Since 1992, Sanders has written widely about his model but rarely in peer-reviewed journals where his calculations would be subject to professional scrutiny.
Educators and legislators are finally starting to ask questions, particularly since the stakes have been raised with student and teacher well-being made dependent upon secret calculations. Today's piece at Valerie Strauss's page is a good example.
Even the mainstream press is starting to print the views of those outside the oligarchs workshops. A clip from Sunday's Plain Dealer:
. . . .Value-added has been widely criticized because SAS Inc., the outside company that Ohio pays to calculate it, keeps part of the calculation process a secret. Since the company refuses to disclose it, many educators refer to it as a "black box."
Kenston's Lee said it reminds him of the Wizard of Oz working his magic behind a curtain.
"The data goes behind the curtain with the wizard," he said. "Then the wizard comes out and says who made it and who didn't."
But John White, a senior manager for value-added at SAS, said the company's formulas are all published and available on the Ohio Department of Education website and can be replicated by anyone with the expertise to do it.
Pioneered by William Sanders, a former University of Tennessee professor now working for SAS, value-added is part of a nationwide shift over the last 10 years toward measuring not just on whether students pass or fail a test, but how much they have learned or improved over time.
It is gaining in popularity nationwide. SAS also calculates value-added scores for every public school in North Carolina, Pennsylvania and Tennessee, as well as for individual districts in 13 other states.. . .