Thanks for continuing to shine a light on the misuse of statistics, and value-added analysis. As Mark Twain’s famous quote*, “Lies–damned lies–and statistics,” reveals, numbers are easily manipulated to convey truth or a highly nuanced meaning, when in fact, their value is highly dependent upon the logic used to produce them. The methods that produce quantifiable data are assumed valid on their face simply since data allow easy comparisons. It reduces the complex to the facile, allowing anyone with an opinion to rail against the object quantified, irrespective of the validity of the measure, or model, and hence, the data. “If the LA Times reports this, and it is data, surely it must be correct,” they think.
Sadly, right is not might in our world very often. Those with access to nearly limitless amounts of capital, and lest we forget – axes to grind, persist in perpetuating falsehoods like the LA Times value-added analysis of LAUSD teachers. While value-added offers some value as a management tool, its misuse at the individual teacher level is not clear to the average person. So, like the days of old, good citizens rally around the town square, pitchforks and torches in hand, ready to rid the castle of the purported evildoers who, when viewed properly, are simply those trying to do what the townsfolk want and could not do themselves.* Twain quoting Benjamin Disraeli in his autobiography. According to Stephen Goranson at http://is.gd/iejZcD, “Twain’s Autobiography attribution of a remark about lies and statistics to Disraeli is generally not accepted. Evidence is now available to conclude that the phrase originally appeared in 1895 in an article by Leonard H. Courtney.”