In the wake of his recent paper on the stagnating high school dropout rate, where the gaps between the races have barely budged since the early 1970s, Nobel Laureate economist and master statistician James Heckman is back with perhaps an even more important study. This one tries to get economists to pay attention to "The Economics and Psychology of Personality Traits" (It's co-written with Borghans, Duckworth, and ter Weel.)
There is ample evidence from economics and psychology that cognitive ability is a powerful predictor of economic and social outcomes. It is intuitively obvious that cognition is essential in processing information, learning, and in decision making. It is also intuitively obvious that other traits besides raw problem-solving ability matter for success in life. ...
The power of traits other than cognitive ability for success in life is vividly demonstrated by the Perry Preschool study. This experimental intervention enriched the early family environments of disadvantaged children with subnormal intelligence quotients (IQs). Both treatments and controls were followed into their 40s. As demonstrated in Figure 1, by age ten, treatment group mean IQs were the same as control group mean IQs. Yet on a variety of measures of socioeconomic achievement, over their life cycles, the treatment group was far more successful than the control group. Something besides IQ was changed by the intervention. Heckman et al. (2007) show that it is the personality and motivation of the participants. This paper examines the relevance of personality to economics and the relevance of economics to personality psychology. ...
Our focus is pragmatic. Personality psychologists have developed measurement systems for personality traits which economists have begun to use. Most prominent is the “Big Five” personality inventory. There is value in understanding this system and related systems before tackling the deeper question of the origins of the traits that are measured by them. The lack of familiarity of economists with these personality measures is one reason for their omission from most economic studies. ...
Most economists are unaware of the evidence that certain personality traits are more malleable than cognitive ability over the life cycle and are more sensitive to investment by parents and to other sources of environmental influences at later ages than are cognitive traits. Social policy designed to remediate deficits in achievement can be effective by operating outside of purely cognitive channels. ...
We summarize evidence that both cognitive ability and personality traits predict important outcomes, including schooling, wages, crime, teenage pregnancy, and longevity. For many outcomes, certain personality traits (that is, traits associated with Big Five Conscientiousness and Emotional Stability) are more predictive than others (that is, traits associated with Agreeableness, Openness to Experience, and Extraversion). Tasks in social and economic life vary in terms of the weight placed on the cognitive and personality traits required to predict outcomes. The relative importance of a trait varies by the task studied. Cognitive traits are predictive of performance in a greater variety of tasks. Personality traits are important in explaining performance in specific tasks, although different personality traits are predictive in different tasks. ... [Via Arnold Kling.]
I suspect some of the evolution of Heckman's line of thinking in this regard goes back to his widely cited angry 1995 review of The Bell Curve in Reason entitled "Cracked Bell." This strikes many people who read it only once as a definitive debunking of Herrnstein and Murray. After all, here is this very, very smart statistician and, while it's hard to figure out exactly what he's so upset with the book about, he's clearly upset.
What people didn't realize -- and I think it's reasonable to bring this up now that the topic is personality -- is that Heckman is almost always upset. That's his personality. In a Medieval Big Four Humours model, he'd be The Man of Choler.
Years ago, I was participating in an email discussion with Heckman, who made all of his contributions to the conversation IN ALL CAPS.
As I recall, I privately emailed him to suggest -- diplomatically, I hoped -- that if he didn't find the shift key convenient, he could just eschew upper case altogether and type using only lower case, like e.e. cummings. You see, I explained, using all caps gives other readers the impression that you are shouting.
"I AM SHOUTING!" he emailed back.
Heckman's distinctive personality is one of the things that helps make him a great scientist. Heckman didn't want to silence Murray, like 99% of the critics of The Bell Curve did; he wanted to PROVE HIM WRONG. And that's how science progresses. (Of course, personality is a very tricky thing -- the other critic of The Bell Curve who has contributed much to our understanding of human nature, James Flynn, is genial and suave.)
Over the years, Heckman has made some progress toward that goal, but perhaps less than he had originally expected he would when he first attacked the book. That The Bell Curve has held up well is why it's so much more taboo now than it was 14 years ago (as the James Watson brouhaha showed).
So, perhaps Heckman has been trying to outflank Murray by admitting that while there isn't all that much the government can do to boost the intelligence of low IQ individuals, we can and should inculcate better character in young people. The funny thing is that the judicious and philosophical Murray would have told Heckman exactly that back in 1995, and probably illustrated it with a quote from Aristotle ... if Heckman had asked him and listened to him.
But what would have been the fun of that? A lot of old things you just have to figure out for yourself -- and in the process you discover a lot of new things as well.
By the way, back in December, I took a casual swipe at the IQ vs. character issue in my IQ FAQ:
Q. Isn't character more important than intelligence?
A. I believe so. Work ethic, honesty, conscientiousness, kindness, together they're more important than intelligence. (Of course, when it comes to making money, less endearing personality traits like aggressiveness also play a big role, but we'll leave that aside for now.)
Can I quantify that? Well, that's where things get tricky…
Q. So why not test for work ethic and the like instead of IQ?
A. We do test for it, in many different ways. Consider the process of applying to college. The two most important elements in the application are high school GPA and the SAT or ACT score. The SAT and ACT are more or less an IQ test, while high school GPA is driven by a combination of IQ and work ethic.
But demonstrating work ethic via GPA is a time-consuming prospect for the applicant … and even for the admissions committee. ...
Q. Couldn't somebody invent paper and pencil tests to measure character?
A. They have. They're pretty accurate … overall.
On the other hand, these tests haven't been all that popular, perhaps because they are liable to occasional catastrophic failures. The danger is that somebody with a high IQ but poor character would use his smarts to figure out what answers on the test would make him sound like the second coming of George Washington. And a high-IQ scoundrel is the last person you want to select.
You could call it the Ahmad Chalabi Problem. The Iraqi convicted embezzler with a Ph.D. in math from the U. of Chicago used his enormous brainpower to figure out how to dupe the neocons into believing that he literally was the George Washington of Iraq, so America should invade his homeland to make him president.
In contrast to character tests, the good news about IQ tests is that they are un-outsmartable. If you can use your brain to figure out what answers the test makers want, well, then you have a high IQ.