An Inter-Cohort Comparison of Intra-Cohort Social Stratification: How Do Cumulative Dis/Advantages Evolve Across Cohorts?

The aim of our paper is to analyze trajectories in hourly wages between the ages of 30 and 50 for five different birth cohorts, using the PSID data. More precisely, we focus on processes of intra-cohort stratification by tracing patterns of income as individuals age. Our analysis is informed by the cumulative dis/advantage hypothesis as a process of intra-cohort stratification. Using growth curve models, we seek to describe and explain the patterns of income stratification within and between cohorts. We hypothesize two key patterns: Simple interindividual divergence and path-dependent interindividual divergences. Simple interindividual divergence is indicated when the relation between initial hourly wage and its slope over time is positive (in contrast to convergence, where this relation is negative, and stability, where there is no relation between initial hourly wage and its slope over time). Path-dependent interindividual divergence is indicated when hourly wage differences between men and women, or between whites and non-whites, increase as individuals age. Our analyses will reveal if the patterns of wage divergence over the life course are constant across cohorts, or whether the extent and form of wage divergence is shifting over time.