For Immediate Release: Wednesday, June 16th, 2010
Contact: Karen Conner or Eve Turow, news@epi.org 202-775-8810

Lawrence Mishel, President of the Economic Policy Institute and head of its education research program, today called into question the accuracy of “Diplomas Count 2010: Graduation by the Numbers – Putting Data to Work for Student Success,” Education Week’s report on the nation’s high school graduation rate.  Below please find the letter to the editor that Mishel sent to Education Week and the statement he issued with James J. Heckman, Paul A. LaFontaine and Joydeep Roy in 2008, when the writers of the Education Week report used the same methodology that they used this year.

To the editor:

While Education Week’s effort to track the U.S. high school graduation rate is laudable, the authors of “Diplomas Count 2010” continue to understate the number of students who graduate from high school each year—particularly the number of minority students.  In 2008, I partnered with economist and Nobel Prize winner James J. Heckman and two other experts on high school graduation rates, Paul A. LaFontaine and Joydeep Roy, to issue a statement that called the Diploma Counts graduation rate estimates “exceedingly inaccurate” and that highlighted the flaws in the report’s methodology.  Two years later, Education Week is still using the same methodology, which doesn’t fully take into account students who repeat grades and therefore overstates the high school dropout rate.  I strongly encourage the authors of this year’s study to revise its methodology for future studies.  High school graduation rates provide us with critical information about the state of American education, but this information is useless if we can’t count on its accuracy.

Sincerely,
Lawrence Mishel
President of Economic Policy Institute

In our examination of the data and methodologies available to estimate high school graduation rates we have found that insights can be gained from household surveys and from administrative data on student enrollment and diplomas granted. However, we find the measures of graduation rates in Education Week’s Diploma Counts project, computed from diploma and enrollment data, to be exceedingly inaccurate. The main problem is the assumption that the number of students enrolled in 9th grade is the same as the number of students entering high school. This assumption artificially lowers the estimates of current graduation rates, especially for minorities who are more likely to be retained (repeat 9th grade). This measure also artificially reduces the growth of the graduation rate over time because the practice of grade retention has grown over time, again, especially among minorities. The resulting errors are sufficiently large to artificially lower the graduation rate by 9 percentage points overall and by 14 percentage points for minorities. Grade retention also differs sharply across states and localities, distorting geographic comparisons. Last, these measures do not reflect the ultimate graduation rates of a cohort of students because the data do not capture diplomas provided by adult education and other sources than schools.