The Education Reporter's Dilemma
I’ve written so many posts about the misinterpretation of testing data in news stories that I’m starting to annoy myself. For example, I’ve shown that year-to-year changes in testing results might be attributable to the fact that, each year, a different set of students takes the test. I’ve discussed the fact that proficiency rates are not test scores – they only tell you the proportion of students above a given line – and that the rates and actual scores can move in opposite directions (see this simple illustration). And I’ve pleaded with journalists, most of whom I like and respect, to write with care about these issues (and, I should note, many of them do so).
Yet here I am, back on my soapbox again. This time the culprit is the recent release of SAT testing data, generating dozens of error-plagued stories from newspapers and organizations. Like virtually all public testing data, the SAT results are cross-sectional – each year, the test is taken by a different group of students. This means that demographic changes in the sample of test takers influence the results. This problem is even more acute in the case of the SAT, since it is voluntary. Despite the best efforts of the College Board (see their press release), a slew of stories improperly equated the decline in average SAT scores since the previous year with an overall decline in student performance – a confirmation of educational malaise (in fairness, there were many exceptions).
I’ve come to think that there’s a fundamental problem here: When you interpret testing data properly, you don’t have much of a story.