Alternative Estimates of the Effect of Family Structure during Adolescence on High School Graduation

Abstract

Many studies have reported significant empirical associations between family structure during childhood and children's outcomes later in life. It may be that living in a nonintact family has adverse consequences for children. On the other hand, it may be that some unobserved process jointly determines family structure and children's outcomes. How then should one interpret the empirical evidence on the relationship between family structure and children's outcomes? The answer depends on the question asked and on the prior information available to the researcher. We seek to interpret the association between family structure and high school graduation found among respondents in the National Longitudinal Study of Youth. We seek to answer the traditional question of the literature on treatment effects: How would the probability of high school graduation vary with family structure if family structure were not selected by parents but were, instead, an exogenously assigned “treatment,” as in a clinical trial or other controlled experiment? The inferential problem is that the data alone do not suffice to identify the treatment effect. Hence any attempt to estimate a treatment effect depends critically on the prior information available to the researcher. We develop alternative estimates of the effect of family structure on high school graduation, obtained under differing assumptions about the actual process generating family structure and high school outcomes. We first assume strong prior information and present estimates of a set of parametric latent-variable models explaining family structure and children's outcomes. We then assume no prior information at all and report estimates of nonparametric bounds on the graduation probabilities. Finally, we give non-parametric estimates obtained under the assumption that family structure is exogenous with respect to high school graduation. Our empirical analysis strengthens the evidence that living in an intact family increases the probability that a child will graduate from high school. We also report that the probability of high school graduation increases markedly with both parents’ education, regardless of family structure. At the same time, we stress that prior information is necessary if one is to do more than bound the effect of family structure on children's outcomes. Any point estimate embodies prior information about the process generating family structure and children's outcomes. As long as social scientists are heterogenous in their beliefs about this process, their estimates of family-structure effects may vary.