The Same School Rule, a Different Gender Payoff

The German evidence asks whether the life-cycle return to education depends on gendered family timing and institutions, even when the schooling shock looks familiar. Using a related school-starting-age cutoff, the study follows men and women through earnings, fertility, and employment around the first birth. The comparison supports a practical judgment: school-entry rules can be studied with a common causal logic, but their labor-market consequences cannot be transferred across countries without carrying along the direction of the treatment, the education system, the cohort, and the organization of motherhood.

One cutoff logic, two institutional designs

The California and German studies share a basic idea. People born close to an administrative cutoff are unlikely to differ systematically because of the exact day or month of birth, yet the rule assigns them different expected school-entry schedules. Researchers can compare outcomes on either side of that boundary and ask whether a discontinuity appears where the policy changes. This is the common causal intuition. It is not a claim that the two studies estimate the same treatment or draw from the same population.

In California, the relevant cohorts generally entered school earlier when they were born just before the December 1 or December 2 cutoff. The interaction between early entry and an age-based school-exit rule increased completed schooling, with the lasting response concentrated in some college. The main U.S. outcomes concern California-born mothers and their children: earnings, employment, occupations, job conditions, prenatal behavior, and birth outcomes.

West Germany used a different schedule. Depending on the state and cohort, common school-entry cutoffs included March 31, June 30, and December 31. Individuals born before a state-specific cutoff generally started school in the year they turned six; those born after it generally started in the year they turned seven. Thus, in the German study, being born after the cutoff generally made a person older at school entry and delayed entry into the labor market. More than 70 percent of children entered in the year scheduled by the rule, so the cutoff generated a substantial but imperfect shift in school starting age.

The schooling system added another important difference. After roughly four years of elementary school, German students were placed into basic, intermediate, or academic secondary tracks. The academic track prepared students for university, while the other tracks led more often toward apprenticeships and occupational routes. Compulsory schooling was grade-based rather than age-based. A later starter could therefore spend longer before entering work and still accumulate more education or reach a different track. The same policy variable—birthdate relative to a cutoff—interacted with a different institutional structure.

The German researchers use a 2 percent sample of people covered by the social-security system, with long labor-market biographies for West German citizens born from 1945 to 1965. An auxiliary National Educational Panel Study supplies information on actual school starting age and background characteristics that are absent from the main administrative records. The social-security sample covers much of the workforce but excludes civil servants and the self-employed. The California study has its own sample restrictions and data proxies.