Thursday 28 November 2013

IQ and Boris Johnson

It is unusual for a British politician to mention IQ. It is seen as a difficult subject, likely to draw criticism and lose votes. The basic rule is that you must flatter your audience. Phrases like “Of course, you-the-British-public are far too intelligent; far, far too intelligent to fall for the rubbish being offered to you by my opponent” are more suited to buttering up voters.

Giving the annual Margaret Thatcher lecture, the Mayor of London has drawn a distinction between the 16% of the population below IQ 85  and the 2% of the population above IQ 130. Apart from some inelegant phrasing, he was right to say that the former have more of an uphill struggle than the latter, who tend to get better jobs and earn more, often far more in a global economy. I have not been able to get the full speech, but just before the IQ comments he makes it clear that he saw intellectual worth as being different from spiritual worth.

So, cue outrage from many quarters. Not surprising, because the higher earnings of brighter people depend upon an open market economy, and that always has its detractors. More surprising was to be interviewed by The Guardian, which is usually a critic of IQ, but which faithfully reproduced the basic points I was making. Is this little blog beginning to get read, even among journalists? I hardly dare hope. As to the headline they used, I was criticising only the phrasing of the Mayor’s remarks, but not the reality of the findings to which he alluded.

Had I thought of it at the time, I would have asked the amiable journalists to read the following posts, which refer in part to the relationship between IQ and wealth.

Or you could just read Linda Gottfredson’s (1997) “Why g matters”

Can you pass on these links to a journalist you know?

London Slaves, and a Slavish Press?


Deep apologies, but I can’t keep away from the London Slaves story. It seems that because Austria had women hidden in basements by an incestuous and brutal father, and Cleveland had abducted women in a suburban house chained to the wall by a sexual sadist, London did not want to be left out, and was ready to believe any story about women slaves. The story as it came out had some very odd characteristics from the very beginning. The account was that the women had seen a charity spokesperson on TV and then phoned them up. There were “negotiations” and then the women walked out of the house. This immediately revealed that the women in question had been allowed to watch television, had access to a phone, and were able to choose a time to walk out of the house. Despite these discrepant facts, much of the Press, TV and Police followed the slavery version of events, hook, line and sinker. Even the Home Secretary, Theresa May, talked about “slavery being all around us”. Slaves, slaves, slaves, everywhere.

Prof Graham Scambler at UCL has been studying the sociology of London prostitutes. He has interviewed them, and followed a chain of recommendations such that these sex working women confided in him about their lives. In a nutshell, his view is that the number of London prostitutes who are “trafficked” is very small. The archetypal prostitute is a part-time worker building up capital, sometimes studying for a degree, with a fairly clear game plan and in control of what she is doing. There are a minority for whom the whole thing is an act of rebellion. He feels his work has had no impact on the general press narrative that sex workers are trafficked.

Although the BBC went along with the slaves account, within about a week other parts of the press soon dug up the real story. This whole farrago was a bust up in a former Maoist cult, which had attracted some gullible and troubled followers, some of whom stayed on to the bitter end. It appears that they had put their trust in a charismatic braggard who then manipulated and abused them. It appears to be so. The couple have not told their side of the story yet. Indeed, the women who fled the house haven’t been interviewed by the Police yet. They have been waiting for experts to pronounce as to when this can be done. As previously discussed, the story should have been kept in the can till the evidence had been collected. Currently, the press has identified everyone in this disturbed household, and even shown their photos, without pixilation this time. We have family backgrounds for most of them: a couple in the leadership role, a Malaysian woman, and Northern Ireland woman, and the daughter of a former disciple who fell out of a window and died in 1997. There is a story coming out every day.

It appears that the “London Slaves” story could have been characterised as: “Bust up in loony left cult”. I am a bit new to the task of creating headlines, but others are “Maoist cult in new schism” and “Communist Extremists destroy themselves”. My own version would be: “Some vulnerable children reject their families and their comfortable backgrounds and fall for a more rebellious father figure, probably because of personality frailties and adolescent fantasies and vulnerabilities which we don’t yet understand fully”. As you can see, headline writing is still a new skill for me.

How good is our understanding of cult membership? Rejecting one’s family is, in one sense, part of growing up in the West. Children leave home at 18 and do their own thing, sort of. That is, they establish their own sex lives, and drinking lives, and thinking lives, but come back for support, love, fragments of advice, and sometimes money. At times of crisis they rush back, recoup, and then get the hell out again. London has an additional element, in that high property prices mean that children often come back from college for the early years of their career, until they have sufficient income and savings to establish their own households. In other parts of the world, living with your family is what you do much of the time. Three generations may share a house in Far Eastern societies. Western ways are different, and thereby hangs a tale. Family structures are a little looser. Jobs are got on merit, not on clan. No-one has to exert themselves finding a job for a cousin. Western children have to make their own way, in competition with citizens from all over the world. It does not mean that there are no family connections, simply that there are fewer strings pulled, and they are furtive, not a cultural requirement. A child can flourish, and a few can perish.

Some researchers have put forward the view that anyone can enter a cult, because they join organisations which have features that attract them, and then the organisation takes them over. I have difficulty with that purely contextual explanation, because the attrition rate for cult members is very high. Most members leave, once they work out the organisers are scoundrels, and want them for their money, their labour, or for sex. Look at any account of cults and you find many who drift away, with no more attachment than one commonly gives to a fitness class. Something entrances those who stay: a challenge, a sense of belonging, a thorough rejection of their former live that goes deeper than we can easily understand. There could be a prior vulnerabilities of a psychiatric sort, but the picture is not clear. Most cult leaders are men, and domination of one sort or another is a common feature. You already know the pattern: the leader has a story which explains how the evil forces have done whatever they are supposed to have done to you, and so a defence has to be organised, a safe church established, a retreat from the corruption/cruelty/vacuity of society, and together with other new trusted friends you build a new and better society. Then it begins to go wrong, and a culprit is found, and they are ejected. Then disciples begin to inform on each other, and the whole enterprise turns sour.

Note that the account I have given could also have a good outcome. You might form a religious cult, head West, find a good place to farm, and live happily ever after, being pleased to have escaped from England. Some cults become denominations, some denominations become churches, some churches become nations.

Happy Thanksgiving.

Monday 25 November 2013

Thanks for your donations


Many thanks for your donations. I am going to make a start on the national IQ database, and also start working on a number of “frequently debated themes”, just to set out the current state of the argument. 

Perhaps I set the bar too high by mentioning that a pay-walled paper costs $35 and is often very boring. A book on intelligence can cost as much as $30, and only parts of it will be interesting. The Sunday Times costs £2.40 and is less boring, and also far less reliable. So, by my calculations the sweet spot between entertainment and quality is probably balances out at about $10. Two coffees and a cookie. And then you need something to read.

The Donate button is still just below this post, on the right.

Sunday 24 November 2013

Trauma and the Press

One of the problems of dealing with the aftermath of disasters is figuring out how to deal with the press. Handled properly, sympathetic journalists can provide sensitive descriptions of what it is like to be traumatised, and how to seek treatment. Handled badly, they can be a nuisance and get in the way of patient recovery.

As a relatively new clinic in 1987 with a de facto national referral status, we worked out a protocol. When the media rang up, breathlessly asking for a trauma patient to take part in a program, we put them through a standard process. They were asked to write to us saying what sort of program it was (documentary, studio discussion, extended interview) and telling us what other work they had done, to see if they were responsible journalists. Then we would present the most reasonable of those requests to therapists at the weekly ward round saying “Another media enquiry, which seems OK. If you have any patient you think might be interested, and who might benefit from it, the secretary has the details”. Some patients took up the option at the end of treatment, and sometimes found it very helpful. They “showed the world” what it was like to suffer extreme anxiety, and that they had got through it. Other patients, particularly those who were called to studio discussions and interviews sometimes got messed around. They would ready themselves for the interview, and then be told they had been dropped, thus implicitly being classified as not sufficiently newsworthy. Not a good experience. Most patients avoided such enquiries. They had seen the Great British Press in full ravening frenzy all too often.

As the years went by, and trauma reactions became much better understood, although we went through the motions of vetting journalists, making them explain themselves and being kept at a distance, we usually defaulted to saying “We don’t do that at our clinic”. When patients asked about how to reply to media enquiries we replied “Up to you, but why not wait till at least 3 months after the end of treatment?” Three months to a journalist is about three decades too long.

