bequest option offered by the latter is dominated by life insurance which provides non-random bequests. This is correct if competitive annuity and life insurance markets have full information about individual longevities. In contrast, this paper shows that when individual longevities are private information, a competitive pooling equilibrium which offers annuities at common prices to all individuals may have positive amounts of both types of annuities in addition to life insurance. In this equilibrium, individuals self-select the types of annuities that they purchase according to their longevity prospects. The break-even price of each type of annuity reflects the average longevity of its buyers. The broad conclusion that emerges from
Sheshinski E. Longevity and aggregate savings. [Internet]. 2006. Publisher's VersionAbstract
For the last fifty years, countries in Asia and elsewhere witnessed a surge in aggregate savings per capita. Many empirical studies attribute this trend to the highly significant increases in life longevity of the populations of these countries. Some argue that the rise in savings is shortrun, to be eventually dissipated by the dissaving of the elderly, whose proportion in the population rises along with longevity. This paper examines whether these conclusions are supported by economic theory. A model of life cycle decisions with uncertain survival is used to derive individuals’ consumption and chosen retirement age response to changes in [...]
Eytan S. Longevity and Aggregate Savings. CESifo Working Paper Series [Internet]. 2006. Publisher's VersionAbstract
For the last fifty years, countries in Asia and elsewhere have witnessed a surge in aggregate savings per capita. Some empirical studies attribute this trend to the increases in life longevity of the populations of these countries. It has been argued that the rise in savings is short-run, eventually to be dissipated by the dissaving of the elderly, whose proportion in the population rises along with longevity. This paper examines whether these conclusions are supported by economic theory. A model of life-cycle decisions with uncertain survival is used to derive individuals' consumption and chosen retirement age response to changes in longevity from which changes in individual savings are derived. Conditions on the age-profile of improvements in survival probabilities are shown to be necessary in order to predict the direction of this response. Population theory (e.g. Coale, 1952) is used to derive the steady-state population age density function, enabling the aggregation of individual
Eytan S. Optimum Commodity Taxation in Pooling Equilibria. CESifo Working Paper Series [Internet]. 2006. Publisher's VersionAbstract
This paper extends the standard model of optimum commodity taxation (Ramsey (1927) and Diamond-Mirrlees (1971)) to a competitive economy in which some markets are inefficient due to asymmetric information. As in most insurance markets, consumers impose varying costs on suppliers but firms cannot associate costs to customers and consequently all are charged equal prices. In a competitive pooling equilibrium, the price of each good is equal to average marginal costs weighted by equilibrium quantities. We derive modified Ramsey-Boiteux Conditions for optimum taxes in such an economy and show that they include general-equilibrium effects which reflect the initial deviations of producer prices from marginal costs, and the response of equilibrium prices to the taxes levied. It is shown that condition on the monotonicity of demand elasticities enables to sign the deviations from the standard formula. The general analysis is applied to the optimum taxation of annuities and life insurance.
Sheshinski E. Optimum commodity taxation in pooling equilibria. [Internet]. 2006. Publisher's VersionAbstract
This paper extends the standard model of optimum commodity taxation (Ramsey (1927) and Diamond-Mirrlees (1971)) to a competitive economy in which some markets are inefficient due to asymmetric information. As in most insurance markets, consumers impose varying costs on suppliers but firms cannot associate costs to customers and consequently all are charged equal prices. In a competitive pooling equilibrium, the price of each good is equal to average marginal costs weighted by equilibrium quantities. We derive modified Ramsey- Boiteux Conditions for optimum taxes in such an economy and show that they include general-equilibrium effects which reflect the initial deviations of [...]
