on the desirability of taxing capital income in optimal social insurance abstract this paper analyzes optimal linear taxes on labor income and savings in a two period life cycle model with ex ante identical households endogenous leisure demands in both periods and general processes of skill shocks over the life cycle we demonstrate that the atkinson stiglitz theorem breaks down under risk capital taxes are employed besides labor income taxes for two distinct reasons i capital taxes reduce labor supply distortions on second period labor supply since second period labor supply and saving are substitutes ii capital taxes insure first period income risk although this benefit is partially off set because first period labor supply and saving are complements our results imply that retirement saving should not be actuarially fair

optimal social security with imperfect tagging workers are exposed to the risk of permanent disability we rely on a dynamic mechanism design approach to determine how imperfect information on health should optimally be used to improve the trade off between inducing the able to work and providing insurance against disability after deriving the fi rst order conditions to this problem we calibrate the model to the u s economy and run a numerical simulation the government should offer back loaded incentives and make strategic use of the difference between the age at which disability occurs and the age of eligibility to disability bene ts also the able who are mistakenly tagged as disabled should be encouraged to work until some early retirement age this makes a decrease in the strictness of the disability test desirable which would reduce the number of disabled who are not awarded the tag and hence improve insurance finally we show how the first best allocation of resources can asymptotically be implemented by making strategic use of the disability test

designing optimal disability insurance a case for asset testing we analyze an implementation of an optimal disability insurance system as a competitive equilibrium with taxes an optimum is implemented by an asset tested disability system in which a disability transfer is paid only if an agent has assets below a specified maximum the logic behind this result is that an agent who plans to falsely claim disability a finds doing so unattractive if he does not adjust his savings and b cannot collect disability insurance if he does adjust his savings in the desired direction upward for a calibrated economy we find that welfare gains from asset testing are significant

social security and retirement decision a positive and normative approach social insurance for the elderly is judged responsible for the widely observed trend towards early retirement in a world of laissez faire or in a first best setting there would be no such trend however when first best instruments are not available because health and productivity are not observable the optimal social insurance policy may imply a distortion on the retirement decision the main point we make is that while there is no doubt that retirement systems induce an excessive bias towards early in many countries a complete elimination of this bias i e a switch to an actuarially fair system is not the right answer this is so and for two reasons first some distortions are secondbest optimal this is the normative argument second and on the positive side the elimination of the bias might be problematic from a political perspective depending on the political process it may either not be feasible or alternatively it may tend to undermine the political support for the pension system itself

differential mortality and social security this paper studies the normative problem of redistribution between individuals who differ in their lifespans we discuss aspects related to the objective function and argue that aversion to multiperiod inequality should be taken into account then we study the properties of the social optimum both with full information and with asymmetric information we highlight the role of aversion to multiperiod inequality and show that it has substantial consequences on the design of social security schemes in particular we show that for a low resp high aversion to multiperiod inequality a negative resp positive implicit tax rate on continued activity is desirable

taxes and pensions pension benefit rules depend on individual history far more than taxes do and age plays a much larger role in pension determination than in tax determination apart from some simulation studies theoretical studies of optimal tax design typically contain neither a mandatory pension system nor the behavioral dimensions that lie behind justifications commonly offered for mandatory pensions conversely optimizing models of pension design typically do not include annual taxation of labor and capital incomes after spelling out this contrast and reviewing and rejecting zero taxation of capital income based on the atkinsonstiglitz and chamley judd results this article raises the issue of tax favored retirement savings a topic where the two subjects come together when i was a young economist i thought methodology was uninteresting and unnecessary just something old guys did when they didn t have anything better to do i taught theory and public finance and the applied theory i did was with an eye on relevance for policy questions although i had had almost no experience with thinking about policy just a summer job with the council of economic advisors under president kennedy now that i am at a stage where methodology is age appropriate i think it is important some of this comes from the natural aging process and some comes from my extended involvement in various policy processes primarily about pensions not taxes in particular i am concerned that too many economists take the findings of individual studies literally as a basis for policy thinking rather than seeking inferences from an individual study to be combined with inferences from other studies that consider other aspects of a policy question as well as with intuitions about aspects of policy that are not in the models to me taking a model literally is not taking the model seriously it is worth remembering that models are incomplete indeed that is what it means to be a model we construct multiple models to highlight different aspects of an issue so thinking thoroughly about policy calls for thinking through multiple models and requires recognizing issues that have not made it into any of the

