uncertainty and optimal taxation in defense of commodity taxes abstract this paper re examines the theory of optimal commodity taxation in the presence of a linear income tax under wage uncertainty there are two categories of goods the consumption levels in one group are committed to before the resolution of uncertainty and those of the other after the paper i characterizes the structure of the optimal commodity taxes in view of the insurance they provide against random wage movements ii proves that optimal taxation requires a mix of differential commodity taxes and a uniform lump sum tax and iii demonstrates that the post uncertainty goods should face a positive tax rate which is higher than the tax rate on the pre committed goods

job mobility and earnings instability there is still no consensus on the causes of the increase in the variance of transitory earnings earnings instability in the united states it is difficult to attribute the rise in instability to job mobility because there is no evidence of a concurrent increase in job turnover or separations using an error component model of the covariance structure of earnings on panel survey of income dynamics and survey of income and program participation data this study shows that job mobility and the increase in the variance of wage changes upon job change accounts for a substantial part of the increase in earnings instability the empirical evidence is consistent with the simulations of a search and matching model where an increase in the variance of productivity shocks increases on the job search and earnings instability among job changers while leaving job turnover approximately constant jel j21 j31

capital taxation and accumulation in a life cycle growth model almost all of the serious economic work on savings decisions within the past decade has relied on some variant of the life cycle hypothesis in which savings arise out of individual choices of an optimum lifetime consumption path this paper reexamines the incidence and welfare consequences of capital income taxes within a realistic life cycle model the results suggest that the elimination of capital income taxation would have very substantial economic effects for example a complete shift to consumption taxation might raise steady state output by as much as 18 percent and consumption by 16 percent the long run welfare gain from such a shift would for plausible parameter values exceed 150 billion annually stated somewhat differently shifting to consumption taxation would raise the lifetime utility of the representative consumer by the equivalent of about six years income in the new steady state these estimates dwarf estimates of the static welfare cost of taxation and significantly exceed even extreme previous estimates of the dynamic loss this study departs from earlier analyses of the effects of taxes on capital income in several respects probably the most important difference between this treatment and most preceding ones lies in the assumptions about the interest elasticity of saving it is shown below that the common two period formulation of saving decisions yields quite misleading results a more realistic model of life cycle savings demonstrates that for a wide variety of plausible parameter values savings are very interest elastic this implies that shifting away from capital income taxation would significantly increase capital formation making possible long run increases in consumption many studies of the welfare effects of capital income taxation have ignored the general equilibrium effects of increased capital formation in an economy with life cycle savings there is no presumption that the undistorted growth path corresponds to any sort of social optimum as peter diamond has shown life cycle savings can lead to a steady state capital intensity either greater or less than the golden rule level more generally it is clear that there is no reason to believe that a life cycle economy will maximize any particular intertemporal social welfare function a fundamental tenet of welfare evaluation is that preexisting distortions must be considered in evaluating the consequences of tax changes the results presented in this paper take explicit account of the nonoptimal character of the no tax steady state this explains in large part why such a sizeable welfare effect of capital taxes is found in an economy far from the golden rule level of capital intensity there are substantial gains in steady state consumption achievable through increased capital formation section i of the paper examines the aggregate savings function in a continuous time life cycle framework the second section clarifies the differences between wage and consumption taxes an aggregate production function is added to complete the model in the third section the effects of changes in capital taxes on both steady state incidence and welfare are considered within a general equilibrium framework the final section of the paper discusses some implications of the results and suggests areas which appear to warrant further study assistant professor of economics massachusetts institute of technology and research analyst national bureau of economic research i am grateful to alan auerbach martin feldstein laurence kotlikoff to the participants in the nber workshop on business taxation and to the harvard public finance seminar for useful discussions james poterba and james buchal performed the numerical calculations

optimal policy and the risk properties of human capital reconsidered abstract this paper considers how optimal education and tax policy depends on the risk properties of human capital a key feature of human capital investments is whether they increase or decrease wage risk in a benchmark model it is shown that this feature alone determines whether a constrained optimal allocation should be characterized by a positive or a negative education premium in the same model a positive intertemporal wedge is optimal the robustness of these results is explored in two generalizations nonobservability of education and nonobservability of consumption finally policies that implement the constrained efficient allocations are considered

