We conduct a systematic empirical study of cross-sectional inequality in the United States, integrating data from the Current Population Survey, the Panel Study of Income Dynamics, the Consumer Expenditure Survey, and the Survey of Consumer Finances. In order to understand how different dimensions of inequality are related via choices, markets, and institutions, we follow the mapping suggested by the household budget constraint from individual wages to individual earnings, to household earnings, to disposable income, and, ultimately, to consumption and wealth. We document a continuous and sizable increase in wage inequality over the sample period. Changes in the distribution of hours worked sharpen the rise in earnings inequality before 1982, but mitigate its increase thereafter. Taxes and transfers compress the level of income inequality, especially at the bottom of the distribution, but have little effect on the overall trend. Finally, access to financial markets has limited both the level and growth of consumption inequality.

Macroeconomics is evolving from the study of aggregate dynamics to the study of the dynam-ics of the entire equilibrium distribution of allocations across individual economic actors. This article reviews the quantitative macroeconomic literature that focuses on household hetero-geneity, with a special emphasis on the “standard ” incomplete markets model. We organize the vast literature according to three themes that are central to understanding how inequality matters for macroeconomics. First, what are the most important sources of individual risk and cross-sectional heterogeneity? Second, what are individuals ’ key channels of insurance? Third, how does idiosyncratic risk interact with aggregate risk? *This paper was prepared for Volume 1 of the Annual Review of Economics. Heathcote and Violante thank the National Science Foundation (Grant SES-0418029). The views expressed herein are those of the authors and not necessarily those of the Federal Reserve Bank of Minneapolis or the Federal Reserve System. 1

Using a model with constant relative risk-aversion preferences, endogenous labor supply and partial insurance against idiosyncratic wage risk, the paper provides an analytical characterization of three welfare effects: (a) the welfare effect of a rise in wage dispersion, (b) the welfare gain from completing markets, and (c) the welfare effect from eliminating risk. Our analysis reveals an important trade-off for these welfare calculations. On the one hand, higher wage uncertainty increases the cost associated with missing insurance markets. On the other hand, greater wage dispersion presents opportunities to raise aggregate productivity by concentrating market work among more productive workers. Our welfare effects can be expressed in terms of the underlying parameters defining preferences and wage risk or, alternatively, in terms of changes in observable second moments of the joint distribution over individual wages, consumption and hours.

This paper uses an estimated structural model to argue that the option to move in and out of the parental home is an important insurance channel against labor market risk for lowskilled youths. Using data from the NLSY97, I construct a new monthly panel of parent-youth coresidence outcomes and use it to document an empirical relationship between these movements and individual labor market events. The data is then used to estimate the parameters of a dynamic game between youths and their altruistic parents, featuring coresidence, labor supply and savings decisions. Parents can provide both monetary support through explicit …nancial transfers, and non-monetary support in the form of shared residence. To account for the data, two types of exogenous shocks are needed. Preference shocks are found to explain most of the cross-section of living arrangements, while labor market shocks account for individual movements in and out of the parental home. I use the model to show that coresidence is an important form of insurance, particularly for youths from poorer families. The option to live at home also helps to explain features of aggregate data for low-skilled young workers: their high elasticity of labor supply and their relatively small consumption responses to labor market shocks. An important

Previous papers have tested efficient risk sharing under the assumption of identical risk preferences. In this paper we show that, if in the data households have heterogeneous risk preferences, the tests proposed in the past reject efficiency even if households share risk efficiently. To address this issue we propose a method that enables one to test efficiency even when households have different preferences for risk. The method is composed of three tests. The first one can be used to determine whether in the data under investigation households have homogeneous risk preferences. The second and third test can be used to evaluate efficient risk sharing when the hypothesis of homogeneous risk preferences is rejected. We use this method to test efficient risk sharing in rural India. Using the first test, we strongly reject the hypothesis of identical risk preferences. We then test efficiency with and without the assumption of preference homogeneity. In the first case we reject efficient risk sharing at the village and caste level. In the second case we still reject efficiency at the village level, but we cannot reject this hypothesis at the caste level. This finding suggests that the relevant risk-sharing unit in rural India is the caste and not the village. 1

I study efficient allocations in a dynamic private information economy with a continuum of individual shocks that are persistent. I formulate the problem recursively and develop a first order approach to simplify it. The main advantage of the first order approach is that it allows for a substantial reduction of the state space of the dynamic program. This makes the problem tractable and permits quantitative implementation of the problem. I provide both qualitative and quantitative solutions for a taste shock economy where the shocks follow a random walk. I show that insurance against the shocks works very differently than in an otherwise identical economy with i.i.d. shocks. Both current and continuation utility are now positively correlated with the current shock and the social planner will optimally overinsure the agents, rather than underinsure. Also, for most of the population the intertemporal wedges are significantly larger than in an i.i.d. economy.

This paper investigates the sources of cross-sectional di¤erences in consumption, labor supply, wealth and welfare over the lifecycle. I document the existence of rich and informative lifecycle patterns in the joint distribution of wages, hours, consumption and wealth. I then estimate a structural model of precautionary savings with endogenous labor supply and uninsurable wage risk in an attempt to assess the ability of the standard incomplete markets model to simultaneously account for the various dimensions of lifecycle inequality. I find that in many dimensions the model provides a coherent explanation. However, the combination of certain features of the data provides an inherent challenge for this class of models. Structural estimates of parameter values are obtained using Monte-Carlo Markov Chain techniques. These are then used to decompose inequality at different points in the lifecycle into differences in preferences, differences in initial wealth endowments, differences in fixed labor productivity and the accumulated e¤ects of shocks realized after entry to the labor market. I find that around 40 % of the cross-sectional differences in lifetime welfare are due to fixed skills and around 60 % are due to lifecycle productivity shocks. Differences in financial wealth endowments, however, account for almost none of the inequality in lifetime welfare.

How well do people share risk? Standard risk-sharing regressions assume that any variation in households ’ risk preferences is uncorrelated with variation in the cyclicality of income. I combine administrative and survey data to show that this assumption is questionable: Risk-tolerant workers hold jobs where earnings carry more aggregate risk. The correlation makes risk-sharing regressions in the previous literature too pessimistic. I derive techniques that eliminate the bias, apply them to U.S. data, and find that the effect of idiosyncratic income shocks on consumption is practically small and statistically difficult to distinguish from zero.

Based on well-known evidence on labor supply elasticities, several authors have concluded that women should be taxed at lower rates than men. We evaluate the quantitative implications of taxing women at a lower rate than men. Relative to the current system of taxation, setting a proportional tax rate on married females equal to 4 % (8%) increases output and married female labor force participation by about 3.9 % (3.4%) and 6.9 % (4.0%), respectively. Gender-based taxes improve welfare and are preferred by a majority of households. Nevertheless, welfare gains are higher when the U.S. tax system is replaced by a proportional, gender-neutral income tax.

(ii) development of