These reflections were engendered by the London Slaves story, about which I was promising to say nothing as long ago as yesterday. The charity who launched the story are now asking the press to respect the privacy of the women who have been released from the house where they lived with the couple they accuse of abusing them. The charity and the police are reminding the press that they may bring charges against the couple, who are currently on bail, so they cannot give explanatory details.

Then the Police started giving details, saying that the inhabitants of the house were probably originally members of a political group living in a commune, and that the couple had been interviewed decades before, for some undisclosed reason. The Police then crawled over a London street, interviewing the locals, thus confirming the location. Enterprising journalists have contacted neighbours (as predicted in this blog) and have found a man who claims to have been pursued by the youngest woman (now 30) over a seven year period, saying that on her frequent outings with the couple she posted 500 or so love letters to him through his letter box, including 7 photos, one of which the paper helpfully publishes, with some pixilation over the face, saying she was of Indian appearance, lest we not work out what sort of person the press desperately want to interview. Since the house in question seems of recent construction the press are asking the local authority what they knew about the inhabitants, and where they lived beforehand.

We now have two press campaign. One is about slavery; “tip of the iceberg” calculations about London sweatshops and slaves and national scandal and “modern slavery is all around us”; the intricacies of immigration law; and a Modern Slavery Bill which, curiously enough, the Government says it is just about to introduce in Parliament. The other campaign is to find three women who are living somewhere, trying to avoid the press. The leader of the charity, while requesting privacy for the women, has revealed their first requests on leaving the original house. It has all the appearance of a cynical mess.

Now, consider another scenario. You get an anguished telephone call for help from someone who appears to be held against their will in a house. It is a complicated situation, and they cannot give a clear account. They are frightened and want to leave, but cannot bring themselves to escape from psychological oppression and dependency. You manage to get them out, take them somewhere else, and slowly let them tell their story, while the Police investigate the accused couple, and see if they can bring a prosecution. Enquiries can be made in the street in question, and in other relevant places, under some cover story without arousing too much interest in this particular household. Armed with the story obtained over many months of patient interviewing, and with corroborative evidence from the Police investigation there is a court prosecution, the case is proved, and the oppressors go to jail. Later, if they want to, the three abused women tell their story, in the company of supportive helpers. I think that the second approach is the professional way to do things, and is most likely to obtain a successful prosecution. As it stands now, if the case gets to Court,this couple now have a sparkling defence: the whole country knows that they are slave masters, and a fair trial is not possible, etc.


By convention, as established in Hitchcock’s “Psycho”, the psychologist comes on last, after all the horror, to give the final convincing explanation as to why the ghastly events took place. So over two days I have been listening on the end of a phone as all other parties do their bit on the radio programs, until they finally come to me. So far I have sat patiently through many an impassioned declamation as to what needs to be done in legal, moral and international terms, but the prize goes to the speaker for the charity, who in one sentence about the women’s condition mentioned her charity at the beginning of the sentence, the middle of the sentence, and the end of the sentence. Apparently they are getting many, many calls, and may have to take on new staff.

Now we are One: Blog Birthday



As proof of my willingness to respect blogging convention, here are my reflections on the first anniversary of “Psychological Comments” started on 23 November 2012.

I begin with a confession. I had made a false start with 4 posts in November 2009 and several tweets which led to my getting 16 followers. Few people read the blog, and my tweets were not about the postings, but about concerts I had attended. The whole thing seemed absurd (particularly getting 16 followers for no reason) so I gave it all up.

The fresh start 3 years later was triggered by having paid to fly to the International Society for Intelligence Research conference in San Antonio in December 2012. I must have felt that I needed to justify the expenditure by blogging about the conference. I had great difficulty finding my old blog again, and in remembering the password, but I eventually began again with a criticism of a report on child sexual abuse (80), a review of a production of Euripides’ Trojan Women (128), a note on timepiece displays and astronomical time (79), social class and university entrance (130), intelligence and the credit crunch (107), fear of flying (68) and finally, conference news (20). That’s right, the final post, the supposed reason for re-starting my blog, got only 20 views. It was 4 sentences long. I was too involved with the papers and asking questions to be able to blog anything.

By January of this year I eventually commented on some of the conference papers, and got into the habit of producing copy. Not many people read the blog, but it didn’t seem to bother me too much. Since starting up again this January have done 189 posts, which is one every two days. I do not know why it became easy when it had seemed pointless previously. 395 people looked at “What makes a good IQ story?” which was pleasing, because my internal metric was a factoid that claimed that the modal published psychology paper readership was 6 people, and that included collaborators and family members.

One day, noticing a colleagues’ publication in the press, I sent him a preview of my comments, asking him to correct any errors. He replied that the story was great and that “I have re-tweeted it”. I went to UCL to have coffee with another friend, and earnestly asked him what re-tweeting was. So, my thanks to Prof Graham Scambler for the Twitter tutorial and to Prof Sir Simon Wessely for my first re-tweet.

Since then I have followed the procedure (virtually always) of sending the story to the principal author, asking for the correction of errors, requesting that they update me with their more recent publications, and encouraging them and their colleagues to reply to any of my criticisms. Any author who does so gets their reply posted without comment or quibble from me.

In early April I read that Prof David Colquhoun, FRS, had won a prize for his blog, so I wrote to him for advice. He told me his big break came when the Provost of UCL threw him off the UCL server, which made the news and drew in a lot of sympathetic traffic. Since I was already on an independent server, this martyrdom strategy was not open to me. He guided me to Prof Dorothy Bishop’s introduction to Twitter for academics, and gave me other sound advice, for which many thanks. He gets 1200 views every weekday “with a surge after I've posted something new.” You have to respect these established bloggers.

By late April I knew my place in the blogosphere. A popular post like “Flynn Effect raises all boats, but some are leaky” would get an astounding 452 views, admittedly over several days and weeks, but highly gratifying nonetheless. Others would get more modest readerships of 79.

In May, while on a holiday in France, I was electronically accosted by a young reader in America, letting me know that someone had lost his job because of saying in public what any academic already knew about Hispanic intelligence and scholastic achievement. So, sitting by the pool, I did my duty and pointed out that the research findings were on the side this person, and if anyone could prove him and me wrong, I would send them a bottle of fine French wine. “Jason Richwine and a bottle of Rich Wine” got 1539 views over a day and a half. So, I am sorry that Dr Richwine was treated in this ignorant and bullying fashion, and am grateful for the prompt to action from the outraged Elijah Armstrong.

At this stage things become hazier. Lots of colleagues gave me a helping hand, mostly without my knowing it. Steve Sailer, whom I had read for many years, gave me a mention or two in iSteve, thus enormously boosting my visibility. HBD chick always posted links to my work, as did JayMan and others. Many thanks to all of you. Unknown sites re-directed traffic, including newspaper discussion boards. I began to tweet selected phrases from each post, so as to encourage readers to investigate the story. Dr Michael Woodley and colleagues wrote a paper “Were the Victorians cleverer than us?” which got 428 views and lots of press coverage, the latter provoked by my one press release so far. Dr Stuart Ritchie let me know of relevant publications. Prof Ian Deary supplied publications and explanations. Prof Robert Plomin let me publish a paper he had sent to PLOS ONE which got 827 views. Charles Murray directed readers to my summary of Ian Deary’s primer on intelligence, which got 2,573 views.

On 2 November a 15 year old Californian who claims to type with his feet let me comment on his first published paper, written with Michael Woodley, quickly obtaining 3,393 views. Thanks again Elijah, and Michael.

Top Ten

Flynn effect as a retesting, rule-based gain

All you ever wanted to know about intelligence (bu...         2573

Helmuth Nyborg gets Watson’d                                            1889

Are girls too normal? Sex differences in intellige...               1680

Jason Richwine and a bottle of Rich Wine                           1539

Give me a child until he is seven, and I will give...               1059

ORIGINAL PAPER: "A response to Prof Rabbitt – The ...    791

Jason Richwine, and an unclaimed bottle of rich wi...          765

ORIGINAL PAPER: Strong genetic influence on a UK n...  710

Maths is a man thing*                                                             634

Reflections: There is only a weak correlation between what people find interesting and what I imagined they would find interesting; it is fascinating and encouraging that just after I have posted something, someone somewhere almost immediately reads it, thus providing an intrinsic reward not usual in academic publishing where there may be a year’s delay between writing a paper and seeing it published; countries rise and fall in readership for no discernable reason, though the US now clearly provides most of my readers; my commentators are polite, well-informed and evidence based, and provide encouragement while identifying anomalies, contradictions and relevant additional publications. In conclusion, I predict optimistically that bloggers and commentators will break the stranglehold of academic publishers and we will soon all become what we once were: a community of scholars.