earnings instability and earnings inequality of males in the united states 1967 1991 although much research has focused on recent increases in annual earnings inequality in the united states the increases could have come from either of two sources the distribution of lifetime earnings could have become more unequal or the receipt of lifetime earnings could have become more unstable based on an analysis of the 1968 92 panel study of income dynamics we find that lifetime earnings inequality increased during the early 1980s and that earnings instability increased during the 1970s we also examine how these trends are related to changes in the distribution of wages and hours and the returns to education

optimal wage taxation when human capital and employment are endogenous this paper studies how optimal wage tax conclusions from the classic two period life cycle model of human capital accumulation are affected by endogenizing the number of taxpaying workers in the absence of a corrective policy young individuals underinvest in human capital from a social perspective because tax premiums for transfers to nonworkers are not actuarially adjusted downward for human capital attainment a combination of wage taxes and wage subsidies can restore proper price signals numerical simulations suggest that even modest employment elasticities can be sufficient to substantially impact the magnitudes and even the signs of optimal wage tax rates jel h21 h3 j24

trends in the transitory variance of male earnings methods and evidence we estimate the trend in the transitory variance of male earnings in the united states using the michigan panel study of income dynamics from 1970 to 2004 using an error components model and simpler but only approximate methods we find that the transitory variance started to increase in the early 1970s continued to increase through the mid 1980s and then remained at this new higher level through the 1990s and beyond thus the increase mostly occurred about 30 years ago its increase accounts for between 31 and 49 percent of the total rise in cross sectional variance depending on the time period

why are u s women decreasing their labor force participation if their wages are rising given the traditional interpretation of women s labor force participation rate lfpr trends as movements along a positively sloped labor supply curve it is surprising that the recent downward trend in u s women s lfpr has occurred over a period when women s real wages were commonly believed to be rising i find that almost two thirds of the decline since 2000 is attributable to aging of the adult female population the remainder due to declining labor force participation for women under 55 becomes less puzzling in light of my evidence that the wage education locus faced by women actually may have worsened since 2000 jel j21 j31 j82

earnings inequality and mobility in the united states evidence from social security data since 1937 this paper uses social security administration longitudinal earnings micro data since 1937 to analyze the evolution of inequality and mobility in the united states annual earnings inequality is u shaped decreasing sharply up to 1953 and increasing steadily afterward short term earnings mobility measures are stable over the full period except for a temporary surge during world war ii virtually all of the increase in the variance in annual log earnings since 1970 is due to increase in the variance of permanent earnings as opposed to transitory earnings mobility at the top of the earnings distribution is stable and has not mitigated the dramatic increase in annual earnings concentration since the 1970s long term mobility among all workers has increased since the 1950s but has slightly declined among men the decrease in the gender earnings gap and the resulting substantial increase in upward mobility over a lifetime for women are the driving force behind the increase in long term mobility among all workers

human capital accumulation and the optimal level of unemployment insurance provision previous studies of optimal unemployment insurance ui design ignore the impact of ui on human capital investment decisions we show that fully experience rated ui increases investment in human capital when future employment opportunities are not known with certainty in the presence of wage taxation the optimal level of ui trades off full insurance and the impact through human capital of ui on the wage tax base this trade off in turn depends on the extent to which human capital accumulation reallocates labor between market and untaxed nonmarket activities taxation of ui benefits increases the optimal level of ui provision

growth rate heterogeneity and the covariance structure of life cycle earnings using u s panel data on adult males i compare the profile heterogeneity model of earnings dynamics in which the earnings experience profile varies across individuals to a competing model in which earnings has a unit root the latter specification enjoys increasing popularity among researchers my analysis questions this favor suggesting the profile heterogeneity model provides a more consistent representation of the data i also provide new estimates of the variation in earnings growth rates previous evidence is from relatively unrepresentative samples individuals one standard deviation above the mean enjoy a 20 30 earnings advantage in just 10 years

