UC Santa Cruz

When education programs are renewed yearly, participation in such programs can vary over time, resulting in multiple patterns of participation. One such example is the national Head Start program administered for two consecutive years, serving children aged 3 and 4. Even though there are four possible patterns of Head Start attendance, Head Start has often been examined as a one-time event in early childhood education literature, with only the effect of early Head Start attendance at age 3 being evaluated. In this study, we propose to apply causal mediation analysis to the study of yearly renewable education programs, separating the effect of initial program attendance into sequential effects of the programs over time and long-term effects of initial program attendance. We adopt a parametric closed-form estimation that combines regression models to examine the effect of Head Start on children’s receptive vocabulary using data from the Head Start Impact Study as an illustration. Our analysis exemplifies how the effect of a yearly renewable education program can be attributed to different program attendance histories and invites further research on studying time-varying treatment effects as causal mediation effects.