increasing returns migrations and convergence abstract the paper investigates the link between convergence and factor mobility it contrasts the predictions of exogenous growth models where factor mobility is found to promote convergence with endogenous growth models where factor mobility invariably leads to a cumulative process of regional divergence the paper develops a simple model of regional growth with mobile factors increasing returns to scale and diminishing returns to the reproducible factor it also tries to provide more solid microfoundations to the specification of the migration choice because of diminishing returns to the reproducible factor the economy will not be able to generate endogenous self sustaining growth nevertheless the results suggest that even in the context of an exogenous growth model convergence is not warranted however convergence may occur for some particular constellations despite the presence of increasing returns to scale more precisely it is shown that convergence is more likely the greater is the scope for scale economies and somewhat paradoxically the lower is the degree of labor mobility

trade offs in means tested pension design abstract the means testing of age pension programs allows governments to control the receipt of pension benefits extensive margin and the benefit level intensive margin we investigate how the presence of the extensive margin influences the trade off between protecting the poorer elderly and the economic costs of distorting incentives to work and save of young individuals the means test effect via the extensive margin improves the insurance aspect but introduces opposing impacts on incentives that potentially have ambiguous welfare outcomes we characterize combinations of the maximum pension benefit and taper rate that balance the negative incentive effects and positive insurance effects

does schooling cause growth a number of economists find that growth and schooling are highly correlated across countries a model is examined in which the ability to build on the human capital of one s elders plays an important role in linking growth to schooling the model is calibrated to quantify the strength of the effect of schooling on growth by using evidence from the labor literature on mincerian returns to education the upshot is that the impact of schooling on growth explains less than one third of the empirical cross country relationship the ability of reverse causality to explain this empirical relationship is also investigated

social security retirement age and optimal income taxation it is often argued that implicit taxation on continued activity of elderly workers is responsible for the widely observed trend towards early retirement in a world of laissez faire or of first best efficiency there would be no such implicit taxation the point of this paper is that when first best redistributive instruments are not available because some variables are not observable the optimal policy does imply a distortion of the retirement decision consequently the inducement of early retirement may be part of the optimal tax transfer policy we consider a model in which individuals differ in their productivity and their capacity to work long and choose both their weekly labor supply and their age of retirement we characterize the optimal non linear tax transfer that maximizes a utilitarian welfare function when weekly earnings and the length of active life are observable while individuals productivity and health status are not observable c 2003 elsevier b v all rights reserved

a theory of wage dynamics a dynamic equilibrium model of long term implicit labour contracts under incomplete but symmetric information is developed workers are assumed to be risk averse and of unknown ability or productivity risk neutral firms learn as do workers about each worker s productivity by observing the worker s output over time it is shown that equilibrium contracts provide for wages which never decline with age and increase only when the worker s market value increases above his current wage in addition to characterizing the equilibrium wage contract we also derive some of its implications for the behaviour of aggregate wages across various groups of workers these implications explain some findings in the recent empirical literature on ageearnings profiles in particular our model can explain why earnings may be positively related to experience even after controlling for productivity as some empirical studies have indicated