investments in human capital wage uncertainty and public policy abstract the importance of risk characteristics of human capital for the design of tax and education policy is explored wages are uncertain and education while increasing the expected wage may increase or decrease wage variance the government has strong reasons to encourage human capital formation in the latter case partly due to the insurance effect of human capital and partly due to the way the individuals under a plausible restriction on prudence respond to changes in risk the analysis is illustrated using two models of education one where education helps the individuals make better occupational choices and a standard risk augmented becker type model

the rise of the states u s fiscal decentralization in the postwar period article i nfo article history one of the most dramatic changes in the fiscal federalism landscape during the postwar period has been the rapid growth in state budgets which almost tripled as a share of gdp and doubled as a share of government spending between 1952 and 2006 we argue that the greater role of states cannot be easily explained by changes in tiebout forces of fiscal competition such as mobility and voting patterns and are not accounted for by demographic or income trends rather we demonstrate that much of the growth in state budgets has been driven by changes in intergovernmental interactions restricted federal grants to states have increased and federal policy and legal constraints have also mandated or heavily incentivized state own source spending particularly in the areas of education health and public welfare these outside pressures moderate the forces of fiscal competition and must be taken into account when assessing the implications of observed revenue and spending patterns

changes in earnings instability and job loss this paper examines the contribution of job loss or displacement to increasing male earnings instability between 1970 and 1991 earnings instability increased among both displaced and not displaced men so changes associated with job loss cannot fully explain rising instability changes in the incidence and consequences of job loss did however add substantially to growing earnings instability and to the overall variance of earnings there is evidence that displacement substantially raised earnings volatility for several years after job loss that effect combined with increased numbers of recently displaced workers in the 1980s relative to the previous decade contributed to rising overall earnings instability

decomposing trends in income volatility the wild ride at the top and bottom we use 2 year panels from the current population survey to provide a detailed accounting of family income volatility from 1980 to 2009 volatility doubled overall and the increase was most pronounced among the top 1 of the income distribution but in any given year the level of volatility among the bottom 10 exceeds that of the top the increased volatility comes from higher instability of head and spouse earnings other nonlabor income and from reduced covariance between these income sources with the tax system this suggests that current tax policy is less effective in mitigating income shocks than previous decades jel j31 i30

intergenerational transmission of risk attitudes a revealed preference approach using data the german socio economic panel gsoep we investigate whether the willingness to take risks which is revealed via observed choices of occupation is transmitted from parents to children our approach resembles the one by dohmen et al 2008 who investigate the same question using stated preferences as risk variable we use earnings risk measured by the cross sectional coecient of residual variation obtained from mincerian wage regressions we nd that fathers riskiness of the job chosen is a signicant determinant of sons occupational risk our results are robust to dierent specications underpinning the hypothesis of intergenerational transmission of risk preferences

trends in the transitory variance of earnings in the united states we decompose the rise in cross sectional variance of male annual earnings in the united states from 1969 to 1996 into permanent and transitory components we find that the variance of permanent earnings began rising in the the late 1970s and has continued to rise in the 1980s the variance of transitory earnings also rose in the 1980s but declined in the 1990s there are lags in the earnings process which require a structural model to pinpoint the exact calendar times at which the changes in trends occurred

taxation of mobile factors as insurance under uncertainty this paper considers the effects of the taxation of mobile factors i e capital under uncertainty the wages earned by residents of a jurisdiction are uncertain due to random shocks since the uncertain wages in a jurisdiction depend on the amount of mobile capital employed in the jurisdiction and since taxation alters the quantity of capital employed taxation affects the riskiness of uncertain wages in particular the taxation of capital moderates the fluctuation of uncertain wages thereby providing insurance for this reason jurisdictions use distortionary capital taxation even if lump sum taxation is available in addition this insurance effect counteracts the tendency toward too low tax rates on capital arising from tax competition and possibly improves the efficiency of tax competition

did household consumption become more volatile i show that after accounting for predictable variation arising from movements in real interest rates preferences and income shocks liquidity constraints and measurement errors volatility of household consumption in the us increased by 25 percent between 1970 and 2004 the increase was lower than that of volatility of family income nonwhite and those with less than 13 years of education for whom there was no differential increase in income volatility experienced a significantly larger increase in volatility of household consumption substantial differences in wealth and access to credit markets point to the main reason for this divide jel d12 d14 e21 j15

causes of increased competition in the u s economy 1939 1980 examines the sources of increased competition in the united states u s between 1939 to 1980 in this paper authors consider the review of related literature trends and patterns of competitive structure in the u s economy influence of antirust actions on competition

