Despite the fact that major scholarly organizations have debunked value-added measurement as a way of identifying and quantifying teacher quality, there are still a few lonely defenders of VAM.

There is the U.S. Department of Education, which bet nearly $5 billion on VAM.

There is the Gates Foundation, which has bet hundreds of millions on VAM.

There are stragglers here and there.

And then there is the Center for American Progress, which says that despite all the research to the contrary, they are sticking with VAM.

Just a few weeks ago, the American Statistical Association stuck a pin in the VAM bubble.

The National Academy of Education and the American Educational Research Association had earlier expressed their skepticism about the utility of VAM.

Nonetheless, the CAP still wants to believe. They really truly want to believe, no matter what the statisticians and researchers say.

Probably they are just showing their loyalty to Arne Duncan and the Obama administration.

So Audrey Amrein-Beardsley decided to stick a pin in CAP’s ideological bubble. 

She writes:

Their research is notably a small subset of the actual research out there on VAMs, research that was used to rightfully construct the aforementioned position statement released by the ASA, and research that for decades has evidenced that teachers account for, or can be credited for, approximately 10% of the variance in student test scores, while the other 90% is typically due to factors outside of teachers’ control.

Regardless, while the Center for American Progress briefly acknowledges this, they spin this into their solution: The reason this percentage is so low is because we have not yet been accounting for growth in student achievement over time; that is, via value-added models (VAMs). In other words, using more sophisticated models of measurements (i.e., VAMs) will help to illuminate the “real” results we know are out there, but simply have not been able to capture given our archaic models of measurement and teacher accountability.

Not to worry, though, as they write that these “[n]ew measures of teacher effectiveness, determined by evidence of teacher practice and improvements in student achievement, are now available [emphasis added] and provide strong markers for assessing teaching quality and the equitable distribution of the most capable teachers.”

CAP wants to believe in VAM, therefore it does believe in VAM, no matter what the evidence may show.

This should be laughable but this skit, she says, is not funny.