Evaluations of educational programs or interventions are typically conducted in nonrandomly selected samples of schools or districts. Recent research has shown that nonrandom site selection can yield biased impact estimates. To estimate the external validity bias from nonrandom site selection, we combine lists of school districts that were…

Care Quality Rating and Improvement Systems (QRISs) have advanced and matured, a number of states and localities have undertaken evaluations to validate the systems. Such efforts stem from the desire to ensure that the system is designed and operating in the ways envisioned when the system was established. Given that a central component in a QRIS…