Finally, I can claim that in one year 71,701 readers have given my words a look, as opposed to the modal 6 if I had published a paper. I even have a select 199 Twitter followers. I hope to continue blogging about intelligence and other matters, without fear or favour.  A very big thank you to all of you for reading my little blog. Thank you so much. It beats talking to one’s self.

On that note, my investment in free journalism has not gone un-noticed by my wife who now calls herself “The Blog Widow”. I would like to buy her some flowers for Christmas and also add features to my blog, such as more new figures showing data, and establishing a database of national IQ results. It would make my life easier if I was able to tell her that I was a working journalist. Can you please send me a donation? The cost of an academic paper behind a  Publisher’s paywall is $35, and that is just one unreadable paper, not 189 readable commentaries. There’s a Donate button just below, on the right.

Friday 22 November 2013

London slavery case: lack of facts no impediment

An account has been given, by a charity and by the Metropolitan Police, of three women who appear to have been held as slaves, in appalling conditions, for at least 30 years in a house in London.

The details are still sparse, since there are likely to be charges against the couple who lived in the house with the three women, and giving too many details could prejudice any prosecution. At the moment it is very difficult to work out what happened. There have been many news broadcasts, interviews with the charity, with government officials, and with spokesmen and campaigners of various sorts.

And there, of course, the story should end. We should wait however many months it takes for the women to tell their story, and then the couple to tell theirs, presumably as part of a prosecution case. At the moment it seems very hard to put forward an innocent explanation, but innocence is what the law must assume.

Naturally, the Press, on behalf of the public, want details and explanations, and very probably pictures of all concerned, plus the precise address of the house, and photos of the interiors, and interviews with neighbours, the latter asking why the did not notice anything.

In the meantime, one of the strands to the story is the psychological effect of such incarceration. The basic effects do not require a psychologist to spell out. However, there are some interesting and perhaps unexpected findings. If a child is abducted even as late as 9 or 10 years of age, then there is a chance that the child will later fail to contact or search for their family. This is usually after prolonged maltreatment and manipulation. After years of such influence, the victim may have access to a telephone, but never use it for the purposes of seeking out their parents. Other victims, usually older, preserve a strong sense of their former lives, and seek escape when it seems safe to do so. A previous post on the Natascha Kampusch case and one on the Cleveland case covers some, but only some, of these issues.

Many relationships have the potential for abuse: caring for children, the elderly, and those who are otherwise vulnerable because of low ability and fragile personalities. There is literature on undue influence, bullying, domestic violence, child abuse and other inhumanities. Some of the campaigners have been called for changes in legislation. That is understandable, but no legislation can bring relief unless there is reliable detection and implementation of laws. All that is tricky, given that people live in houses, and want private lives. So, in every urban street there will be a majority living ordinary and humane lives, a very few doing terrible things, and many wondering how we can tell the difference between the two, without damaging every household in the process.

Thursday 21 November 2013

Failure on diet IQ test


Full disclosure: after saying that diet was an IQ test, I failed the next item.

Mazi 12-14 Hillgate Street, London W8 7SR (tel 020 7229 3794) is a deconstruction of Greek restaurants, in that it aims to be innovative, tasty, and even refined. The decor is refreshingly sparse, no fake taverna kitsch, the table tops plain oak, menus in English, no bouzouki music, just conversation, which is entertaining enough because about a third of the customers are Greek.

Spicy Tiropita, broken filo pastry, leeks and chillies; Fish Roe Mousse Tarama; Greek Salad with cherry tomatoes; then Black Truffle chicken Hunkar Begendi; Cool Souvlaki with pork strip in rice paper; Cannelloni Pastitsio, ground beef and béchamel; Lamb Duet of saddle and cutlet, tzatziki spring roll; Loukoumades, lavender honey, chocolate sorbet; Greek Yoghurt mousse, quince pudding, cinnamon rusks. Coffees.

I may have left some out. There were four of us, but….really. I blame the dark curly haired waitress in the white blouse, the animated company, the heavy rain outside, and the understandable stress of having reviewed some papers on dieting.

Booking recommended.

Wednesday 20 November 2013

Diet is an IQ test

It may be a hazard of working in a medical school, but from time to time I have felt the need, on the basis of some apparently valid research, to change my diet somewhat. At one stage that involved eating more fibre (unpleasant results and unnecessary investigations) eating much more fruit (same, plus higher bills) reducing the amount of red meat and bacon (increased gloom, slightly lower bills),  taking and not taking vitamins, and other similar variations.

Come to think of it, I was probably responding to the media rather than any of my colleagues, since no-one in the staff dining room took any notice of such things. It was also there that I learned the basic metabolic formulas which revealed that humans are efficient and burn relatively few calories in normal daily activities, so if you want to keep slim you have to reduce your food intake.  The key to avoiding being fat was: Eat less.

I have tried to cover these issues in a previous post “Fat is an intellectual issue”

If a good diet leads to good health, then any person of normal intellect should be able to work out what is required to maximise their chance of a healthy and long life. In modern life, working out what to eat is an IQ test.

Now we get two useful publications to assist us in making these decisions. The first is a paper in the New England Journal of Medicine by Casazza et al. (2013) entitled “Myths, Presumptions and Facts about Obesity”

With a title like that, the paper is riding for a fall. I cast a belligerent eye on this 20 author publication, expecting the worst. They condemn, for lack of evidence, the following myths (beliefs held to be true despite substantial refuting evidence):

1) Small sustained changes in energy intake or expenditure will produce large, long-term weight changes.

2) Setting realistic goals for weight loss is important, because otherwise patients will become frustrated and lose less weight.

3) Large, rapid weight loss is associated with poorer long-term weight-loss outcomes, as compared with slow, gradual weight loss.

4) It is important to assess the stage of change or diet readiness in order to help patients who request weight-loss treatment.

5) Physical-education classes, in their current form, play an important role in reducing or preventing childhood obesity.

6) Breast-feeding is protective against obesity.

7) A bout of sexual activity burns 100 to 300 kcal for each participant.

In deference to those of my readers who cannot read the whole paper because they are about to have sexual intercourse: in reality it burns only about 14 calories more than watching television, apparently.

Anyway, all 7 of these claims have been refuted by reasonable studies. Having got rid of 7 myths, they then tackle 6 presumptions (widely accepted beliefs that have neither been proved nor disproved):

1) Regularly eating (versus skipping) breakfast is protective against obesity.

2: Early childhood is the period in which we learn exercise and eating habits that influence our weight throughout life.

3: Eating more fruits and vegetables will result in weight loss or less weight gain, regardless of whether any other changes to one's behavior or environment are made.

4: Weight cycling (i.e., yo-yo dieting) is associated with increased mortality.

5: Snacking contributes to weight gain and obesity.

6: The built environment, in terms of sidewalk and park availability, influences the incidence or prevalence of obesity.

In pure Scottish: these are not proven. Probably best forgotten, in my view, but new evidence may yet emerge in their favour.

What do they list as proven facts? Moderate environmental changes can promote as much weight loss as medical drugs; reduced energy intake reduces weight, but dieting is difficult; exercise increases health regardless of weight; sufficient exercise improves weight maintenance; parents need to be involved in helping overweight children; regular meals promote weight loss; weight loss can be achieved by sustained taking of medical drugs; in appropriate patients bariatric surgery results in long-term weight loss. 

So, eat less, though eating less is difficult, and in the US both drug companies and surgeons are after your money, some of which you can save by eating less in the first place.

They reflect: “When media coverage about obesity is extensive, many people appear to believe some myths simply because of repeated exposure to the claims.[] Fortunately, the scientific method and logical thinking offer ways to detect erroneous statements, acknowledge our uncertainty, and increase our knowledge. [] Moreover, we often settle for data generated with the use of inadequate methods in situations in which inferentially stronger study designs, including quasi-experiments and true randomized experiments are possible. In addition, eliminating the distortions of scientific information that sometimes occur with public health advocacy would reduce the propagation of misinformation.”

