We provide the first systematic account of summer declines in women's labor market activity. From May to July, US women's employment-to-population ratio declines 1.1pp, whereas men's rises; women's hours worked fall 9.8%, twice the decline among men. School closures for summer break provide a unifying explanation. The summer drop aligns with cross-state differences in school closure timing, is concentrated among mothers with young school-aged children, and coincides with increased time spent on childcare. Gender differences both within and across jobs explain gender gaps in summer exits from employment. Women's summer work interruptions contribute to gender gaps in pay.

In nonlinear panel data models, fixed-effects methods are often criticized because they cannot identify average marginal effects (AMEs) in short panels. In contrast with that criticism, we prove the point identification of different AMEs, including causal effects of changes in the lagged dependent variable or the last choice's duration, in a panel dynamic logit model for T as small as three. Our proofs are constructive and provide simple closed-form expressions for the AMEs in terms of probabilities of choice histories. We illustrate our results using Monte Carlo experiments and with an empirical application of a dynamic model of consumer brand choice.

India is home to a comprehensive affirmative action program that reserves a fraction of positions at governmental institutions for various disadvantaged groups. While there is a Supreme Court-endorsed mechanism to implement these reservation policies when all positions are identical, courts have refrained from endorsing explicit mechanisms when positions are heterogeneous. This lacuna has resulted in widespread adoption of unconstitutional mechanisms, countless lawsuits, and inconsistent court rulings. By formulating mandates from the landmark Supreme Court judgment Saurav Yadav vs The State of U.P. (2020) as technical axioms, we show that the 2SMH-DA mechanism is uniquely suited to overcome these challenges.

Gravity equations are an important tool in empirical international trade research. We study to what extent sector-level parameters can be recovered from aggregate gravity equations estimated via Poisson pseudo maximum likelihood. We show that in the leading case where trade cost regressors do not vary at the sector level, estimates obtained with aggregate data have a clear interpretation as a weighted average of sectoral elasticities. Otherwise the estimates are biased, but researchers may possibly infer the direction of the bias. We illustrate our results by revisiting Baier and Bergstrand’s (2007) influential study of the effects of free trade agreements.

Exponential regressions are frequently used when outcomes are non-negative. They are attractive because they are easy to interpret and to estimate, using pseudo maximum likelihood (PML). However, the validity of these methods depends on the correct specification of the conditional expectation, and little is known regarding their properties when the conditional expectation is misspecified. We show that PML estimators of misspecified exponential models provide optimal approximations to the conditional expectation, in a weighted mean squared error sense, and we give conditions under which their Poisson PML estimator identifies average marginal effects.

We measure trends in affective polarization in twelve OECD countries over the past four decades. According to our baseline estimates, the United States experienced the largest increase in polarization over this period. Five countries experienced a smaller increase in polarization. Six countries experienced a decrease in polarization. We relate trends in polarization to trends in potential explanatory factors.

We connect two large bodies of scientific inquiry. First, important theories in the social sciences establish that human preferences are reference-dependent. Second, a separate field of research documents substantial differences in preferences and attitudes across genders. Specifically, we examine the universe of official classic chess games (more than 250,000 subjects and 22 million games). This allows us to study differences across genders both in cognitive performance (intensive margin) and in competitive participation (extensive margin), using the fact that personal bests act as reference points. We find that males and females behave very differently around their personal bests in both margins.

We present new findings about the relationship between marriage and socioeconomic background in the United States in the late 19th and early 20th centuries. Imputing socioeconomic status of family of origin from first names, we document a socioeconomic gradient for women in the probability of marriage and the socioeconomic status of husbands, which widens over this period. Regional divergence in occupational structure explains half of the divergence in the probability of marriage, and most of the increase in marital sorting. Urbanization and the associated improvement in women's labor market opportunities drive most of these differences.

We document that the real effects of monetary shocks last for over a decade. Our approach relies on (1) identification of exogenous and non-systematic monetary shocks using the trilemma of international finance; (2) merged data from two new international historical cross-country databases; and (3) econometric methods robust to long-horizon inconsistent estimates. Notably, the capital stock and total factor productivity (TFP) exhibit greater hysteresis than labor. When we allow for asymmetry, we find these effects with tightening shocks, but not with loosening shocks. When extending the horizon of the responses reported in several recent studies that use alternative monetary shocks, we find similarly persistent real effects, thus supporting our main findings.

We analyze optimal vaccine subsidies in a model integrating disease epidemiology into a market with rational economic agents. The focus is on an intensive vaccine campaign to quell an epidemic in the short run. Across a range of market structures, positive vaccine externalities and optimal subsidies peak for diseases that spread quickly, but not so quickly that everyone is driven to be vaccinated. We assess the practical relevance of this peak—as well as the existence of increasing social returns to vaccination and optimality of universal vaccination—in calibrations to the COVID-19 pandemic.