We develop and calibrate an overlapping generations general equilibrium model of the U.S. economy with heterogeneous consumers who face idiosyncratic earnings and health risk to study the implications of exogenous trends in increasing college attainment, decreasing fertility, and increasing longevity between 2005 and 2100. While all three trends contribute to a higher old age dependency ratio, increasing college attainment has different macroeconomic implications because it increases labor productivity. Decreasing fertility and increasing longevity require the government to increase the average labor tax rate from 32.0 to 44.4 percent. Increasing college attainment lowers the required tax increase by 10.1 percentage points. The required tax increase is higher under general equilibrium than in a small open economy with a constant interest rate because the reduction in the interest rate lowers capital income tax revenues.

Americans now work 50 percent more than do the Germans, French, and Italians. This was not the case in the early 1970s when the Western Europeans worked more than Americans. In this paper, I examine the role of taxes in accounting for the differences in labor supply across time and across countries, in particular, the effective marginal tax rate on labor income. The population of countries considered is that of the G-7 countries, which are major advanced industrial countries. The surprising finding is that this marginal tax rate accounts for the predominance of the differences at points in time and the large change in relative labor supply over time with the exception of the Italian labor supply in the early 1970s.

We ask what fraction of the variation in incomes across countries can be accounted for by investment distortions. In our neoclassical growth model the relative price of investment to consumption is a good measure of the distortions. Using data on relative prices we estimate a stochastic process for distortions and compare the resulting variance of incomes in the model to that in the data. We find that the variation of incomes in the model is roughly 4/5 of the variability of incomes in the data. Our model does well in accounting for 6 key regularities on income and investment in the data.

The paper itself is followed by three appendices: Appendix 1 describing the log-likelihood function, Appendix 2 describing the construction of labor share of income associated with the production of consumption and investment goods, and the Data Appendix.

This paper presents a simple model of government reputation which captures two characteristics of policy outcomes in less developed countries: governments which betray public trust do so erratically, and, after a betrayal, public trust is regained only gradually.

What shapes the optimal degree of progressivity of the tax and transfer system? On the one hand, a progressive tax system can counteract inequality in initial conditions and substitute for imperfect private insurance against idiosyncratic earnings risk. On the other hand, progressivity reduces incentives to work and to invest in skills, distortions that are especially costly when the government must finance public goods. We develop a tractable equilibrium model that features all of these trade-offs. The analytical expressions we derive for social welfare deliver a transparent understanding of how preference, technology, and market structure parameters influence the optimal degree of progressivity. A calibration for the U.S. economy indicates that endogenous skill investment, flexible labor supply, and the desire to finance government purchases play quantitatively similar roles in limiting optimal progressivity. In a version of the model where poverty constrains skill investment, optimal progressivity is close to the U.S. value. An empirical analysis on cross-country data offers support to the theory.

Although the role of financial constraints on entrepreneurial choices has received considerable attention, the effects of these constraints on aggregate capital accumulation and wealth inequality are less known. Entrepreneurship is an important determinant of capital accumulation and wealth concentration and, conversely, the distribution of wealth affects entrepreneurial choices in the presence of borrowing constraints. We construct a model that matches wealth inequality very well, for both entrepreneurs and non-entrepreneurs, and find that more restrictive borrowing constraints generate less wealth concentration, but also reduce average firm size, aggregate capital, and the fraction of entrepreneurs. We also find that voluntary bequests are an important channel that allows some high-ability workers to establish or enlarge an entrepreneurial activity: with accidental bequests only, there would be fewer large firms, fewer entrepreneurs, and less aggregate capital, but also less wealth concentration.

Entrepreneurship is a key determinant of investment, saving, and wealth inequality. We study the aggregate and distributional effects of several tax reforms in a model that recognizes this key role and that matches the large wealth inequality observed in the U.S. data. The aggregate effects of tax reforms can be particularly large when they affect small and medium-sized businesses, which face the most severe financial constraints, rather than big businesses. The consequences of changes in the estate tax depend heavily on the size of its exemption level. The current effective estate tax system insulates smaller businesses from the negative effects of estate taxation, minimizing the aggregate costs of redistribution. Abolishing the current estate tax would generate a modest increase in wealth inequality and slightly reduce aggregate output. Decreasing the progressivity of the income tax generates large increases in output, at the cost of large increases in wealth concentration.

We study optimal labor and capital taxation in a dynamic economy subject to government expenditure and aggregate productivity shocks. We relax two assumptions from Ramsey models: that a representative agent exists and that taxation is proportional with no lump-sum tax. In contrast, we capture a redistributive motive for distortive taxation by allowing privately observed differences in relative skills across workers. We consider two scenarios for tax instruments: (i) taxation is linear with arbitrary intercept and slope; and (ii) taxation is non-linear and unrestricted as in Mirrleesian models. Our main result provides conditions for perfect tax smoothing: marginal taxes on labor income should remain constant over time and invariant to shocks. In addition, capital should not be taxed. We also discuss implications for optimal debt management. Finally, an extension highlights movements in the distribution of relative skills as a potential source for variations in optimal marginal tax rates.

This paper studies optimal taxation of earnings when the degree of tax progressivity is allowed to vary with age. The setting is an overlapping-generations model that incorporates irreversible skill investment, flexible labor supply, ex-ante heterogeneity in the disutility of work and the cost of skill acquisition, partially insurable wage risk, and a life cycle productivity profile. An analytically tractable version of the model without intertemporal trade is used to characterize and quantify the salient trade-offs in tax design. The key results are that progressivity should be U-shaped in age and that the average marginal tax rate should be increasing and concave in age. These findings are confirmed in a version of the model with borrowing and saving that we solve numerically.

As part of compensation, municipal employees typically receive promises of future benefits. Motivated by the recent bankruptcy of Detroit, we develop a model of the equilibrium size of a city and use it to analyze how pay-with-promises schemes interact with city growth. The paper examines the circumstances under which a death spiral arises, where cutbacks of city services and increases in taxes lead to an exodus of residents, compounding financial distress. The model is put to work to analyze issues such as the welfare effects of having cities absorb pension risk and how unions affect the likelihood of a death spiral.