Randomization In Testing Charter School Effectiveness (see correction)

Susan Dynarski had an interesting piece in the NYT on the relative effectiveness of charter schools in inner city and suburban neighborhoods. She reported on the findings from her own work, as well as others, that charter schools tend to result in higher achievement levels for inner city children, but had no effect on outcomes for children in suburban areas.

While this finding is interesting, it is important to note an important limitation to much of the research that has been done. Dynarski...