Friday, June 20, 2008

Diplomas Count, Part IV: How Do You Tell the Truth and Lie at the Same Time?

You use statistics, of course!

(Part of a series looking at the 2008 Diplomas Count report from Education Week; you can find other articles here)

Towards the end of the issue they touch on the April pronouncement from Margaret Spellings that she’d like to see states adopt a uniform standard for measuring graduation rates, as opposed to the 50 different formulas that are used now. An interesting argument for this is a chart comparing the state-reported graduation rate to the graduation rate that Education Week (or EPE, for Editorial Projects in Education) uses for their figures.

The differences are pretty astounding. New Mexico is the worst of the bunch, reporting a statewide graduation rate of 85.0% when EPE says it’s 54.1%, a 30.9% difference that equals thousands of kids. Mississippi, Delaware, and the Carolinas are all at a greater than 20% difference. Two states are within 5% of the EPE figures (Arizona and Utah), while Alaska actually reports a graduation rate lower than EPE’s number.

And Washington? A state reported 79.3%, EPE 68.8%, a 10.5% difference.

If it means anything. Eduwonkette makes a case on her website that the data model EPE uses is flawed, and that's certainly what New Mexico would say. When your reality is defined by how you count, the way you collect the numbers is critically important.

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