As a result of the use of random assignment to treatment, randomized experiments typically have high internal validity. However, units are very rarely randomly selected from a well-defined population of interest into an experiment; this results in low external validity. Under nonrandom sampling, this means that the estimate of the sample average…

Although brief experimental analysis (BEA) procedures have been effective for aiding instructional decision making in the area of reading, there is a paucity of research extending this technology to mathematics. This study extends the literature on mathematics BEA by using an abridged data series that compares skill- and performance-based…