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

earnings instability and tenure we study the effect of tenure on earnings instability in italy using two alternative estimation strategies first we use a descriptive measure of earnings instability and fixed effects regressions second we develop a formal model of earnings dynamics distinguishing permanent from transitory earnings and exploit variation of tenure and instability over time and across birth cohorts in estimation we use the two approaches also to evaluate earnings instability associated with temporary contracts short tenure contracts our results indicate that each year of tenure on the job reduces earnings instability on average by 11 workers on a temporary contract have an earnings instability up to 50 higher than workers on a permanent contract

unemployment insurance wage dynamics and inequality over the life cycle we investigate the relationship between life cycle wages and individual membership of unemployment insurance schemes in denmark we separate permanent from transitory wages and characterise them using membership of unemployment insurance funds we find that unemployment insurance is associated with lower wage growth heterogeneity over the life cycle and greater wage instability changing the nature of wage inequality from permanent to transitory although we are in general unable to formally test for moral hazard against adverse selection into unemployment insurance robustness checks suggest that moral hazard is the relevant interpretation

regulatory reform and technical change new evidence of scale economics in trucking economists have long argued against the regulation of motor carriers in the united states because the industry has been considered to be competitive in nature federal control of trucking has produced inefficiently high rates as well as costs advocates of regulatory reform have foreseen benefits accruing to shippers and consumers in general as greater rate freedom the entry of new firms and the removal of regulatory constraints lead motor carriers to reduce costs 16 and lower prices 17 many of these projected benefits were premised on the perceived competitive market structure of the trucking industry these perceptions have been largely supported by pre deregulation cost studies of general freight carriers which have found evidence of either constant returns to scale or diseconomies of scale friedlaender and wang chiang 8 find that for 20 interregional carriers over 1965 73 the typical firm operating at the sample mean is subject to mild scale diseconomies in a subsequent study of multiproduct economies of scale using 1976 proprietary data they 14 obtain the same basic results the typical firm has constant returns to scale while the representative large firm operates under moderate diminishing returns daughety nelson and vigdor 4 also find mild decreasing returns to scale for a panel of firms spanning 1953 58 in another study over 1974 79 friedlaender and bruce 6 find slight economies of scale for the typical firm based on simulations with the largest and smallest firms in their sample they suggest that over time large carriers have become more characterized by scale economies and small carriers by scale diseconomies however their evidence is far from clear cut given this conventional wisdom that the technology of the less than truckload segment of this industry was constant returns to scale before deregulation few if any economists doubted the desirability of the motor carrier act of 1980 the purpose of this paper is to determine empirically whether the sweeping legislative changes were justified on solely economic grounds it is possible that previous cost studies are biased as a consequence of the regulatory constraints facing the firms has deregulation itself corrected for distortions created by the regulatory environment and thus produced changes in the production choices of trucking companies was friedlaender and spady s 7 contention that truckload carriers may have experienced regulatory rather than technology based increasing returns to scale correct if so perhaps past results for general freight carriers are similarly due to regulation however in this case the reason may be regulatory

human capital investment and labor supply under uncertainty we extend the theory of human capital investment under uncertainty by incorporating post investment labor supply as a choice variable we show that human capital investment decreases in response to an increase in risk about its return if such investment is an inferior activity and preferences exhibit decreasing risk aversion however if investment is normal then the effect of an increase in risk is indeterminate these results highlight the importance of obtaining empirical evidence on the income elasticity of demand for human capital investment for arriving at refutable hypotheses about the effect of risk

