I previously posted my initial findings about the look of 1:1 in Iowa in January. This post should hopefully provide some additional insight. Like many studies, one of my first tasks was to identify controls and treatments. Identifying my treatment schools was fairly easy. I wanted to study 1:1 schools that had a 1:1 status prior to the current calendar year. After eliminating five of those schools for various reasons, I was left with 37 1:1 schools in my study. The next major challenge was identifying control schools for the study. Because I believed 1:1 schools in Iowa may look different than other schools, I wanted to identify control schools that were similar to the treatment schools. In order to identify those schools, I used propensity score matching. A simple definition of propensity score matching is that it is a technique to compare apples to apples.
This leads to some of the interesting findings from the first part of my study. I looked at nearly 150 school level characteristics comparing 1:1 schools to the rest of the schools in the state. Those school characteristics served as variables throughout my study. Eventually, I ended up eliminating many of those variables because they reported the same thing. For example, I had numerous different variables that all basically reported major discipline occurrences or teacher pay. Eventually I reduced the number of school level variables to 22. Of those variables, there were 11 that were very different between 1:1 schools and the rest of the schools in the state. Those variables and the means for each group are listed on the table below. It is a bit confusing, but important to note that these data are from 2007-08. It would have been improper to use current data because that data may have been impacted by a schools transition to 1:1. In other words, these data aren’t results of a 1:1 program. They instead attempt to capture the types of schools that have made the transition to 1:1 in the state of Iowa.