Evaluating Mobility Between Unmatched Quantiles: The Effects on Generational Mobility of Changes in Family Law in the United States

This paper addresses the intergenerational mobility question by examining the role of family structure in the transmission of educational attainment using the one percent Integrated Public Use Microsample Series (IPUMS) of the decennial Census for the decades 1970 and 1990. We first introduce mobility indices and tests which examine the proximity of the transition matrix to that which would pertain in the perfectly mobile state. Unlike existing transition matrix based mobility indices, these indices and tests can be employed when the quantiles of the marginal states are unmatched, and when the transition matrix is between states that are defined multivariately. Using educational attainment as a proxy for permanent income for children and both educational attainment and income as proxies for parents, the tests indicate that mobility significantly increased for the population as a whole. Within the single parent group there was much less evidence for significant mobility change for children from widowed single parent families than for children from divorced and separated single parent families. There is also some evidence of convergence between intact and, divorced and separated parent families, suggesting that there is a trend towards equal opportunity.