My preliminary impression is that I warm to these authors, all 20 of them, when they are knocking down the myths and presumptions, but I think they pull their punches on the facts section. They stress that wanting to go on a diet and being told to go on a diet doesn’t usually result in the sustained maintenance of the diet. Fine, but we are talking about obesity. They note that “energy reduction is the ultimate dietary intervention” and that nothing else works unless “accompanied by an overall reduction in energy intake”.  The English for that is: “Eat less”. Pity they put it as Fact 2, and buried it somewhat as an implication. Get that fact in your mind and you will have no need for surgeons. The way the authors handle it, that crucial fact has little impact. I cooled to them at the end. They started well, and then petered out.

Next up is Prof David Colquhoun, who focuses his sceptical eye on the broad range of diet claims and briskly asserts: We know little about the effect of diet on health. That’s why so much is written about it.

First off, Colquhoun draws attention to the long list of conflict of interests listed by the Casazza paper authors above, including many food manufacturers, which he says complicates an already messy field.  He goes on to quote with great approval a paper BMJ 2013;347:f6698 doi: 10.1136/bmj.f6698 (Published 14 November 2013) by John Ioannidis. I will summarise the main points of the suggested references, with additional comments.

Most nutritional studies are observational, not experimental, and depend on questionnaires. There is always a nagging doubt as to whether every bacon sandwich and slice of chocolate cake will be faithfully reported, under the strain of recalling in vivid detail every lightly boiled cabbage and spoonful of cottage cheese.

Epidemiologists sometimes forget that people differ. Some are compliant boy scouts, some irresponsible spirits who don’t return questionnaires or follow instructions. Humans differ in intelligence and personality, but these considerations do not normally darken the door of diet epidemiologists. As far as they are concerned, people are what they eat, or become so after a decade of imprudent gluttony. Indeed, the meme “you are what you eat” seems to have had a great impact, despite being demonstrably false. Curious, the power of ideas, even stupid ones.

Even when semi-controlled trials are carried out, there is no way to ensure compliance, fall out from trials is rife, and sometimes the comparison conditions have to be made palatable by being only slightly different from the local cuisine (such that the low fat option is  37% fat, not the usually recommended 10%).

Then come all the odd and implausible results, such as that those that suggest we can halve the burden of cancer with just a couple of servings a day of a single nutrient (insert your favourite health food here). Miracle claims of this sort circulate widely in peer reviewed journals.

The other gripe among the cognoscenti? You read it here first. The sample sizes are too small, not followed long enough, and with high levels of sample attrition. Whoever you are, you cannot get round sampling theory. Samples of about 70,000 followed until death (with a proper link to death registers) will be required to identify even a few general patterns in diet which might account for a 5-10% increase in risk. If the studies are to mean anything, IQ, personality, sociological and occupational variables will have to enter the mix, and participants will probably have to be paid to stick to the course, and put up with random visits of inspectors looking in the fridge and the medicine cabinet. Count me out. So, although these correct and worthy researchers want controlled studies, they are not going to get them. Liberty will triumph over the food police.

After much thinking about how we can ever prove causality between diet and health, Colquhoun concludes that the only thing we can say at the moment with the remotest level of confidence about diet is:

Don’t each too much, and don’t eat all the same thing.

In shorter words,  eat less.

That advice should be clear to all levels of intellect.

Disclaimer: Dinner was a microwaved Indian meal with curried chicken Madras 163, rice 269, potato cauliflower spinach 147, and nan bread 138, so a total of 717 calories, and then there was a large portion of home-made apple crumble and yoghurt. So, as the labels prove, a total of 717 calories.

Monday 18 November 2013

Can The Economist be trusted on intelligence?


I used to trust The Economist, though I recognised that they were reluctant to discuss human intelligence. It does not fit their world picture, so they generally ignore it. Their line is that human skills are entirely mediated by environmental causes, and they follow this view with relentless enthusiasm.

Their most recent offering is true to form: “Ethnic-minority pupils in England are storming ahead. Every ethnic-minority group that trails white Britons in GCSE exams, normally taken at age 16, is catching up. Bangladeshis used to perform worse than whites; now they do better. Indians have maintained a huge lead. All this despite the fact that ethnic minorities are poorer than average. Control for that, by looking at pupils who are entitled to free school meals, and all ethnic-minority groups now do well.”

They draw a chart to make the point crystal clear:



First, this chart is designed to make any changes as dramatic as possible. It strongly suggests that white British students have made no progress, but have been overtaken by some minorities, or are about to be overtaken by other ethnicities. There is an explanatory legend “Percentage point difference from the mean” at the top of the graph but most readers will just look at the lines, which appear to tell their own story.

“Control for…free school meals” Where have we heard that before? This is the sociologists’ fallacy: that differences in wealth are entirely due to external causes and are not in any way the consequences of prior differences in intelligence and personality. It is assumed that differences in wealth are outside your agency.

The gap between the free schools meals students and the rest depends on the exams taken and the grading of those exams, but an Economist graphic which shows “gap closing” after a correction for free school meals cannot show that. Also obscured is a highly relevant factor: if these results are to be believed, then there has been a massive increase in scholastic ability between 2007 and 2011. Can’t see that? Of course not, we need to go further back to the raw data, or more precisely the slightly less cooked data from which the graphic was derived.

The Economist reference to the Department of Education is rather vague, and has taken me some time to track down, but here are the actual GCSE results, with the 2007 results in light blue, and the 2011 results in purple.




The old “white British” level for 2007 is shown by a solid line, the new “white British” level shown by a dotted line. As you can see, either scholastic ability has zoomed up from a 45% pass rate to a 58% pass rate in 4 years (perhaps as a result of surreptitious genetic manipulation of the student population, a transformation in teacher’s charisma and ability, or something special in the water supply) or the test has been watered down over that period, particularly for lower achievers. Notice that every single ethnic group has gone up, particularly those who were doing badly before. Not the Chinese, however. (By the way, the Economist drops the Chinese entirely, in a case of ethnic ignoral). What has gone wrong with the Chinese? Smoking dope and playing too many computer games? Bad role models? Rap videos? Or does the new test not have enough scope for already bright scholars to show their high level skills? We are talking pass rates, after all, not actual marks. Getting 90% on a test and 50% on a test gets the same mark on this graphic: your pass was C or better.

Now consider the following possibility: if you suddenly decide to give everyone an additional mark for holding a pencil you will get a higher pass rate. The pencil bonus will have least effect on the brightest students who are already getting high real scores. However, it will make everyone else look good, including the teachers. A mark for holding a pencil would be too blatant. A few more marks for giving very simple answers will have the same effect. The simplest tricks are the best. The Economist article and Department of Education report are predicated on these being real gains.

The strong suggestion that the exams have got weaker is sustained by the findings on free school meals. If needing a free school meal is an indicator of low ability as well as bad luck, then one would expect smaller differences between “high ability/good luck” students and “low ability/bad luck” students on easy subjects (all will tend to get prizes) but larger and continuing differences on harder subjects. The data bear out this interpretation.

“The attainment gap between the proportion achieving 5 or more A*-C grades at GCSE or equivalent including English and mathematics GCSEs is 27.4 percentage points – 34.6 per cent of pupils known to be eligible for FSM achieved this indicator compared with 62.0 per cent of all other pupils. There has been a very gradual narrowing of the attainment gap from 27.9 percentage points in 2006/07. “ (My note: this narrowing is probably just measurement error).

“However the attainment gap between the proportion achieving 5 or more A*-C
grades at GCSE or equivalent has narrowed faster by 8.7 percentage points between 2006/07 and 2010/11, with 64.6 per cent of pupils eligible for FSM achieving this indicator in 2010/11, compared with 83.0 per cent of all other pupils.”

It’s a bit hard to work it out, isn’t it? The last paragraph shows that if you measure achievement by easy subjects 83% of able students pass, and even 65% of less able students pass, so the “gap” is 18 points and over 4 years has narrowed faster. If you make the criterion just a little harder, by ensuring that students exams take English and Mathematics, which in normal educational systems would be considered the purpose of sending children to school in the first place, then 62% of able students pass, but only 34.6% of less able students, a gap of 27.9% and that gap stays solid.

