Cosma Shalizi is a rather egotistical-sounding young man of apparently Afghan ancestry. He is also an assistant professor in the Department of Statistics at Carnegie Mellon University in Pittsburgh. On his blog, Three Toed Sloth, he has a long post demonstrating that a popular form of mathematical analysis generically called factor analysis cannot be used to demonstrate the existence of IQ (or 'g' as we psychometricans call it).
His criticisms are perfectly correct. Factor analysis cannot prove ANYTHING in fact. It is just a convenient but rather arbitrary way of summarizing a set of correlations. Factor analysis is such a weak technique that I myself in my more than 200 published academic papers have used it only rarely -- even though I normally present my research results in correlational form. Shalizi is also correct in saying that much of the research into IQ has used factor analysis as a way of summarizing findings. That the findings are not DEPENDANT on that descriptive technique is the point he appears to overlook.
The underlying finding for 100 years or more is that ability to solve one sort of puzzle generalizes strongly to the ability to solve other quite different sorts of puzzle. Problem solving ability is general, no matter how you choose to summarize that. And problem-solving ability is what IQ or 'g' measures.
OK. What I have just said above is an excerpt from what I said on October 25. I emailed Shalizi a link to the October 25 post and I hear that others did so too. He has completely ignored it. In fact he has a very inflated recent post here in which he uses his previously demonstrated "wisdom" to attack the article on IQ in Slate by Saletan. Shalizi is so sure of his wisdom that he can only ascribe discreditable motives to Saletan and his editors for publishing what they did. And other bloggers (e.g. here) have taken Shalizi and his conclusions at face value. They seem to think that Shalizi has made lots of large correlations between different types of ability tests suddenly disappear!
A matter I did not address in my previous post is heritability. Once again in this case, Shalizi uses perfectly legitimate concerns about the statistical techniques used in summarizing the findings to claim that no firm conclusions at all are possible. In so doing he is using an old Leftist dodge that I commented on many years ago. He sets the standard so high for what he will accept as satisfactory evidence that nobody could prove anything to him under such standards.
In most of science, maybe ALL of science, you cannot prove things beyond all shadow of doubt -- so someone who does not want to believe something will always be able to say that the evidence is still not good enough. But if we normally behaved that way we would disregard most science. But we don't. And that is because we get a lot further by accepting that science is an enterprise that deals in probabilities rather than in certainties. If you want certainty, you need to turn to either theology or mathematics and you might not even find it there.
So what Shalizi is doing is what is called "intellectual dishonesty" -- judging a matter not on the balance of the evidence for and against it but rather on whether or not the concusions suit him.
And again, when you look at the underlying evidence about heritability that the various statistical techniques try to summarize, there is a lot there that Shalizi just cannot make go away. The IQ scores of identical twins will almost always be strikingly similar, for instance -- much more similar than the IQs of normal brothers and sisters or even of fraternal twins -- and certainly much more similar than the scores of random strangers. The facts on the ground just don't go away, no matter how you choose to summarize them. And those facts show that IQ scores are clearly tied to your genetic inheritance.
Razib makes further points about Shalizi's shilly shallying. Razib shows that, if you look hard enough, Shalizi does in fact to a degree acknowledge the underlying realities in his writings. But you would never guess that from his dismissive conclusions.
*************************
ELSEWHERE
Iraq involvement ending: "With the eyes of the world focused on the Middle East peace talks in Annapolis, Md., President Bush's war tsar, Lieutenant General Douglas Lute, quietly announced that the American and Iraqi governments will start talks early next year to bring about an end to the allied occupation by the close of Mr. Bush's presidency. The negotiations will bring to a formal conclusion the U.N. Chapter 7 Security Council involvement in the occupation and administration of Iraq, and are expected to reduce the number of American troops to about 50,000 troops permanently stationed there but largely confined to barracks, from the current 164,000 forces on active duty. "The basic message here should be clear. Iraq is increasingly able to stand on its own. That's very good news. But it won't have to stand alone," General Lute yesterday told reporters in the White House."
More rocket attacks on Israel during Annapolis peace conference: "With the opening of the Annapolis Conference, Palestinian organizations in the Gaza Strip are sending a clear message to those gathering in Maryland. Tuesday morning the Popular Resistance Committees announced the beginning of operation "Autumn Storm" in which the organization plans to launch rocket attacks at Sderot and the western Negev during the conference. Meanwhile, fighting in the field has not ceased for a moment: in the last 24 hours at least eight Palestinians have died in a string of clashes with the IDF, including attempts to launch rockets and plant bombs near the border."
Muslim riots in Paris worsen: "French police beefed up security yesterday after riots continued for a second night in flashpoint Paris suburbs despite the launch of a judicial probe into the deaths of two teens, which sparked the violence. Police said yesterday 64 officers were injured in clashes with youths in and around the suburb of Villiers-le-Bel, adding that five were in critical condition. "One policeman was wounded in the shoulder after being hit by a high-calibre bullet," a security official said. The injuries followed rioting in Villiers-le-Bel and the nearby towns of Sarcelles and Garges-les-Gonesses, police said. Riots intensified in the town and neighbouring areas, police said yesterday. Six hours of violent clashes erupted in Villiers-le-Bel on Sunday after the teenagers' motorbike crashed into a police car. Yesterday, about 100 youths crouching behind bins in Villiers-le-Bel hurled objects at 160 riot police, who responded with rubber bullets and teargas. Police said young rioters in other towns were armed with baseball bats, Molotov cocktails and bottles of acid."
For more postings from me, see TONGUE-TIED, EDUCATION WATCH INTERNATIONAL, GREENIE WATCH, POLITICAL CORRECTNESS WATCH, GUN WATCH, SOCIALIZED MEDICINE, FOOD & HEALTH SKEPTIC, AUSTRALIAN POLITICS, IMMIGRATION WATCH INTERNATIONAL and EYE ON BRITAIN.
List of backup or "mirror" sites here or here -- for readers in China or for everyone when blogspot is "down" or failing to update. Email me here (Hotmail address). My Home Pages are here or here or here
****************************
"Why should the German be interested in the liberation of the Jew, if the Jew is not interested in the liberation of the German?... We recognize in Judaism, therefore, a general anti-social element of the present time... In the final analysis, the emancipation of the Jews is the emancipation of mankind from Judaism.... Indeed, in North America, the practical domination of Judaism over the Christian world has achieved as its unambiguous and normal expression that the preaching of the Gospel itself and the Christian ministry have become articles of trade... Money is the jealous god of Israel, in face of which no other god may exist". Who said that? Hitler? No. It was Karl Marx. See also here and here and here.
The Big Lie of the late 20th century was that Nazism was Rightist. It was in fact typical of the Leftism of its day. It was only to the Right of Stalin's Communism. The very word "Nazi" is a German abbreviation for "National Socialist" (Nationalsozialistisch) and the full name of Hitler's political party (translated) was "The National Socialist German Workers' Party".
****************************
No comments:
Post a Comment