economic growth and the structure of long term development this volume collects some of the papers presented at the 82nd round table conference of the international economic association that was organised in collaboration with fondazione eni enrico mattei the book considers different approaches to the analysis of economic growth and it is organised in five parts par i is devoted to empirical evidence part ii contains six papers which present a series of models based on different approaches but with special emphasis on endogenous growth and on schumpeterian models of growth and fluctuations part iii of the book is devoted to the impact of international trade on economic development part iv examines the effects of economic development on the natural environment the final part of the book part v contains the concluding evaluations contributors p aghion r aversi d ben david g bertola o castellino f donati g dosi w easterly s fabiani c freeman r goodwin j helliwell e helpman p howitt r king m landesmann r levine s lombardini k g maler w d nordhaus l l pasinetti s rebelo a sen l soete r m solow m syrquin b verspagen s zervos

a reconsideration of import substitution this paper studies the origins of an import substitution strategy of development summarizes the consequences of that strategy and reviews the problems that led to its failure the fundamental difficulty was its discouragement of the indigenous social learning necessary for sustained independent development the emergence of an outward oriented minimal government strategy is due to the success of korea and taiwan this strategy fails to recognize that social learning requires a strong role for national agents and that this role can be penalized by undue openness an effective strategy must protect and induce domestic learning without penalizing exporting

critical survey endogenous growth theory a critical assessment a critical assessment is made of endogenous growth theory from the perspective of recent developments within economics as a discipline these include its increasing mathematical formalisation its focus upon microfoundations the casual use of econometrics to test models and the incorporation of factors that have traditionally been outside mainstream economics it is found that the theory focuses upon market imperfections and technological progress in a variety of ways and reconstructs their impact upon the macroeconomy as a growth rather than as a level effect whilst the growth rate is endogenised this leads to the problem of multiple equilibria and extremely complex dynamics the generalisation from exogenous growth theory is however associated with even more extreme assumptions and analytical distance from the socioeconomic processes of growth itself copyright 2000 by oxford university press

optimal taxation of risky human capital in a two period life cycle model with ex ante homogeneous households earnings risk and a general earnings function we derive the optimal linear labor tax rate and optimal linear education subsidies the optimal income tax trades off social insurance against incentives to work education subsidies are not used for social insurance but they are only targeted at offsetting the distortions of the labor tax and internalizing a fiscal externality both optimal education subsidies and tax rates increase if labor and education are more complementary because education subsidies indirectly lower labor tax distortions by stimulating labor supply optimal education subsidies taxes also correct non tax distortions arising from missing insurance markets education subsidies internalize a positive negative fiscal externality if there is underinvestment overinvestment in education because of risk education policy unambiguously allows for more social insurance if education is a risky activity however if education hedges against labor market risk optimal tax rates could be lower than in the case without education subsidies

market simulation and the provision of public goods a non paternalistic response to anomalies in environmental evaluation most normative economics assumes that individuals have coherent preferences this paper responds to growing evidence of failures of this assumption particularly in the context of stated preference methods widely used in environmental policy analysis it proposes a non paternalistic concept of consumer sovereignty that does not assume preference coherence is satisfied by competitive markets and can be applied to the provision of public goods a key implication is that decisions should reflect valuations revealed at the point of consumption such valuations which can be inferred from hedonic prices may be less susceptible to willingness to accept wta willingness to pay wtp disparities than those elicited by stated preference methods

the transformation of competitive advantage in east asia an analysis of technological and trade specialisation summary in recent years there has been considerable interest in the relationship between a country s export competitiveness and the role played by technology in strengthening and maintaining competitive advantage a central feature of recent empirical work mainly focused on the oecd countries has rested on examining patterns of export and technological specialization between economies and sectors this paper moves attention away from the advanced industrialized economies to examine the trends for trade and technological specialization among the east asian developing economies in particular two aspects of specialization are examined first to what extent have patterns of competitive advantage changed over time and second to measure the relationship between patterns of trade and technological specialization important differences are found in the patterns of specialization and in the relationship between them among the advanced east asian economies and those catching up

