A USA Today investigation found what appears to be compelling evidence of teacher cheating in Washington, D.C., schools that were heralded as major successes due to test score increases. The smoking gun: too many erasures resulting in answers being changed from wrong to right. The numbers are so extreme that they do seem to indicate that massive cheating occurred. Not surprisingly, the school district is none-too-eager to investigate — especially because teachers at the schools were given big bonuses as rewards for the test-score improvement. Though on Tuesday, acting D.C. schools chancellor Kaya Henderson did request a review.
When Brian Jacob and I investigated teacher cheating in Chicago schools, which we described in Freakonomics, we didn’t use erasure analysis. Rather, we developed new tools for identifying strings of unlikely answers.
You might ask why we didn’t use erasures, when it is such an obvious approach. The answer: unlike the D.C. schools, the Chicago schools did not farm out grading of the test exams to a third party. What got the D.C. schools in trouble is that the third party routinely analyzed erasure patterns. The internal group that scored the exams in Chicago did not routinely look for erasures; that was only done when there were suspicions about particular classrooms.
Conveniently, there was an acute shortage of storage space in the Chicago warehouse where the test forms were graded. This, of course, necessitated that all the actual test forms be destroyed and disposed of shortly after the test was administered.
Some teachers in D.C. are surely wishing there had been a similar lack of storage space in our nation’s capital.
(HT: David Clayton)