Georges De M, Fabrice M, Eytan S. Planning for the optimal mix of paygo tax and funded savings. Post-Print [Internet]. 2006. Publisher's VersionAbstract
We analyze the optimal balance between social security taxation and private saving in the provision of retirement income in dynamically efficient economies, a question at the center of policy debates in Europe and the United States. We consider the relative importance for this question of the return to capital, the internal return of the pay-as-you-go system, and the variabilities and correlation (or independence) of labor earnings and the capital return. We analyse these influences theoretically in the context of a two-period, overlapping generations model with uncertainty. We use a new method to calibrate the model using annual data on GDP per worker and the total real return on equities, from 1950 to 2002, from which we infer the stochastic characteristics of lifetime labor income and the return to lifetime savings in the US, UK, France and Japan. We obtain a range of optimal, steady-state values of the social security tax and the rate of lifetime savings. When the relative rate of
Sheshinski E. Note on Longevity and Aggregate Savings. The Scandinavian Journal of Economics [Internet]. 2006 :353. Publisher's VersionAbstract
In a recent paper in this journal, Bloom, Canning and Graham (2003) model the effect of changes in longevity on individual savings. They proceed to present empirical findings about the relation between longevity and aggregate savings. There is a missing link between their empirics and theory: the changes in the populations age density distribution due to increased longevity. This note provides such an aggregation analysis within a simple model with uncertain survival, endogenous life-cycle consumption and retirement age. It is shown that, with continuous annuitization, an increase in expected longevity raises aggregate steady-state savings. The magnitude of this effect depends on the economy's age-specific distribution and on the elasticity of optimum retirement to changes in longevity.
Eytan S. Differentiated Annuities in a Pooling Equilibrium. Levine's Bibliography [Internet]. 2006. Publisher's VersionAbstract
Regular annuities provide payment for the duration of an owner's lifetime. Period-Certain annuities provide additional payment after death to a beneficiary provided the insured dies within a certain period after annuitization. It has been argued that the bequest option offered by the latter is dominated by life insurance which provides non-random bequests. This is correct if competitive annuity and life insurance markets have full information about individual longevities. In contrast, this paper shows that when individual longevities are private information, a competitive pooling equilibrium which offers annuities at common prices to all individuals may have positive amounts of both types of annuities in addition to life insurance. In this equilibrium, individuals self-select the types of annuities that they purchase according to their longevity prospects. The break-even price of each type of annuity reflects the average longevity of its buyers. The broad conclusion that emerges from
Eytan S. Optimum Commodity Taxation in Pooling Equilibri. Levine's Bibliography [Internet]. 2006. Publisher's VersionAbstract
This paper extends the standard model of optimum commodity taxation (Ramsey (1927) and Diamond-Mirrlees (1971)) to a competitive economy in which some markets are inefficient due to asymmetric information. As in most insurance markets, consumers impose varying costs on suppliers but firms cannot associate costs to customers and consequently all are charged equal prices. In a competitive pooling equilibrium, the price of each good is equal to average marginal costs weighted by equilibrium quantities. We derive modified Ramsey-Boiteux Conditions for optimum taxes in such an economy and show that they include general-equilibrium effects which reflect the initial deviations of producer prices from marginal costs, and the response of equilibrium prices to the taxes levied. It is shown that condition on the monotonicity of demand elasticities enables to sign the deviations from the standard formula. The general analysis is applied to the optimum taxation of annuities and life insurance.(Thi
2005
Dirk T.G. R, Eytan S. Transfers as a Means to Combat European Spillovers. Journal of Economics and Statistics (Jahrbuecher fuer Nationaloekonomie und Statistik) [Internet]. 2005 :699. Publisher's VersionAbstract
In 2004, there was a further enlargement of the European Union. Among the new member countries are eight Central and Eastern European countries. Especially the accession countries located directly at the border to the EU generate significant environmental spillovers harming the Union. These spillovers are mitigated but not deleted by the enlargement regulations. In this paper we will therefore analyze an instrument which many further diminish the spillover problems: transfers, which are conditional on a tightening of environmental policy in the accession countries. The environmental policy considered is the policy of environmental taxation.

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