income instability and fiscal progression we construct the ratio of the post fisc transitory income variance to the pre fisc transitory income variance of family incomes as a measure of fiscal progressivity in canada between 1993 and 2008 this ratio can be interpreted as measuring the extent to which the fiscal system attenuates personal income instability we find that the tax and transfer system has been less eective in stabilizing market incomes after 1998 compared to the previous years this is attributable to the provincial and federal tax reforms from 1999 2001 which particularly aected families headed by individuals with less than high school education while the reforms reduced the eective marginal tax rates faced across all educational groups the reduction is relatively larger among families with highly educated main earners moreover the group with less than high school education is distinct in that the average eective tax burden in this group increased changes to social assistance also appear to have played a role

trends in men s earnings volatility what does the panel study of income dynamics show abstract many recent studies have investigated trends in u s men s earnings volatility but the studies based on the panel study of income dynamics appear to conflict with each other and with studies based on other data we critique some of the existing methods of measuring earnings volatility and we advocate for transparent methods that focus on simple measures of dispersion in year to year earnings changes applying such measures in the psid we find that apart from the well known counter cyclicality of earnings volatility men s earnings volatility increased during the 1970s but did not show a clear trend afterwards until a new upward trend appeared after 1998

uncertainty optimal taxation and the direct versus indirect tax controversy this paper examines how the presence of uncertainty affects the design of tax policy when both indirect taxes and a general income tax are available to the government there are two categories of goods the consumption levels in one group are committed to before the resolution of uncertainty and those of the other after the paper proves that contrary to a b atkinson and j e stiglitz s 1976 result differential commodity taxation remains a useful instrument of optimal tax policy even if preferences are separable between labor and produced goods copyright 1995 by royal economic society

deregulation and scale economies in the u s trucking industry an econometric extension of the survivor principle over the past three decades there has been much progress in the analysis of costs production and scale economies in u s industries including transportation and yet it can also be argued that accounting data on which all such cost and production function estimation is based do not give us a full story regarding scale economies in an industry among those who made this argument most forcefully was george stigler in a seminal article published in 1958 to provide evidence on scale economies with less use of accounting data stigler developed what he called the survivor technique a model that others have used in subsequent studies 1 the present article extends the survivor technique so as to make it a part of an econometric probit model somewhat akin to cost and production functions as they are estimated statistically but preserving the essential features of the survivor model developed by stigler in the 1950s the most important advantage of this approach is that it allows for the incorporation of a number of different variables to explain survivor

risky higher education and subsidies abstract tertiary education in the u s requires large investments that are risky lumpy and well timed tertiary education is also heavily subsidized our model suggests that despite adverse selection arising from encouraging poorly prepared students to enroll observed collegiate subsidies improve outcomes substantially relative to the fully decentralized case this result occurs because increases in subsidy rates for college education generate reductions in college failure risk without altering mean returns we find that this mechanism is robust and that tertiary subsidy rates well in excess of those observed in the u s can be justified by failure risk alone

welfare based income insecurity in the us and germany evidence from harmonized panel data this paper develops normative approaches for measuring individual level income insecurity using concepts derived from expected utility theory and prospect theory we build a suite of measures designed to capture various facets of psychologically distressing income risk we present an application for the us and germany from 1993 2013 employing conditionally heteroskedastic fixed effects models to generate predictive densities for future incomes our results reveal much higher levels of income risk in the us relative to germany which can be mostly attributed to a higher level of autonomous time invariant volatility state by state variations in liberal conservative political administrations partially explain our results and we find some evidence that trade exposure is a contributing factor in the us

returns to scale and market concentration among the largest survivors of deregulation in the us trucking industry application of the survivor technique to the 100 largest less than truckload carriers of general commodity freight in the us interstate trucking industry produces estimates of the ranges of increasing constant and decreasing returns to scale from 1981 to 1993 the first thirteen years of deregulation nearly one quarter of total group ton miles hauled is found to have moved into the more efficient size range of constant returns to scale a gain in long run technical efficiency is thereby attributed to the motor carrier act of 1980 moreover the survivorship data allow estimates of intragroup market concentration for each of the same thirteen post deregulation years concentration purely within this group appears to have remained fairly moderate and stable since 1981 an unsurprising finding given the modest minimum efficient size estimated at about 2 million ton miles hauled annually the moderate and stable concentration among the 100 largest is not necessarily incompatible with other research which

