Research

This paper provides evidence that the added worker effect – labor force entry upon spousal job loss – is stronger for young than old households. Using a life cycle model of two-member households in a frictional labor market, we study whether this age-dependency is driven by heterogeneous needs for or availability of spousal insurance. Our framework endogenizes asset and human capital accumulation, as well as arrival rates of job offers, and is disciplined against U.S. micro data. Counterfactuals show a strong complementarity across both margins: A large added worker effect requires both high spousal earnings potential relative to the primary earner and limited access to other means of self-insurance. Together, both margins account for the observed age differential in the added worker effect. The model predicts substantial crowding out of spousal labor supply responses by unemployment benefit extensions among young households, in line with their stronger insurance motive.

We study the optimal design of means-tested transfers and progressive income taxes. In a simple analytical model, we show that adding a transfer to a log-linear tax induces welfare gains almost as large as in the second-best allocation. Transfers allow for more progressive average than marginal tax-and-transfer rates, achieving redistribution while preserving efficiency. In a rich dynamic model, we quantify the optimal fiscal plan. We use new flexible functions featuring targeted transfers and progressive income taxes, delivering a good empirical fit across the income distribution. Transfers should be larger than currently in the U.S. and financed with moderate income-tax progressivity.

We study the role of firm and worker level shocks for individual labor earnings dynamics. A key feature of the distribution of earnings changes is excess kurtosis, with substantial earnings changes for a significant proportion of workers. Using Danish matched employer-employee data, we show that large worker earnings changes occur along the entire firm revenue growth distribution but more frequently in the tails. In particular, large earnings losses are more likely in shrinking firms due to more employment separations and wage losses of stayers. We interpret the evidence through the lens of an equilibrium search model with two-sided heterogeneity. The model reveals that while worker shocks account for the majority of earnings fluctuations, firm shocks generate around a third of endogenous separations and large wage losses for stayers. Finally, the model implies significant endogenous responses of earnings dynamics to policy changes aiming to insure workers directly or indirectly through firms.

Over the last decades, the United States has experienced a large increase in, both, income inequality and living standards. The workhorse models of optimal income taxation call for more redistribution as inequality rises. By contrast, living standards play no role for taxes and transfers in these homothetic environments. This paper incorporates living standards into the optimal income tax problem by means of non-homothetic preferences. In a Mirrlees setup, we show that rising living standards alter both sides of the equity-efficiency trade-off. As an economy becomes richer, non-homotheticities imply a fall in the dispersion of marginal utilities, which weakens distributional concerns but has ambiguous effects on efficiency concerns. In a dynamic incomplete-market setup calibrated to the United States in 1950 and 2010, we quantify this new channel. Rising living standards dampen by around 30% the desired increase in redistribution due to rising inequality.