Charter school study

The contents here is from the website: School Finance 101

Data and thoughts on public and private school funding in the U.S. Thoughts on “Randomized” vs. Randomized Charter School Studies

What is a truly “randomized” and “experimental” study? This study aims to determine the effect that “charter schooling” has on students’ outcomes, when compared to kids who don’t receive the strategies about “charter schooling”. There tend to be two types of studies done to determine this relative effectiveness of “charter schools” versus traditional “district schools.” Students who went to “charter schooling” are called treatment group. The students who did not go are called the control group.

One study tried to identify after the fact, otherwise similar kids (matched pairs) attending a set of charter schools and a set of district schools in the same city, and then compared their achievement growth over time. There are two shortfalls for this type of study. First, the measures used to determine which kids are comparable, or paired, are often too crude to ensure that kids really are similar. Second, while kids in charter and district schools are matched with one another on these crude characteristics, the settings in which they are schooled, including the mix of peers with which they attend school may be dramatically different.

The other study is referred to as meeting the gold standard – as being a randomized study – or lottery-based study. First, what would a randomized study look like? Well, it would have to look something like this – where we randomly take a group of kids – with consent or even against their will – and assign them to either the charter or traditional school option. The mix of kids in each group is truly random and checked to ensure that the two groups are statistically representative of the population. Then, we have to make sure that all other “non-treatment” factors are equivalent, including access to facilities, resources, etc. That is, anything that we don’t consider to be a feature of the treatment itself. This is a randomized, controlled trial.