Research has shown that higher maternal and paternal age is positively associated with children's education. Debate continues as to whether these relationships are causal. This is of great interest given the postponement of first births in almost all developed countries during the twentieth century. Here we use an instrumental variable approach (Mendelian randomization) using maternal and paternal polygenic indices (PGIs) for age at first birth-while conditioning on the child's PGI for age at first birth-to identify the causal effects of maternal and paternal age at first birth on children's test scores based on data from the Norwegian Mother, Father and Child Cohort study. We do not find evidence of positive causal effects of both maternal and paternal age at first birth on children's test scores at age 10 years once the children's PGI and correlations among different PGIs are controlled for. We therefore conclude that our results do not provide evidence in favour of sociological theories that predict positive causal effects of parental age on children's educational attainment.

Equality of opportunity is a principle of social justice, although there are different conceptions of it. We distinguish between liberal and radical (in)equality of opportunity. Both conceptions consider unfair inequalities in life outcomes that result from ascribed characteristics such as social origin, migration background, and sex. However, they differ in that liberal inequality of opportunity considers it fair when natural talents affect life outcomes. Conversely, radical inequality of opportunity places natural talents in the category of morally arbitrary factors that do not provide a fair basis for inequalities in life outcomes. We use polygenic indices (PGIs) to better disentangle the role of natural talents from the roles of ascribed characteristics and individual choices. We compare using PGIs to using measures of skills observed later in life. We apply this approach to two survey datasets, (i) the Wisconsin Longitudinal Study and (ii) the German Socio-Economic Panel Study. According to our results, radical inequality of opportunity is considerably larger than liberal inequality of opportunity, especially for education. Measuring natural talents using PGIs leads to very similar conclusions as using skills measured later in life. However, the differences between liberal and radical inequality of opportunity are smaller using PGIs than using measures of observed skills.

Previous research found that increasing the age at first tracking in an education system increased educational mobility. This research has implicitly assumed that these effects do not vary across contexts. Contrary to this assumption, we develop two hypotheses predicting such variation. The first hypothesis predicts that changes in the age at tracking increase educational mobility more for larger than for smaller changes in the age at tracking. According to the second hypothesis, reforms in the age at tracking only increase educational mobility if they occur in societies which put a high emphasis on equality of opportunity as a policy aim. We test these hypotheses by estimating the effects of reforms in the age at tracking, which occurred in five European countries (Belgium, Denmark, Finland, France, and Italy) in the 20th century, on educational mobility. We use data from the European Social Survey (ESS) and the Survey of Health, Ageing and Retirement in Europe (SHARE). The effects of the reforms are identified using a regression discontinuity design (RDD). A third hypothesis tests if the reforms increase educational mobility more among women than among men and if this is particularly the case in countries with a more gender egalitarian climate. Overall, the results reveal little cross-country variation in the effects of reforms in the age at tracking on educational mobility. In all analyzed countries there is an increase in educational mobility due to the reform in the age at tracking. In most countries, these effects do not differ between men and women. 

The notion of equality of opportunity has motivated different empirical approaches. However, not all empirical approaches to measure equality of opportunity have been motivated by the same conception of equality of opportunity. This book chapter distinguishes between two conceptions of equality of opportunity, liberal and radical equality of opportunity, and relates them to empirical approaches that aim at measuring equality of opportunity: research on intergenerational mobility, measures of sibling similarities, surname mobility, and the equality of opportunity measurement advanced by John Roemer. The chapter concludes with some directions for further research, suggesting that (1) empirical research should measure and compare both liberal and radical equality of opportunity and (2) more empirical progress will come about by combining the different approaches to measure equality of opportunity.

The diverging destinies hypothesis predicts that educational inequality increases in contemporary societies because parents with higher levels of education postpone the birth of their children. This hypothesis is supported by empirical evidence demonstrating that advanced parental ages improve children’s educational outcomes. However, the consequences of socioeconomic differences in parental ages for the intergenerational transmission of education also depend on whether the associations between parental ages and child education vary by parental education. To test this hypothesis, we use data from three countries representing different welfare regimes: Germany, Norway, and the United States. In all three countries, children’s educational attainment at the secondary school level increases with higher parental ages more in families with low than in families with highly educated parents. In other words, the intergenerational transmission of education is stronger for younger than for older parents. Consequently, our findings nuance the diverging destinies hypothesis by demonstrating that increasing parental ages in socioeconomically disadvantaged families increases educational mobility more than decreasing parental ages in socioeconomically advantaged families. These findings are qualitatively the same in all three countries, suggesting that diverging destinies also occur in countries outside the United States.

