After flipping through Malcolm Gladwell’s Outliers: The Story of Success late last year, I have finally read the book (nothing like over 30 hours of travel to get through a few).

Having heard a few podcasts involving Gladwell (such as this), I knew largely what to expect. Gladwell is strongly on the nurture side of the nature-nurture debate and is dismissive of explanations involving the individual or their inherent traits. While he does (at times) concede that nature might play a role, he suggests this is uninteresting and that we pull this explanation out too often. I think he is right that it may be pulled out too often in explaining the success of a particular person, but there is a large gap between giving nature the right level of focus and ignoring it altogether as Gladwell suggests.

So, rather than reviewing the book (as has been done plenty of times in the blogosphere already), there are a few specific parts of the book that I feel are worth mentioning.

First, the main points of agreement. I don’t doubt that for the most extreme of outliers - take Bill Gates or the Beatles - that luck played a large part. If Bill Gates had been born in any other country or if computers were not available to him at school, he would not have founded Microsoft and become the richest man in the world. Similarly, I don’t doubt that an ice hockey player is more likely to become a star if they have the good fortune to be born at the right time of the year. Nassim Taleb makes many similar points in The Black Swan on the role of luck.

The other side of this point, however, is that there is still plenty of room for nature to play a part. Why did Bill Gates and Paul Allen, of all the students at their school, take advantage of this opportunity? The January born ice hockey stars are still a very small sample of those born in January, so what distinguishes those January born stars from the others born in January? And the December born players who make it despite their disadvantage?

In some ways, Gladwell’s focus on the most extreme of outliers for much of the book is what gives luck such an important role. Take the example he makes of the little benefit to having an IQ above 120. Even if that were true (I am not sure it is - in many sciences those extra IQ points are still worth a bit), 90 per cent of the population has an IQ below 120. IQ is a strong predictor of income, status, health and a raft of other factors. While someone with an IQ of 140 might be as likely as someone with an IQ of 180 to win a Nobel prize, Nobel prizes are not the measure of success for most of us. If Gladwell had been examining success in the way most of us think of (or experience) it, IQ and other inherent abilities cannot be ignored. Or to put it another way, the absence of difference in outcomes between someone at the 99.9th percentile and 99.99th percentile of IQ does not mean it is unimportant for everyone else.

This brings me to Gladwell’s strong focus on IQ, as opposed to other heritable characteristics. In Gladwell’s discussion on the link between hard work and maths results, he refers to the Trends in International Mathematics and Science Study (TIMSS) test. It was found that the ranking of countries in this test corresponded to the country ranking for the number of questions answered in the accompanying (and 120 question long) questionnaire. Children who did better at the maths test also filled out more information on their family, education and a raft of other background issues. Gladwell points to this as evidence of the link between hard work and mathematical achievement, as it takes patience to work hard and learn mathematics or to answer the questions. He suggests that any IQ (or inherent quality) based explanation is flawed.

Ignoring that the ability to fill out a long questionnaire at a young age is probably influenced by IQ (answering questions on family education requires some cognitive skills), Gladwell lines up his attack on IQ but does not question whether a broader suite of heritable traits might be at play. If it is not IQ that is relevant, Gladwell suggests it must be environmental factors. Take time preference (patience), which has a heritable component and would undoubtedly influence competency at mathematics and willingness to complete the survey. Might that play a role? Gladwell draws a similar conclusion on the lack of success of Christopher Langan (with an IQ approaching 200) and suggests that compared to Robert Oppenheimer, he lacked the skills required to navigate the world. Once he claims to have eliminated IQ, Gladwell pins it to environmental causes, despite the possibility that these other skills have a genetic component. (Gladwell’s approach reminded me of a paper by Samuel Bowles and Herbert Gintis on the inheritance of inequality. The attempt to pin down the heritability of the level of income to IQ showed that other genetic factors would need to be considered. I’ll blog about this paper in the next couple of days.)

Two other anecdotes stuck out. First was Gladwell’s example of Jewish immigrants coming into New York with a wealth of tailoring skills at just the right time. He suggests that their children went on to become highly successful (usually as lawyers and doctors) after they saw the hard work of their parents in the home - hard work that those parents “lucked into” by having a skill that was suddenly in huge demand. It is a nice story, but it does not explain the success of Jewish immigrants in field after field where high cognitive ability is an advantage - be that banking, law, research (plenty of Nobel prizes there), medicine, and the list goes on. The success occurred on such a broad scale despite the varied (and often disadvantaged) family histories. Should Gladwell be looking further back in time for an explanation?

He does that in the other anecdote I found most interesting, which was Gladwell’s discussion of some intractable family disputes in some parts of the United States (think the Hatfields and McCoys). Gladwell suggests that their ancestors originally came from marginally fertile areas where herding dominated and there was a need to establish a strong reputation to protect their herds. This resulted in “cultures of honour” forming, in which misdeeds needed to be punished quickly and brutally to ward off future attacks. When they migrated to the United States, Gladwell suggested that these people brought their culture with them and it has persisted through generations, despite the shift in countries and for many people, significant changes in wealth and status. It is an interesting explanation, but it is one part of the book where innate traits are crying out to be examined. Gladwell did refer to some interesting studies on this issue, which is something that I will definitely be following up.