payroll tax financed social insurance with variable retirement the optimal relationship between retirement benefits and retirement age is derived the model assumes ex ante identical workers zero one labor supply no private savings wages and payroll taxes constant over life random onset of an inability to work and the impossibility of distinguishing those unable to work from those choosing retirement this formulation is meant to capture some issues for retirement programs where governments commonly do not measure disability e g ages 65 70 with intertemporally additive preferences optimal benefits rise with the age of retirement but more slowly than would be actuarially fair a nonadditive example is also considered

optimal indirect and capital taxation we consider an environment in which agents skills are private information and follow arbitrary stochastic processes we prove that it is typically pareto optimal for an individual s marginal benefit of investing in capital to exceed his marginal cost of doing so this wedge is consistent with a positive tax on capital income we also prove that it is pareto optimal for the marginal rate of substitution between any two consumption goods to equal the marginal rate of transformation this lack of a wedge is consistent with uniform taxation of consumption goods within a period

economic aspects of optimal disability benefits this paper analyzes optimal disability and retirement or welfare benefits with imperfect disability evaluation with some able workers judged disabled and some disabled workers judged able thus the levels of both disability and retirement benefits affect labor supply with anyone not working eligible for retirement benefits we analyze the optimal structure of benefits for a given disability screening mechanism and briefly consider the problem of optimal evaluations of disability evidence in the united states there is an overlap in eligibility for disability and retirement portions of social security more generally welfare is sometimes available to people denied disability benefits

the case for a progressive tax from basic research to policy recommendations the fair distribution of the tax burden has long been a central issue in policyhe fair distribution of the tax burden has long been a central issue in policymaking a large academic literature has developed models of optimal tax making a large academic literature has developed models of optimal tax theory to cast light on the problem of optimal tax progressivity in this theory to cast light on the problem of optimal tax progressivity in this paper we explore the path from basic research results in optimal tax theory to paper we explore the path from basic research results in optimal tax theory to formulating policy recommendations formulating policy recommendations models in optimal tax theory typically posit that the tax system should maximize a models in optimal tax theory typically posit that the tax system should maximize a social welfare function subject to a government budget constraint taking into account social welfare function subject to a government budget constraint taking into account that individuals respond to taxes and transfers social welfare is larger when resources that individuals respond to taxes and transfers social welfare is larger when resources are more equally distributed but redistributive taxes and transfers can negatively are more equally distributed but redistributive taxes and transfers can negatively affect incentives to work save and earn income in the fi rst place this creates the clasaffect incentives to work save and earn income in the fi rst place this creates the classical trade off between equity and effi ciency which is at the core of the optimal income sical trade off between equity and effi ciency which is at the core of the optimal income tax problem in general optimal tax analyses maximize social welfare as a function of tax problem in general optimal tax analyses maximize social welfare as a function of individual utilities the sum of utilities in the utilitarian case the marginal weight for individual utilities the sum of utilities in the utilitarian case the marginal weight for a given person in the social welfare function measures the value of an additional dollar a given person in the social welfare function measures the value of an additional dollar of consumption expressed in terms of public funds such welfare weights depend on of consumption expressed in terms of public funds such welfare weights depend on the level of redistribution and are decreasing with income whenever society values the level of redistribution and are decreasing with income whenever society values more equality of income therefore optimal income tax theory is fi rst a normative more equality of income therefore optimal income tax theory is fi rst a normative theory that shows how a social welfare objective combines with constraints arising from theory that shows how a social welfare objective combines with constraints arising from limits on resources and behavioral responses to taxation in order to derive specifi c limits on resources and behavioral responses to taxation in order to derive specifi c

a model under siege a case study of the german retirement insurance system this study evaluates the positive and negative features of the german public pension system and discusses three reasons for its increasing perceived and real difficulties maturation negative incentive effects and the problems of demographic change the german system in its current form may be able to limp through the coming decades but will cease to be the exemplary bismarckian machine that has created generous retirement incomes at reasonable tax rates current policy proposals are insufficient and a few but incisive design changes and some degree of prefunding could rescue the many positive aspects of the german retirement insurance system