Income inequality and educational outcomes3 August, 2016 at 16:12 | Posted in Education & School | Leave a comment
A new paper by economists Katherine Michelmore of Syracuse University and Susan Dynarski of the University of Michigan … use administrative data from the state of Michigan to look at how economic disadvantages affect standardized test scores. Many studies on this question will look at the achievement gap during a single year and use a measure of disadvantage such as being eligible for subsidized school lunches. But the administrative data Michelmore and Dynarski use lets them track students over time to discern how often students were eligible for school lunches mapped to their test scores.
What they find is that there’s a difference—a significant one—in test scores in the 8th grade between students who are occasionally eligible for subsidized lunches and those who have been eligible every single year since kindergarten. The two economists consider students who have been eligible every year (14 percent of Michigan students) to be persistently disadvantaged. And they find that these students score a full standard deviation below kids who have never been on subsidized lunches (40 percent of students) and just under a quarter below students who are occasionally eligible for subsidized lunches (roughly 45 percent of students). (A standard deviation being further away from something than a quarter standard deviation.)
Why is there such a difference between students who are occasionally eligible for subsidized lunches and those who are persistently eligible? One possibility is that exposure year after year to low-income living adds up over time, pushing down test scores in the process. But Michelmore and Dynarski find that the vast majority of the gap between persistently eligible students is present early on in their schooling—3rd grade, to be precise—so the differences in exposure alone can’t explain the gap. Instead, the two researchers argue that the difference between persistently-eligible students and occasionally-eligible students is a sign that the former are from much lower-income backgrounds. It’s a story of income inequality, not income volatility.