estimates of year to year volatility in earnings and in household incomes from administrative survey and matched data abstract we document trends in the volatility in earnings and household incomes between 1985 and 2005 in three different data sources administrative earnings records the survey of income and program participation sipp matched to administrative earnings records and sipp survey data in all data sources we find a substantial amount of year to year volatility in workers earnings and household incomes in the data sources that contain administrative earnings we find that volatility has been roughly constant and has even declined slightly since the mid 1980s these findings differ from what is found using survey data and what has been reported in previous studies

optimal wage and income taxation with wage uncertainty optimal taxation in a two period model with human capital investment and second period wage uncertainty is analyzed a proportional tax on wages dominates lump sum taxation and the socially optimal level of human capital exceeds that which individuals choose a tax on interest income may raise welfare by encouraging investment in human capital the interest income tax reduces the difference between returns to physical and human capital from individuals inability to reduce human capital risk through diversification a positive interest income tax rate may therefore be optimal even with an optimal wage tax by encouraging m ore investment in human capital copyright 1987 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

workers applications to social insurance programs when earnings and eligibility are uncertain a worker s decision whether to apply for public transfers may depend not only on his expected level of forgone labor earnings but also on his degree of uncertainty about such earnings this article provides theory and evidence about the effects of earnings and eligibility uncertainty on participation decisions the application rate to the social security disability insurance program is estimated to be about 15 higher than it would be in the absence of earnings risk as an application to tax policy optimal marginal wage tax rates may be higher than indicated in previous analyses involving wage uncertainty

earnings dynamics and inequality among canadian men 1976 1992 evidence from longitudinal income tax records using an extraordinary database drawn from longitudinal income tax records we decompose canada s growth in earnings inequality into its persistent and transitory components we find that the growth in earnings inequality reflects both an increase in long run inequality and an increase in earnings instability the canadian data strongly reject several restrictions commonly imposed in the u s literature and they also suggest that imposing these evidently false restrictions may lead to distorted inferences about earnings dynamics and inequality trends

changes in the distribution of earnings volatility recent research has documented a rise in the volatility of individual labor earnings in the united states since 1970 existing measures of this trend abstract from within group latent heterogeneity effectively estimating an increase in average volatility for observable groups we decompose this average and find no systematic rise in volatility for the vast majority of individuals increasing average volatility has been driven almost entirely by rising earnings volatility of those with the most volatile earnings identified ex ante by large past earnings changes we characterize dynamics of the volatility distribution with a nonparametric bayesian stochastic volatility model from jensen and shore 2011

growth effects of shifting from a graduated rate tax system to a flat tax i introduction recently the debate concerning fundamental u s tax reform has led to a number of proposals that involve a shift toward a consumption based system 1 one such proposal is the so called flat tax of hall and rabushka 1995 the flat tax would apply a single tax rate to all labor income above a given threshold and to all capital income after fully expensing investment expenditures hall and rabushka 1995 argue that the adoption of their proposal would provide an enormous boost to the u s economy by dramatically improving incentives to engage in productive activities and would save taxpayers hundreds of billions of dollars in compliance and administration costs 2 in this article we develop a quantitative general equilibrium model to assess the growth effects of adopting a flat tax plan similar to the one proposed by hall and rabushka 1995 the model captures many of the features of the current u s tax code such as graduated personal tax rates a standard personal deduction separate tax rates applied to personal and business income double taxation of business income and differential tax treatment of physical and human capital under appropriate parameter settings the model can exhibit either endogenous or exogenous long run growth our choice of functional forms facilitates a closed form solution to the model this allows us to characterize explicitly the economy s transition path following the reform a central issue in the debate over fundamental tax reform is the effect that such a reform would have on economic growth the present analysis builds on the work of stokey and rebelo 1995 who use an endogenous growth framework to identify the key model features and parameters that are important for determining the quantitative impacts of distortionary taxes on long run growth 3 our study differs from theirs and the bulk of the dynamic tax literature in one fundamental respect here we evaluate the growth effects of shifting from a graduatedrate tax system to a flat rate system stokey and rebelo 1995 consider only flat rate systems in which the marginal tax rate is equal to the average tax rate we approximate the graduated rate tax system in the u s economy by an empirical tax rate function that allows the personal tax rate to depend positively on household taxable income in equilibrium household decisions are influenced by both the level and slope of the tax schedule to implement the flat tax reform we shift the parameters of the tax rate function to flatten the marginal tax schedule while maintaining revenue neutrality our methodology treats the hall rabushka proposal as one that in effect moves a representative household from one tax rate schedule to another we view this setup as a reasonable approximation to gauge the growth effects of tax reform at the macro level a more elaborate setup would of course allow for household heterogeneity at a given point in time in this regard we note that caucutt et al 2003 have recently examined the growth effects of graduated rate taxes in a two period overlapping generations model that includes both skilled and unskilled agents in their model a flatter tax schedule increases the fraction of skilled agents in the economy the share of total output devoted to education rises accordingly and the economy s long run growth rate is observed to increase the quantitative implications of their model are difficult to compare to ours however because their two period framework implies a very long time horizon between household decisions about 30 years moreover their model abstracts from many of the features of the u s tax code that we include here in addition to examining the consequences of flattening the marginal tax schedule we investigate the growth effects attributable to other parts of the flat tax proposal such as allowing full investment expensing eliminating the double taxation of business income and increasing the standard personal deduction

