
Na’ama Shenhav
Senior Economist
Microeconomic Research
Labor economics, Gender, Education
CV (pdf, 60.59 kb)
Profiles: Personal website
Working Papers
Long-Run Effects of Incentivizing Work After Childbirth
NBER 27444 | with Kuka | June 2020
abstract (+)This paper uses a panel of SSA earnings linked to the CPS to estimate the impact of increasing post-childbirth work incentives on mothers’ long-run career trajectories. We implement a novel research design that exploits variation in the timing of the 1993 reform of the Earned Income Tax Credit (EITC) around a woman’s first birth and in eligibility for the credit. We find that single mothers exposed to the expansion immediately after a first birth (“early-exposed”) have 3 to 4 p.p. higher employment in the 5 years after a first birth than single mothers exposed 3 to 6 years after a first birth (“late-exposed”). Ten to nineteen years after a first birth, early-exposed mothers have the same employment and hours as late-exposed mothers, but have accrued 0.5 to 0.6 more years of work experience and have 6 percent higher earnings. Incorporating long-run effects on EITC benefits and earnings increases the implied marginal value of public funds (MVPF) of the expansion. Our results suggest that there are steep returns to work incentives at childbirth that accumulate over the life-cycle.
Published Articles (Refereed Journals and Volumes)
Selection into Identification in Fixed Effects Models with Application to Head Start
Forthcoming in Journal of Human Resources | with Miller and Grosz
abstract (+)Many papers use fixed effects (FE) to identify causal impacts of an intervention. When
treatment status only varies within some FE groups (e.g., families, for family fixed effects), FE
can induce non-random selection of groups into the identifying sample, which we term selection
into identification (SI). This paper empirically documents SI in the context of several family fixed
effects (FFE) applications with a binary treatment. We show that the characteristics of the FFE
identifying sample are different than the overall sample (and the policy-relevant population),
including having larger families. The main implication of this is that when treatment effects
are heterogeneous, the FE estimate may not be representative of the average treatment effect
(ATE). We show that a reweighting-on-observables FE estimator can help recover the ATE
for policy-relevant populations, and recommend its use either as a primary estimator or as a
diagnostic tool to assess the importance of SI. We apply these insights to re-examine the long-term effects of Head Start in the PSID and the CNLSY using FFE. When we reweight the FFE
estimates, we find that Head Start leads to a 2.6 percentage point (p.p.) increase (s.e. = 6.2
p.p.) in the likelihood of attending some college for white Head Start participants in the PSID.
This participants’ ATE is 78% smaller than the traditional FFE estimate (12 p.p). We also find
that the CNLSY Head Start participants’ ATE is smaller than the FE estimates. This raises
new concerns with the external validity of FE estimates.
Selection into Identification in Fixed Effects Models, with Application to Head Start
Forthcoming in Journal of Human Resources | with Miller and Grosz
abstract (+)Many papers use fixed effects (FE) to identify causal impacts of an intervention. In this paper we show that when the treatment status only varies within some groups, this design can induce non-random selection of groups into the identifying sample, which we term selection into identification (SI). We begin by illustrating SI in the context of several family fixed effects (FFE) applications with a binary treatment variable. We document that the FFE identifying sample differs from the overall sample along many dimensions, including having larger families. Further, when treatment effects are heterogeneous, the FFE estimate is biased relative to the average treatment effect (ATE). For the general FE model, we then develop a reweighting-on-observables estimator to recover the unbiased ATE from the FE estimate for policy-relevant populations. We apply these insights to examine the long-term effects of Head Start in the PSID and the CNLSY. Using our reweighting methods, we estimate that Head Start leads to a 2.6 percentage point (p.p.) increase (s.e. = 6.2 p.p.) in the likelihood of attending some college for white Head Start participants in the PSID. This ATE is 78% smaller than the traditional FFE estimate (12 p.p). Reweighting the CNLSY FE estimates to obtain the ATE produces similar attenuation in the estimated impacts of Head Start.