So, the true finding is as follows: no closing of the gap if you require students to read, write and count, but less of a gap and more apparent progress if they are tested on less demanding skills! What does the Department of Education do next? It “corrects” for the real gap revealed by the English and Maths exams by making an adjustment for school meals, on the assumption that this measures poverty and not any ability differences. (I hope you are still with me. I may have lost the will to live while going through these results, so I do not blame you.  I think they have been written so that no-one will actually read them, but will have to rely on newspaper summaries.)

How do they do the adjustment? I cannot find this described in the technical appendix, but since they fall for the sociologist’s fallacy they will have done the following: they will have assumed that poor kids would have done as well as rich kids if they had just happened to be rich, so they bump up the results for each ethnic group in proportion to the number of kids in each ethnic group who are poor. So, if most of the children in a particular ethnic group are poor, they get a big boost from this adjustment. Of course, both parents and children may be poor because they have low ability, and cannot easily work in a technological society and/or do not save whatever they can earn, but that possibility is not considered. The “adjustment” or “correction” is made, and the desired argument is “proved”.

My other observation is that there is only one group that really stands out, and they are the Irish travellers and Gypsy/Roma. Numbers are very small, but it is clear that schooling is not their thing. There is intelligence test data on these groups, which would suggest low ability, but that is for another time. Drop those few students, and the significant finding is that Chinese and Indians and White and Asian students are leading the pack. Of course,  the “proportion of students achieving a particular level” measure is crude. The actual results would be more informative, as would be the subjects studied. Some are easy, like A level Psychology and Sociology for example.

In summary, if you look at the detail, some of The Economist story is borne out, but the detail reveals that these exams give us only a partial glimpse as to what is happening with ethnic minorities, because the pass rates for all students have been rising so fast. By making the White British score an apparent unchanging line they have obscured a fundamental problem with using GCSE scores to track scholastic progress. PISA and TIMSS scores do not show commensurate improvements. Furthermore, the “correction” for free school meals is based on highly questionable assumptions. I am not denying that Chinese children are bright, and that the selection of Indian children of commercial classes who made it to Britain are also bright. The sad truth is that if you make exams too easy, then you may well lose out when some students make real gains: the test has become too soggy to measure real achievement.

Disclaimer: If you can find better and further particulars about these “adjustments” I am happy to hear from you. That includes the Department of Education.

Sunday 17 November 2013

Was the Scientific Dishonesty Minister trying to suppress population estimates?


A general bemusement is now spreading through psychometric  researchers about the actions of the Danish Ministry of Science, Innovation and Higher Education, and its fearsome “Danish Committees on Scientific Dishonesty”. In a marginal aside, I suppose we should be mildly grateful that any Dane who is trying to be dishonest is going about it scientifically, but back to the main point, the whole farrago gets more absurd the more we learn about it.

So far, the Danish speakers who have looked at the judgment of this Committee find that this investigation, about which we do not yet understand the basic processes (I have asked the Minister for a prompt official translation into English for an international audience) have identified two counts on which their condemnation is based (four other accusations were turned down) namely: first, that Nyborg was a single author, and that although the committee accepts he offered joint ownership to a colleague who turned it down, it finds it proved to their satisfaction that his claiming to be the single author was dishonest; and second, that his reference to a data base was indeed to that data base, but that Nyborg did not also reference a correction to population growth estimates according to population age structure, though they accept that Nyborg has already submitted a note to the relevant journal on this omission. At the moment we do not understand why they did not simply require that these two aspects be dealt with in an erratum note. Why ask for the withdrawal of the entire paper, even assuming that government committees should be getting involved in these matters?

Commentators are wondering quite what is going on, because if these strictures are applied through academia, we will all be withdrawing papers, frantically contacting old collaborators who helped with tasks but did not ask for authorship, and making penitential pilgrimages to Denmark. Naturally, researchers of a more sour disposition might now choose to take the Danish Dishonesty Accusation route, and denounce troublesome rivals and old academic foes, in the sure knowledge that the two year process will keep them out of circulation for a while. Come to think of it, I could probably “take out” Nisbett, Aronson, Blair, Dickens, Flynn, Halpern, and Turkheimer for their egregious misquoting of McFie (1961) (See “On best understanding Nisbett” on this blog). “Your Honour the Minister for Scientific Dishonesty, I beg leave to arraign before your Committee the afore-named miscreants for having said that McFie (1961) achieved such results as he did after “a few months of Western-style education” when in fact those slight but interesting changes were achieve only after over two years and four months of technical college instruction. I ask that they they be condemned without appeal, and made to withdraw their paper”.  Curious how quickly one can warm to themes of academic revenge. Before this gets out of hand, may I ask readers to contact the above named authors, and explain to them that the publication of a simple erratum statement, plus the usual generous donation to this blog will sort the whole matter out, without bloodshed?

With this in mind, here is Nyborg’s abstract, saying that his paper “provides a demographic analysis of what happens to modern sub-fertile high-IQ Western populations when Internal Relaxation of Darwinian Selection (IRDS) combines with External Relaxation (ERDS, in the form of super-fertile low-IQ non-Western immigration) into Double Relaxation of Darwinian Selection (DRDS). The genotypic IQ decline will ruin the economic and social infrastructure needed for quality education, welfare, democracy and civilization. DRDS is currently unopposed politically, so existing fertility differentials may eventually lead to Western submission or civil resistance.”

The thesis is certainly a matter of contemporary interest, and it is expressed in a highly dramatic fashion. (Boring titles are usually better in academia). Western populations are relatively high IQ with respect to the global norm, though they are below the estimates for China, Japan and Korea. They have low fertility, mostly at around replacement value, sometimes below. They have ageing population structures, are wealthy and have generous welfare provisions which generally far exceed average earnings in the rest of the world.  Most of the countries which supply immigrants to Europe have lower IQs and educational attainments, sometimes much lower, and less generous or non-existent governmental welfare systems. They have higher fertility rates, and much younger population structures.

So,  Nyborg continues, if you take any European country with high IQ, low fertility and generous welfare systems you may get the first whammy, dysgenesis. This is the old spectre which haunted the Victorians: that the lower class energetic breeding of relative dullards would swamp the higher intellect, refined upper classes. This hypothesis has usually been dismissed with a sneer, but the arithmetic of the heritability of intelligence makes it theoretically possible. Even with regression to the mean, if lower IQ couples have more children than higher IQ couples, then the population average will drift down, albeit slowly.

There was only one thing against this hypothesis, and that was the data on intelligence. Far from drifting down, it was clear by the 1940s that IQs were rising. This was against expectation. By the way, if there had been a prohibition against eugenic research, this might not have been found out! It goes to show that research often turns up unpredicted results. So, the actual finding was of a secular rise in intelligence, in itself the subject of much current interest.

Writing some time after the Nyborg paper, Woodley was the first to argue that historical reaction time results supported the identification of a significant dysgenic effect, hence the interest in his work. (Hence also the interest in finding out whether the young man will come out for the 5th round of his big match. The te Nijenhuis and Murphy corner assure me he is indeed ready to storm out again, and predict he will vanquish the opposition). That matter will be dealt with here, as will the upcoming special issue of Intelligence on The Flynn Effect Re-Evaluated. Verily, you are reading the right blog for the latest research in intelligence.

Anyway, the Nyborg thesis continues thus: you have rich countries encouraging the duller lower class to have large families, thus driving down native national intelligence, and then you go for the double whammy, because those same wealthy nations are absolutely relaxed about letting in lots of low IQ immigrants from foreign countries. A portion of that lower ability is very likely to be due to genetic causes, or is at the very least difficult to shift by educational interventions, so when these low IQ immigrants have children they will be similarly low IQ citizens, or only slightly above their parental levels. Thus the European nations slide into dullness, with large number of dull locals and large numbers of even duller foreigners. End of Western Civilization.

I think you may detect that I present the thesis in a somewhat doubting, not to say disparaging way.  The problem is, what if Nyborg is right? At the very least, we need to look at the argument in more detail, and with a critical eye. There is a link to his paper here.