consumption taxes and economic efficiency with idiosyncratic wage shocks fundamental tax reform is examined in an overlapping generations model in which heterogeneous agents face idiosyncratic wage shocks and longevity uncertainty a progressive income tax is replaced with a flat consumption tax if idiosyncratic wage shocks are insurable i e no risk this reform improves interim efficiency a result consistent with the previous literature but if more realistically wage shocks are uninsurable this reform reduces efficiency even though national wealth and output increase over the entire transition path this efficiency loss in large part stems from reduced intragenerational risk sharing that was previously provided by the progressive tax system

an equilibrium analysis of fiscal policy with uncertainty and incomplete markets insurance aspects of tax policies are studied in a simple intertemporal general equilibrium model in which agents are uncertain about both the future wage rates and the rate of return on capital taxation and lump sum subsidy policies generally reduce employment output and the capital stock but nonetheless they can be structured to provide pareto improvements on the incomplete market equilibrium these policies provide insurance against individual shocks not aggregate shocks examples of welfare maximizing tax schemes are provided using a simple computable general equilibrium model copyright 1993 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

uncertainty and optimally uniform commodity taxes this paper examines the implications of uncertainty for the structure of optimal commodity taxes in the presence of a linear income tax consumers face uncertain income and commit to consumption of some goods before the resolution of uncertainty and to others after preferences are separable between labor and consumption goods we prove that optimal commodity taxes are i uniform within the category of noncommitted goods if their subutility is logarithmic ii uniform within the two categories if both subutilities are logarithmic and iii nonzero across categories with the tax rate on precommitted goods being lower than the tax rate on noncommitted goods starting with atkinson and stiglitz 1976 a number of economists have argued that under certain restrictions on preferences e g logarithmic a linear income tax is a sufficient tool for optimal tax policy see atkinson 1977 deaton 1979 and deaton and stern 1986 recently cremer and gahvari 1995a showed that these results do not carry to an economy in which individuals face wage uncertainty in models with uncertainty taxation is useful for the insurance it provides if consumption takes place both before and after the resolution of uncertainty commodity taxes will have different insurance properties depending on when consumption occurs this property makes differential tax treatment of these two types of goods optimal cremer and gahvari 1995a divided commodities into two categories the consumption levels in one category are committed to before the resolution of uncertainty and those in the other after their study pinpoints a fundamental difference between these categories of goods that calls for their tax treatment to be different however their analysis leaves open the question of the uniformity of tax rates within each category the main aim of the current paper is to address this question we shall examine the type of preferences for which the tax rates within each category have to be uniform in this way we will build a bridge between the results of cremer and gahvari 1995a and the literature on uniform taxation in the presence of a linear