Women’s Suffrage and Children’s Education
American Economic Journal: Economic Policy 13(3), August 2021, 374-405 | with Kose and Kuka
abstract (+)While a growing literature shows that women, relative to men, prefer greater investment in children, it is unclear whether empowering women produces better economic outcomes. Exploiting plausibly exogenous variation in U.S. suffrage laws, we show that exposure to suffrage during childhood led to large increases in educational attainment for children from disadvantaged backgrounds, especially Blacks and Southern Whites. We also find that suffrage led to higher earnings alongside education gains, although not for Southern Blacks. Using newly digitized data, we show that education increases are primarily explained by suffrage-induced growth in education spending, although early-life health improvements may have also contributed.
Lowering Standards to Wed? Spouse Quality, Marriage, and Labor Market Responses to the Gender Wage Gap
The Review of Economics and Statistics 103(2), May 2021, 265-279
abstract (+)This paper examines the effect of the female-to-male wage ratio, “relative wage,” on women’s spouse quality, marriage, and labor supply over three decades. Exploiting task-based demand shifts as a shock to relative pay, I find that a higher relative wage (a) increases the quality of women’s mates, as measured by higher spousal education; (b) reduces marriage without substitution to cohabitation; and (c) raises women’s hours of work. These effects are consistent with a model in which a higher relative wage increases the minimum nonpecuniary benefits (“quality”) women require from a spouse and therefore reduce marriage among low-quality husbands.
A Century of the American Woman Voter: Sex Gaps in Political Participation, Preferences, and Partisanship Since Women’s Enfranchisement
Journal of Economic Perspectives 34(2), Spring 2020, 24-48 | with Cascio
abstract (+)This year marks the centennial of the Nineteenth Amendment, which provided American women a constitutional guarantee to the franchise. We assemble data from a variety of sources to document and explore trends in women’s political participation, issue preferences, and partisanship since that time. We show that in the early years following enfranchisement, women voted at much lower rates than men and held distinct issue preferences, despite splitting their votes across parties similarly to men. But by the dawn of the twenty-first century, women not only voted more than men, but also voted differently, systematically favoring the Democratic party. We find that the rise in women’s relative voter turnout largely reflects cross-cohort changes in voter participation and coincided with increasing rates of high school completion. By contrast, women’s relative shift toward the Democratic party permeates all cohorts and appears to owe more to changes in how parties have defined themselves than to changes in issue preferences. The findings suggest that a confluence of factors have led to the unique place women currently occupy in the American electorate, one where they are arguably capable of exerting more political influence than ever before.
Do Human Capital Decisions Respond to the Returns to Education? Evidence from DACA
American Economic Journal: Economic Policy 12(1), February 2020, 293-324 | with Kuka and Shih
abstract (+)This paper studies human capital responses to the availability of the Deferred Action for Childhood Arrivals (DACA) program, which provides temporary work authorization and deferral from deportation for undocumented, high-school-educated youth. We use a sample of young adults that migrated to the United States as children to implement a difference-in-difference design that compares noncitizen immigrants (“eligible”) to citizen immigrants (“ineligible”) over time. We find that DACA significantly increased high school attendance and high school graduation rates, reducing the citizen-noncitizen gap in graduation by 40 percent. We also find positive, though imprecise, impacts on college attendance.
A Reason to Wait: The Effect of Legal Status on Teen Pregnancy
American Economic Association Papers and Proceedings 109, May 2019, 213-217 | with Kuka and Shih
abstract (+)Although teen pregnancy has been on the decline in the United States, it remains among the highest within developed countries. Hispanics, who are more likely to be undocumented immigrants, lead this trend, yet the role of legal status has yet to be considered. To investigate this question, we examine teenage fertility responses to the Deferred Action for Childhood Arrivals (DACA) program, which provides temporary legal status to undocumented youth. We find that DACA reduced the likelihood of having a teenage birth by 1.6 percentage points and eliminated roughly half of the gap in teenage childbearing between documented and undocumented women.