The New York Times published a tribute by Kevin Carey of the New America Foundationto William Sanders, “the little-known statistician who taught us to measure teachers.”
One hates to speak ill of the dead, but accuracy requires that we note that Sanders’ statistical model for “measuring” teachers was flawed, inaccurate, and damaged the lives of thousands of teachers based on Sanders’ obscure algorithms. Sanders was an agricultural statistician before he found a goldmine in education. Measuring teacher quality really is not akin to measuring cattle or crops. Every analysis of the influences on students’ test performance gives far more weight to family income and education than to the teachers who see her or him for an hour or five hours a day. Sanders tried to remove human judgment from the equation and ended up creating a profitable business that distorted teaching and learning into a struggle for higher test scores. If the tests themselves are invalid, then any accountability measures based on them will be invalid.
No one knows William Sanders’ works and its flaws better than Audrey Amrein-Beardsley. She has studied Sanders’ value-added measures for years and testified against them in court. She comments on the New York Times’ article here. Amrein-Beardsley points out that Sanders’ methods have been faring poorly in court because it is unfair to judge a teacher based on a mysterious algorithm that no one can understand or explain.
In my book Reign of Error, I wrote about the fallacy behind Sanders’ reasoning by quoting a song from “The Fantasticks.” I paid $1200 for the right to reprint the lyrics. It is the one that goes “Plant a radish, get a radish, not a sauerkraut./That’s why I love vegetables, they know what they’re about.”
No one can say the same about children. Children from the same parents are different, even when their upbringing is as identical as those parents can make it. They look different, they act different, they have different interests, they have different goals.
Sanders never understood that.
from sarah http://ift.tt/2q3AeAS