Parental separation is associated with a range of negative outcomes for children experiencing it, and there is ongoing scholarly and public interest in whether these associations reflect causal effects of parental separation. We estimate the effect of parental separation on children's educational achievement in Sweden using the proportion of male colleagues at the maternal workplace as an instrumental variable for parental separation. We discuss our instrumental variable approach in the context of the literature on the heterogeneous effects of parental separation. In the empirical analysis, we use population register data on 387,411 Swedish children born between 1990 and 1996 and measure educational achievement through their grade point averages in the final year of compulsory schooling. We find that parental separation does not have a negative effect on educational achievement and that this result is robust across a range of specifications. We argue that our results are informative of the effects of a large share of parental separations, in which parents dissolve relatively well-functioning unions.

This study estimates the effects of women's education on their offspring using quasi-experimental evidence from six educational reforms that increased the length of compulsory schooling in several European countries. The empirical analysis uses data from the Survey of Health, Ageing and Retirement in Europe and instrumental variable estimation to estimate the effects of female education on fertility and on children's education. This study provides the first analysis using quasi-experimental variation in education to estimate prospective models of intergenerational effects. These models start with a birth cohort and link information on their fertility and on their children's outcomes. These models account for the effect of female education on the probability that women have children when estimating the effect of female education. The direct effect of female education on children's educational attainment, i.e. the effect conditional on the birth of a child, is positive. In addition, higher female education increases fertility. Therefore, the probability that a woman has a child with a high educational attainment is increased when considering the effect of female education on fertility. Studies that estimate retrospective models of intergenerational effects using reforms in the length of compulsory schooling may underestimate the total effect of female on child education.

Critical theories of education and the dynamics of skill formation model predict that the education system reproduces socioeconomic inequalities in educational attainment. Previous empirical studies comparing changes in socioeconomic inequalities in academic performance over the summer to changes in these inequalities during the school year have argued, however, that schooling reduces inequalities in educational performance. The present study highlights the question of whether schooling affects socioeconomic inequalities in educational attainment by analyzing a natural experiment that induces exogenous variation in the length of schooling and allowed me to investigate the causal, long-term effects of the length of schooling on inequalities in educational attainment. Some German states moved the school start from spring to summer in 1966/1967 and introduced two short school years, each of which was three months shorter than a regular school year. I use variation in the short school years across cohorts and states to estimate the causal effects of the length of schooling on socioeconomic inequalities in educational attainment based on two German panel surveys. Less schooling due to the short school years did not affect inequalities in educational attainment. This finding runs counter to the results from the summer learning literature and to the predictions of the dynamics of skill formation model and critical theories of education. I conclude by discussing the implications of this finding for our understanding of socioeconomic inequalities in educational attainment.

The mechanisms linking parental resources to their children’s opportunities are of fundamental interest to sociologists. This study is the first to provide a dynamic life course assessment of the origin–education–destination triangle using causal mediation analysis. While the age-as-equalizer hypothesis suggests that for the highly educated, direct effects of social origin are high at young ages and decrease over the life course, the age-as-stratifier hypothesis suggests that for individuals with low educational attainment, direct effects of social origin are low at young ages and increase over the life course. Findings using panel data from the German Socio-Economic Panel Study are largely consistent with these hypotheses for various measures of social origin and social destination. Overall, this study demonstrates how causal mediation analysis provides precise effect definitions that allow scholars to assess mechanisms when status transmission processes depend on educational attainment.

There is a growing interest in how social conditions moderate genetic influences on education [gene–environment interactions (GxE)]. Previous research has focused on the family, specifically parents’ social background, and has neglected the institutional environment. To assess the impact of macro-level influences, we compare genetic influences on educational achievement and their social stratification across Germany, Norway, Sweden, and the United States. We combine well-established GxE-conceptualizations with the comparative stratification literature and propose that educational systems and welfare-state regimes affect the realization of genetic potential. We analyse population-representative survey data on twins (Germany and the United States) and twin registers (Norway and Sweden), and estimate genetically sensitive variance decomposition models. Our comparative design yields three main findings. First, Germany stands out with comparatively weak genetic influences on educational achievement suggesting that early tracking limits the realization thereof. Second, in the United States genetic influences are comparatively strong and similar in size compared to the Nordic countries. Third, in Sweden genetic influences are stronger among disadvantaged families supporting the expectation that challenging and uncertain circumstances promote genetic expression. This ideosyncratic finding must be related to features of Swedish social institutions or welfare-state arrangements that are not found in otherwise similar countries.