To the surprise of some, differences in intellect between persons and groups are well established. It is likely, on balance of probability, that genetics plays a part in all human differences, and that genetic groups are no exception to that rule, indeed they may be the best place to start looking for the genetic causes of intelligence differences. (It will be interesting if genetic enquiries fail to come up with any replicable results, since it will certainly give the environmentalist position a considerable boost).

If you look at his paper, you will see that Nyborg tries to calculate how many immigrants will enter Denmark, and how many children they will have, and that he does all this whilst being aware that predictions about fertility are likely to be wrong (see below). The prediction game is highly error prone, so we cannot be sure that current projections are reliable guides to the future. Immigrants may take on the mores and habits of the locals. Local Danish descent couples may increase their family size, and Danish descent professional couples might start having very large families. Schools may yet find ways of increasing ability in less able groups. Denmark may flourish as the ancient tribe of Danes (closest genetic cousins to the English) intermingle with other genetic groups, exploiting hybrid vigour.  However, the data on the convergence of immigrant scholastic abilities with those of local children is not supportive of the most optimistic scenario. Have a look at the Meisenberg and Woodley paper in the special issue “Are cognitive differences between countries diminishing? Evidence from TIMSS and PISA”, which predicts convergence of developing world countries with rich world countries somewhere between 70 years or 340 years or never, depending on the tests used. You could also look at Rindermann and Thompson “Ability rise in NAEP and narrowing ethnic gaps?” PISA has international data for immigrants, showing that second generation immigrants usually achieve some closing of the scholastic gap with the locals but significant differences remain. In summary, Nyborg has strong supporting data on the scholastic front, and the currently higher fertility of immigrants is also documented, though of course that might change.

On that very matter, Nyborg probably underestimated the pressure on Europeans to share their territory with non-European genetic groups. At this stage I should say that for years I have been supporting the UN line, which is that if you provide women with access to education, by their own volition they will have smaller families. I saw this on their posters in the 1980s, and it influenced me. I argued confidently that the rate of population increase was falling.  Nyborg used the 2007 UN estimates for population growth, the latest available when he wrote his paper. The UN 2012 revision released in June 2013 is the institutional equivalent of an academic erratum. Their earlier predictions over-estimated the speed with which all women would reduce family size. It seems that the UN did not distribute sufficient posters to tell African women what was expected of them.

New York, 13 June—The current world population of 7.2 billion is projected to
increase by almost one billion people within the next twelve years, reaching 8.1
billion in 2025 and 9.6 billion in 2050, according to a new United Nations report,
World Population Prospects: The 2012 Revision, launched today.
Most of the population growth will occur in developing regions, which are projected
to increase from 5.9 billion in 2013 to 8.2 billion in 2050. During the same period, the
population of developed regions will remain largely unchanged at around 1.3 billion
people. Growth is expected to be most rapid in the 49 least developed countries,
which are projected to double in size from around 900 million inhabitants in 2013 to
1.8 billion in 2050.
At the country level, much of the overall increase between now and 2050 is projected
to take place in high-fertility countries, mainly in Africa, as well as countries with
large populations such as India, Indonesia, Pakistan, the Philippines and the United
“Although population growth has slowed for the world as a whole, this report reminds
us that some developing countries, especially in Africa, are still growing rapidly,”
said Wu Hongbo, the UN Under-Secretary-General for Economic and Social Affairs.

So, the UN has made an error of a billion persons. Some revision! Another case to be taken before the Danish Minister for Scientific Dishonesty?

Professor Richard Lynn has written to the Danish Minister thus:

I am surprised to learn that proceedings are being taken against Professor Helmuth Nyborg with accusations that there are statistical errors in his paper The Decay of Western Civilization: Double Relaxed Darwinian Selection, printed in 2012 in Personality and Individual Differences, vol. 53, issue 2, 118-125.

In my judgment the paper is sound. He estimates that by 2072 around 60% of births in Denmark will be to people of non-Western origin, and that indigenous Danes will be a minority of the population by 2085. He estimates the average IQ of the immigrants at 86, and the IQ in Denmark in 2085 will be 90.

The estimate that indigenous Danes will be a minority of the population by 2085 is similar to the estimate for Britain made by Professor David Coleman, Professor of Demography at the University of Oxford, who predicts that the indigenous British will be a minority of the population by 2056. This prediction is based on what he calls “the standard scenario” and is derived from estimates of the net migra­tion of non-European immigrants and their mortality and fertility, Similarly, in the United States, the Census Bureau’s projection that whites will become a minority in the United States in the year 2043. Thus, there is nothing at all remarkable about Professor Nyborg’s estimate that indigenous Danes will be a minority of the population by 2085.

Professor Nyborg’s estimate that the average IQ of the immigrants in Denmark is 86 (as compared with 100 for indigenous Danes) is based on solid evidence. It is obvious that as the number of the immigrants increases the IQ of the population will decline. His estimate that the IQ in Denmark in 2085 will be 90 is reasonable.

Richard Lynn, MA, PhD Cambridge

Professor emeritus of Psychology, University of Ulster.

Ref: Coleman, D. Projections of the ethnic minority populations of the United Kingdom 2006–2056. Population and Development Review, 2010. 36, 441–486.

Perhaps it is simply the replacement of the local tribe with another from afar which makes for uncomfortable reading in government circles, linked to disturbing evidence that these foreign tribes do not achieve the same levels of local wit even after two generations. Furthermore, the foreign tribes are not following the European example of reproductive restraint with quite the speed and acquiescence which had been expected of them. No people actively search out minority status in their own country. From a global perspective, if you won’t populate your own territory, others will. The projections being made might be wildly wrong, but at the moment it seems possible that Europeans, by their own volition, may finally achieve European Exceptionalism, if only in the sense that eventually there may be, proportionally speaking, exceptionally few of them.

Or perhaps it was a common room row about the correct way to reference UN statistics?

Thursday 14 November 2013

My letter to Scientific Dishonesty Minister


Dear Minister Morten Østergaard

I write to you in some alarm, hearing that in Denmark there is a procedure in which your Ministry establishes committees which judge whether a researcher is behaving in a scientifically proper manner, and that these committees may demand the recall of published papers.

The usual practice is to debate these matters in scientific journals, in which critics make their points and the author can make their replies. As part of this process authors may alter their views, correct errors, and provide further explanations and data. Critics may concede that they have misunderstood a point, may alter their criticisms, or may reserve judgment until the finding has been replicated. This may require many exchanges of views, many publications, and many years. As part of this process other researchers gradually come to their own conclusions as to which findings can be relied upon. Typically, arguments about major issues in social science may last for decades.

It is unusual in academic circles for one scholar to accuse another of scientific dishonesty. There is a strong preference for testing one argument against another, and assessing the arguments without attacking the person. When much of what we research is uncertain and subject to different interpretations we need to be respectful of different opinions, particularly when those opinions are opposed to our own preferences and beliefs. We want scientific debates, not religious ones.

Sadly, there are occasions when a researcher fabricates results. When this is suspected then a most careful academic enquiry is carried out, excluding any persons who are known to be involved in arguments with the scholar, and with the accused person being given every opportunity to explain themselves. It is usual for them to have legal representation, and a right of appeal if they can find procedural or evidential flaws in the decision. If such fundamental dishonesty is proved then it is usual for the Journal to withdraw the paper. Their University or Institution may then decide to take disciplinary action against the dishonest author.

In summary, both Journals and Universities have procedures to deal with the rare cases of scientific dishonesty.

Appointing a Committee in a national Ministry seems an unwise and potentially dangerous precedent. Ministers will have to ensure that they appoint experts of very high standing in the very many fields of academic endeavor for which there are scientific journals. That will not be an easy task for any national Ministry since research is now international, and many fields of research are extremely specialized. There is also the problem of ensuring that the committee members are not compromised by prior disagreements and conflicts. Journals usually draw upon an editorial board and a set of agreed reviewers, setting aside any who are known to have an adversarial history as regards the scholar in question. The accused person must have legal representation, and there must be recourse to appeal for procedural and evidential shortcomings.

I now turn to the specific case of Professor Emeritus Helmuth Nyborg. I have not been able to read the conclusions of the committee in your Ministry, because it is published in Danish. Of course, a Danish criminal court would publish its judgment in Danish, but this is an example of the problems which arise when a political and legal process is used in science. English is now the language of science. Professor Nyborg publishes in English to an international audience. At the very least, given the impact on international science of your committee, you should have an English language version of the judgment available for all scholars to read. I hope you will be able to provide an official translation promptly. I am particularly interested in finding out how you took evidence and evaluated it, and whom you called to participate in the process. I would have been willing to give evidence.

