Yesterday, the US Department of Education released a data table of state high school graduation rates, thus undoubtedly prompting every state governor’s office to go into damage control or celebration mode. My guess is only the top 10 states had the latter option, but I digress.
Texas’ Governor Perry wasted no time in getting the word out about the state’s 86% rate:
Proud to see TX ranked 3rd highest in HS grad rates, our hard work is paying off & students reaping the benefits! cc: @michaelwilliams
— Rick Perry (@GovernorPerry) November 27, 2012
Given Texas’ notorious historical high school dropout problem, I rushed to Google News to see if this were actually true. It was there I saw 3 separate Texas news sources – 2 from Austin, 1 from Dallas – reporting 2 different rankings for the state:
So which is it, folks? Is Texas ranked 3rd or 4th in the nation? Governor Perry’s office says 3rd, but we all know politicians prefer to pick the most favorable numbers, and Perry’s office might have just hit Google News as I did and picked the best one they saw.
I went back to the original story, and opened the original PDF in Adobe Acrobat directly from the URL (Thank you, Windows shell). Then I converted the PDF to an Excel Workbook via File -> Save As -> Spreadsheet -> Microsoft Excel Workbook. I opened the resulting file in Excel and, after deleting some extraneous cells, performed an expanded sort on the All Students column. As you can see in the file attached below, Governor Perry’s office – and The Republic – is correct: Texas’ high school graduation rate is indeed 3rd in the nation if you use dense ranking (my preferred methodology for anything). If you use standard competition ranking, the state ranks 4th.
As an engineer, I prefer dense ranking from a resource selection perspective. Standard competition ranking is misleading for that purpose because it implies in this case that there are 3 other distinct graduation rates above 86% when in fact there are only 2.
Before we all pop the champagne though, the Department of Education cautions:
The new, uniform rate calculation is not comparable in absolute terms to previously reported rates. Therefore, while 26 states reported lower graduation rates and 24 states reported unchanged or increased rates under the new metric, these changes should not be viewed as measures of progress but rather as a more accurate snapshot.