Thanks to the many readers who sent in this tip.
The Iowahawk, a.k.a. David Burge, the beloved assassin of pomposity and pretension has taken the often hysterical Paul “Global Warming Skeptics are Traitors” Krugman to task over education statistics.
It seems Krugman has taken the sides of the cowardly politicians (all Democrats1) in Wisconsin. You know, the ones who scurried away to Illinois (!) when they realized they would lose a vote. We musn’t be too harsh on these politicians, for their actions were instinctual, motivated by the same survival impulse that drives cockroaches to sprint for cover when the light comes on.
Incidentally, just like those nasty bugs, self-serving politicians cannot be eradicated by force. Poison is useless. Stomp on one and two more instantly appear. The only solution is to cut off their food supply: do not vote for them.
Anyway, Krugman, using sources known only to himself, “proved” that education outcomes were better in unionized Wisconsin then they were in non-unionized Texas. Thus, we should acceded to the demands of the Wisconsin activists who dictate that more money should be taken from the working people of that State and given to them.
The only thing Krugman did right was to take on a worthy target. Too bad everything he said was false or misleading. Burge found a hilarious admission from the Times’s ombudsman Daniel Okrent (click and read all Okrent has to say):
Op-Ed columnist Paul Krugman has the disturbing habit of shaping, slicing and selectively citing numbers in a fashion that pleases his acolytes but leaves him open to substantive assaults.
Not a bad euphemism for lying, that. One wonders how the lacrymose Krugman (“O! The planet!”) responded to his colleague’s disapprobation. Okrent says, “I didn’t give Krugman…the chance to respond before writing the last two paragraphs. I decided to impersonate an opinion columnist.”
In his first post, Iowhawk did what should be done: he found the raw, relevant numbers that best compared educational success for Texas and Wisconsin. The most obvious bit of detective work—well, obvious to Burge but not to Krugman—was to recognize that the racial makeup of the two states was different. Whites, Blacks, and Hispanics do not live in anywhere near the same proportion in these states, and neither do these two groups score the same on standardized tests.
There are many more Whites in Wisconsin and Whites tend to score better on standardized tests than do members of the other groups. Thus, raw comparisons between the states will tend to show Wisconsin out front, which is misleading—a fancy word to say wrong. It was these wrong numbers Krugman used.
But if we use the proper numbers, broken down by race, as Burge did, we find that in each year, in nearly all subjects, in nearly every pertinent measure, Texas trumps Wisconsin. Using Krugman’s logic, we should thus fire every union teacher in Wisconsin and hire a non-union ones in their place.
Wait a second! How can Wisconsin do better overall yet Texas win in every subcategory? Isn’t the overall measure just a sum of the subcategories? Texas should be the winner overall, shouldn’t it?
It was in his follow-up post that Burge made us most proud, offering an excellent definition of Simpson’s Paradox, and showing how that manifested itself in the education statistics. Simpson’s Paradox is often found in disparity or inequality studies. Indeed, it is found so often that it is practically criminal not to check for it. It is not just criminal, but is nigh treasonous. And that means Krugman is a traitor! A traitor, do you hear me! Ach! Sputter! Arr…..
Whew. Sorry about that. I don’t know what came over me. My only excuse is to say that I spent too much time reading the New York Times today.
Back to the point: Simpson’s Paradox is found when subcategories of different proportions are summed (read the material on the link for a full explanation). Since the racial makeup of the two states are so different, Simpson’s Paradox is guaranteed.
Burge also tells us the difference between the ACT and SAT, why that difference matters, and why simple state-to-state comparisons of these tests are difficult.
The only point at which Burge and I differ is his use of the term “statistical significance.” I say that it is evil, misleading, and just plain wrong to ever use. However, I thank Burge for using it, because it provides me the perfect segue for tomorrow’s column. Don’t miss it!
Update1I do not mean to imply that no or few Republican politicians behave like cockroaches; clearly, many do. I do mean to say that the actions of the Wisconsin and Indiana Democrat politicians is cowardly and bug-like. Their behavior not akin to an outnumbered army wisely retreating so that they may fight again another day, for these politicians have already been vanquished and they know it. They are instead acting petulantly, like sore losers, cry babies, cockroaches. I meant only to speak of politicians and not citizens, and therefore apologize if any thought I was talking about them (unless you are a politician stealing towels from an Illinois Red Roof Inn, then I did mean you).