I have read Professor Nyborg’s replies and explanations and although I do not have access to an English version of the conclusions, the judgment of the committee seems extremely strange to me. The authorship issue has been explained by Professor Nyborg. A colleague did not want to be a co-author. This happens. Even more common is a colleague who demands to be a co-author, despite having contributed little apart from access to some data. As you will be aware, there are often disputes about the order of precedence of authors. His disputed reference is to the correct data set, but did not add a simple birth rate calculation which has now been referenced. The Nyborg case is that he did not explicitly state a correction he had applied to birth rate calculations. That can be handled by a published clarification, which has already been done. This happens all the time, and improves our research.

If these judgments were to be applied to research in Denmark and internationally, few scholars would be able to avoid appearing before your committee.

Contrast this with a case in Holland in which a researcher fabricated his results. He was dishonest. Under the usual procedures the university and the journals made that fact known to the academic community. His papers have been investigated and are no longer relied upon by scholars.

I hope you will abandon your current structure, withdraw these inappropriate interventions, and not determine scholastic debates by recourse to Ministerial committees.

Helmuth Nyborg gets Watson’d


Helmuth Nyborg is a Professor of Psychology in Denmark who does psychometric research and publishes widely (about 97 papers) in peer-reviewed international journals. He is a firm proponent of the genes plus environment view of human behaviour. He has fallen foul of the environment-only view, to which I will give the appellation “blank slate-ism”.

He has just been stitched up by three critics in one of the The Danish Committees on Scientific Dishonesty which lurk in The Ministry of Science, Innovation, and Higher Education. In the midst of all this horrible nonsense, which has already caused him a lot of trouble and cost him his Emeritus status, I cannot help but be distracted by the funny names education departments give themselves. Innovation? I suppose a Committee for Public Safety is an innovation for Denmark, but the Jacobin terror got there first.

The three pursuers have found him guilty of two crimes: “that the defendant had committed scientific dishonesty by appearing as the sole author of an article and by including a reference which did not support the data it indicated to support.” There is no appeal allowed. Helmut writes to me, in great detail poor fellow, showing that he offered co-authorship to a colleague who did not accept it, and that the reference was to the correct dataset, but should have included a note on a technical correction about birth rate projections which makes no real difference to the results. You can get the very much fuller account from him (see email address below).  I shudder to think what this committee could do to any authors of any published paper if it classifies omissions of this sort as “scientific dishonesty”.

Is there a back story? Yes, Helmuth got on the wrong side of a colleague at his university. They applied for the same job years ago. The other guy got the job. Helmut, who had 40 publications at that stage, which was far more than the other candidate, protested. They have been on very poor terms ever since. Incredibly, this guy was one of the three members of the committee. The other two are also on public record as being hostile to him. Publication rates for two of them are 0 and 0, and 32 for the other one, so he is hardly up against stellar scholars.

More of a back story? Helmuth thinks we are going to the dogs in a hand cart, and that we are showing dysgenic fertility in the sense of reverse Darwinian selection. All this is possible, and the impact on nations depends on assumptions about birth rates and intelligence in the next decades, but it is not a popular story in some quarters. 

More back story? Helmuth is unusual in psychology, in that he had a period in his life when he had a real job. He was a sailor on merchant ships, and on the long sea journeys began to catch up on an education he had never had as a young man. He went into psychology and made a new career for himself, initially in the perception of the rod and frame illusion and later in more general behavioural differences. He still has some of the blunt manners of a man who gets things done. I would let him captain my ship through pirate waters, but I would not elect him to be Chairman of the Diplomatic Committee for the Management of Academic Sensibilities and Polite Evasions (and Innovation).

Is there even more of a back story?  This has the stink of a common room feud. Has your institution ever had such a thing? Of course not, but surely if you are being tried for your academic life you deserve to appear before an unbiased set of assessors, and have full legal representation, and not be judged by accusers who have strongly opposed positions in their politics and world outlook, and have personal animosities to boot.

So, there are two people you need to contact to get their side of the story and to send emails of comment.

One is a professor who has retired from his university, and continues to publish work in psychometry, who would like your support, and who wants to show you his defence. Here is his website which lists his publications: The Wikipedia entry on him is frequently hacked by his critics, so is not reliable.

Prof Helmuth Nyborg

The other is a politician, to whom you might like to write, urging him first to publish the judgment in English, the international language of science, so that we can read this extraordinary Court judgment; but most of all to urge him to let academics sort out their differences in academic journals, where claim and counter-claim can be evaluated in the usual fashion.

Morten Østergaard, Minister for Research, Innovation, and Higher Education, Denmark

Odd world, isn’t it!

Wednesday 13 November 2013

Crack cocaine and American dreams


Hallam Hurt and colleagues have kindly sent me more of their recent publications, one of which has some relevance to their reported claim that “poverty causes more problems than crack cocaine”.

Handzel, Brodsky, Betancourt and Hurt “Longitudinal Follow-up of Poor Inner-city Youth Between Ages 8 and 18: Intentions Versus Reality” Pediatrics; originally published online February 20, 2012.

It looks at African American children’s dreams about their future, and the reality of the actual outcomes, and attributes the greatest effect to exposure to violence and poor home environments. The paper makes sad reading. At age 9 the children had upbeat expectations,  in line with the American dream, the founding fathers effect of Protestant self-improvement and general good natured optimism. No low expectations here. No lack of self-esteem. By age 18 reality had intervened, and half of those cheerful childish expectations had been dashed.

At age 9, 94% of participants felt it unlikely they would try marijuana; 93% felt they were unlikely to get arrested; 92% felt they were likely to attend college or trade school; 81% did not know one could become pregnant with first-time sex (this last one is ignorance, not over-optimistic self perceptions). Age 18 33% had used drugs, 33% had been arrested, 19% had dropped out of school, and 20% had become parents. 56% experienced at least one of those events. No relationship was found between childhood intentions and the eventual documented outcomes. So, although the popular mantra is “you can become whatever you want to be” the chances of that coming true are distressingly low.

The authors conclude their paper thus:

“During childhood, our cohort of poor, inner-city children were idealistic regarding
their future. However, by the ages of 16 to 18, more than 50% of these teens already had at least 1 TAE. Factors most strongly associated with TAEs were greater exposure to violence and a poorer home environment, both early childhood environmental factors.”

My reading is that their conclusion is partly right as far as it goes, but the actual results suggest that their environmental interpretation is far from being the only one possible. For example, let us take the statement that 56% had experienced a “trajectory altering event”, the odds of such an event increasing with greater exposure to violence and a poorer home environment. The phrase “trajectory altering event” suggests an external force like a meteorite, but on examination this turns out to be things that the teenagers have got themselves into: using drugs, getting arrested, dropping out of school, and failing to use contraception when they were in no position to raise a family. Crucially, it is NOT an independent risk factor. It is consequence of their failure to see the deleterious consequences of their own actions. So, the factors are “strongly associated” but are very unlikely to be causal, and are more likely to be associated effects of other primary causes.

What do the authors think has caused this horrible reverse in fortunes? The authors identify violence and poorer home environments as increasing the risk of a “trajectory altering event”. Below is their Table 1 showing the difference between those who had a good outcome and those who did not,  or as they describe it, “no” and “some” trajectory adverse events:


The P values are given, but let us rank them by effect size (difference in means as a ratio of the standard deviation of those without TAEs): exposure to violence 1.0, home environment 1.02, IQ 0.41 and the others seem too small or given as categories.

The authors then do a logistic regression, and come up with the following odds ratios.

Gender                              10.21 sig

Caregiver using drugs       3.66 non sig

Exposure to violence         1.14 sig

Full Scale IQ                      0.96 non-sig

Home environment           0.77 sig

As regards discussing findings in terms of p values, this is the issue to which Gigerenzer has drawn attention. We researchers tend to use p values in a slavish fashion, as part of a ritual. Ranking findings by effect size (rather than computing fluke probability) is often more illustrative of the features of the sample in question. Researchers need to tell us about their samples in plain language, and then give the basic findings in terms of effect sizes. Even a simple correlation matrix would be some help (and in that instance the p values could be mentioned). After that, if it really seems worth while, they could try structural equation modelling.

