The "Window Problem" in Studies of Children'S Attainments : a Methodological Exploration

Numerous studies of the determinants of children's attainments rely on observations of circumstances and events at age 14 as proxies for information over the entire childhood period. Using 21 years of panel data from the Michigan PSID on 825 children who were 14-16 years old in 1979, we evaluate the effects of using truncated or "window" (e.g., age 14) information in models of the determinants of attainments (e.g., education, nonmarital fertility) of young adults. Correlations between truncated and full-childhood variables are presented, along with 5 tests of the reliability of estimates based on "window" measurements. The tests are designed to evaluate the differential effects of data accuracy, multiple occurrence of events, duration of circumstances, and the timing of events or circumstances during childhood between "window" and full childhood information. We conclude that most of the standard truncated variables serve as weak proxies for multi-year information in such models, and draw the implications of these findings for future data-collection and research