Charles Murray, one of the authors of The Bell Curve, had three articles on The Wall Street Journal online last week, dealing with IQ issues. I read The Bell Curve when it came out several years ago. At first I thought its arguments were fairly compelling, but when I reread them and compared them to my observations, I started seeing holes big enough to drive a truck through. There are a couple of interesting points in there, but there's a whole lot of dreck too.
I'll just mention one point here and probably have some more later. The book says that IQ is the best predictor of job performance, regardless of the job. Yes, on pages 78 and 79 of my hardback copy, the book says that even a busboy's job is done better by a busboy with a higher IQ. I've worked with people with IQs ranging from average to very high, and supervised a bunch of them over the years, and I draw a very different conclusion from my experiences. If I were hiring right now, and had access to the IQ scores of my candidates, (problematic here b/c I don't believe that IQ scores are always closely correlated to g due to text anxiety, etc.) and if I could pinpoint the minimal IQ that it would take to do the job, I might use those scores to identify a pool of candidates that I would be interested in. But for the next step, I would throw out the IQ scores and examine that pool of candidates for the important, make-or-break attributes: Can you show up for work every day? Get along with your coworkers? Take direction? Are you a team player? Do you shirk unpleasant tasks, or do you pull your weight? Are you curious enough to ask questions and learn more and more skills and help the group problem-solve, or do you just want to do your little tasks that you've picked out? Can you do things that seem stupid to you or that you don't understand the reason for, just because you're supposed to? (A big one in my field, always.) These things have little or nothing to do with IQ, and I say that because somehow the very smartest people I have worked with (smarter than me) have had their effectiveness in the workplace greatly diminished because of these. I've had to have two people I supervised fired over the years. (Only two, and that's probably because I'm too nice.) The second was a cut-and-dried case of falsifying, but the first was a person who was extremely bright, but who could not seem to exchange his internal requirements for external ones; that is, if a process struck him as being the right and appropriate thing to do, no one could convince him otherwise. You cannot have that in a regulated field like environmental chemistry. We couldn't get time considerations across to him either - like prioritizing work according to customer needs rather than what seemed to him the most elegant way. When he was let go, we replaced him with a woman who was much younger than he was, less experienced and less educated, and probably had less abstract intelligence, but she got in there and got the job done. Cared that it was done right, i.e., by the book, and on time. She was a much, much more valuable employee by anyone's measure. IQ by itself does nothing for the employer. I think having a high IQ is like having lots of money: you can spend it to do things that are fun and interesting, you can use it to benefit other people, or you can bury it in the back yard and forget you ever had it until it rots. Having it doesn't mean much, it's how it's focused and what you do with it.
And all of this seems pretty self-evident to me, which is one reason why I find The Bell Curve and the further writings of its surviving author so irritating.
OK, well, here's another one. Although the book is careful to point out that even if you know the average IQ of a particular population, you can't apply that to a specific member of the population, people do that anyway. So the book goes on and on about demographics and the reader is strongly tempted to think of people as members of a demographic, not as individuals. Some time ago I had a conversation on a message board with a person who told me that because I am from Mississippi, I am less likely to be literate. I couldn't convince him that because he was dealing with an individual, "less likely" or "more likely" was irrelevant; either I was literate or I was not. He insisted that he liked knowing things like that before he dealt with people because it saved time. Another person in the discussion said that that was about the clearest exposition of racism he'd ever seen - only it wasn't racism, of course, it was regionalism (I guess). Same concept. I think the demographic stuff could be of very limited use. For instance, if somehow you could know the average IQ score of the students in a particular school (and see my caveat above about that) you could predict the average scores of various standardized tests and compare your predictions to the actual scores to see if the school is doing an adequate job of educating that population. You would not know how the school is serving the kids at either end of the IQ range. You would certainly not know the capability of any particular child at that school. Unfortunately I think a lot of people do that "time saving" thing without even realizing it, and what a pernicious thing that is.