This working paper examines the sensitivity and precision of teacher value-added model (VAM) estimates obtained under model specifications that differ based on whether they include student-level background characteristics, peer-level background characteristics, and/or a double-lagged achievement...

This note demonstrates that in applied regression analysis, the variance of a coefficient of interest may decrease from the inclusion of a control variable, contrasting with Clarke’s assertion (2005, 2009) that the variance can only increase or stay the same. Practitioners may thus be...