The fact that boys are one order of magnitude more likely than girls to get into trouble is well known. “Caregiver using drugs” at 3.66 fails the significance test, yet suggests an effect might be found in larger samples, and is certainly a putative causal variable. The violence measure at age 7 does not distinguish between violence in the home and violence outside it, but it would have been worth while giving those scores separately. Violence in the home tends to be particularly damaging, because it denies the child any place of safety.

Now let us look at the language being used. “Exposure to violence” is neutral, but suggests the children were walking down the road and some external event occurred. Might we be dealing with violent families? We need more data, but it is possible that this is what is happening. How would you say, in modern parlance, that a child was being brought up by a family in which the parents were on drugs and paid little attention to the child and were violent to each other and/or to the child? Problem family? Dangerous family? Careless family?  All these make it clear that parents were failing to care for children in their charge, if not in their love. “Vulnerable family” gives a clue, without giving away too much. Some researchers think it would be better to try to distract readers from this reality, and say that all problems could be traced to damp houses with peeling wall paper. “Poor home environment”? That should cover a multitude of sins. It put the problem outside of individual decision making.

Looking at the paper as a whole, on the positive side, the measures of childhood obtained from a longitudinal study, and are not retrospective. Less happily, there has been a high drop-out rate, particularly among boys. The sample size of 79 is small and so constrained by the selection criteria that it is hard to draw strong conclusions. We need comparison groups and larger samples to have confidence in the findings. For example, one could look at other poor children, different ethnic groups,  including white children of similar IQs in order to tease out possible causes. Other samples of white children seem to show more congruence between childhood expectations and behaviour. In general, arguing from within small samples tends to be error prone when dealing with large questions.

Let me be clear. I am in favour of clinical samples being followed long term. The authors are trying to pick out potential life events which have re-directed the trajectory of children’s lives. That is a worthy thing to do. My gripe is that they haven’t said very much about the possibility that bad parenting is a major factor. In this low intelligence group even a 5.2 IQ point difference has had an effect on adult outcomes, in that the slightly higher intelligence children are less likely to mess up their lives. To their credit the authors discuss this in the context of early intervention studies, of which I am perhaps inordinately fond.

I would simply like the research to be described in a way that gave equal place to nature and nurture. These authors started their study long before collecting genetic samples was the norm, but they seem particular keen to show that the key factors are external and “environmental” whereas they are actually mostly about things which are happening within the family. In summary, this paper does not buttress the claim that poverty is responsible for anything. However, it certainly backs the obvious point that parents should not take drugs and should not expose children to violence. That is a finding of sorts.

Tuesday 12 November 2013

Is young Woodley down for the count?


Things are looking bad for the young challenger Woodley, who came out of the te Nijenhuis and Murphy corner swinging his punches against World Champion Jim Flynn, claiming that, on the basis of Galton’s reaction time data, the lower classes have been breeding too much, casting us all into dysgenic stupidity. His paper “Were the Victorians brighter than us?” (plugged on this blog) got lots of press coverage and, according to the editor, became one of the most downloaded papers on the Intelligence website. No sooner had he landed his eugenic blows on the chin of environmental optimism than there was a heavy weight, four round, concerted counter attack.

When the bell rang for the second round, back into the ring climbed the redoubtable Mighty Champion Flynn, a grizzled New Zealand pugilist, mentored by the great Jensen himself, veteran of many hard slogs, who leads with the left but can also jab with the right, but is always a principled follower of the Marquis of Queensbury’s rules. He hammered Woodley thus: Woodley’s estimated dysgenic rate is three times larger than the theoretical rate on the basis of the negative correlation between IQ and number of siblings throughout the 20th century, making Woodley’s finding implausible. Secondly the absence of a Jensen effect on the Flynn effect is not prima facie evidence that g has been in decline. Thirdly, the secular trend towards declining genius does not evidence the dysgenic trend owing to subjectivity amongst ratings of genius. Fourthly there is substantial methods variance, rendering cross-study comparisons difficult to say the least.  Fifthly, despite the likely presence of dysgenic fertility in Australia during the period spanning 1981 to 2000, there is no decline in performance with respect to another elementary cognitive task (inspection time), which is problematic for the dysgenic interpretation of slowing reaction times.

Seeing the young challenger stunned by his solid punches, in a gracious concession just before the bell, Flynn did his own estimate of the dysgenic trend on Woodley’s data, admitting a smaller but evident 3 point decline overall.

For the third round the Australian Ted Nettlebeck, sun-bleached and hardened by the toil of 20 years of inspection time, jumped into the ring, to land these four Antipodean blows: Firstly, methods variance makes it difficult to compare studies. Secondly, the idea that antagonistic genetic and environmental forces can make intelligence trend in conflicting directions is flawed because the g loading of processing speed measures can only be established by correlating them with the same traditional measures of intelligence which show the Flynn effect. Thirdly, Nettlebeck argues that the decline in simple reaction times cannot constitute a decline in g because the principle causes are showing opposite secular gains. Fourthly, Nettelbeck also criticizes the assumption that simple RTs are associated with high heritability and that they are respectably g-loaded – arguing that both are required for the Woodley argument to work, but that neither is supported by the data.

For the fourth round, the experienced Silverman, a quieter fighter, with a good solid punch, and the original collector of historical reaction times enters the ring. These were his blows: the trend towards the secular lengthening of simple reaction times doesn’t hold when only the male cohorts are considered, in addition to the removal of the Galton datapoint. He contends that the presence of mixed-sex samples containing females (who have slower RT means than men on average) might have skewed the original Galtonian result. He adds that there are too few data points for Woodley to assume a linear relationship with slowing reaction time and year, which would be required to prove a dysgenic trend.

The fifth round brought in the formidable Russian Dodonov and Dodonova duo, an unusual husband and wife combination of legendary aggression, who think nothing of subjecting their own swaddling infant to a crash immersion in intelligence conferences, seeking precociously to add a third fighter to the team. As befits their energetic flurry of punches, they have even partly rebuilt Galton’s equipment to administer a final body blow: they contend that the studies lack comparability, and that controlling for this methods variance effectively obliterates the secular trend towards slowing RT speeds reported in both Silverman (2010) and Woodley et al. (2013). The error sources include stimulus onset delay, long and variable preparatory intervals and key pressure time, which inflate the latency of simple RT performance in more modern studies employing electronic rather than purely mechanical chronoscopes. Using a description of Galton’s pendulum chronoscope, they constructed a somewhat similar instrument, and found that the estimates produced are relatively free of sources of lag that seem to plague the more modern, electronic-instrument-based studies, such as key-pressure time. This is illustrated by direct comparison of the two author’s aggregate simple RT performance on both mechanical and electronic apparatuses – indicating a latency differential of approximately 30 ms favouring performance on the pendulum chronoscope in both cases. That puts puts the tin lid on it, surely? The pendulum method was faster than the contemporary electronic set up.

Te Nijenhuis and Murphy have been yelling encouragement, but the end of the fifth round the plucky Woodley is slumped on his corner stool, and there is only so much the duo can do with sticking plaster to repair their man’s battered countenance. Dutch pragmatism and Irish spirit have their limits. Quite frankly, Woodley’s choosing to box in his habitual long Edwardian jacket and gold pince-nez may not have been the best policy. Has it all been too much for him? Will he be able to stagger out for the sixth round?

The following paper has been submitted to Intelligence and is under review:

Woodley, te Nijenhuis, and Murphy “The Victorians were still quicker and cleverer than us: Responding to a quartet of critical commentaries.”

Whilst I cannot reveal the content until it has been accepted for publication, I can promise you horrific scenes of violence. If you are of nervous disposition, you should avert your eyes.

Saturday 9 November 2013

Have we given the Chinese the keys to the castle?

I hope we know what we are doing. The genetic material of several hundred highly intelligent people in the Western world have been handed over to the Beijing Genetics Institute for analysis. I do not doubt that they are the largest genetic lab in the world, and I do not doubt that they are unhampered by Western taboos about the genetics of intelligence, but it is still a little unsettling to let the Chinese Politburo have first refusal on the application of any results. By the way, I have no inside knowledge about this. It is simply that I believe that if some positive results come out the Politburo will know about them very quickly.

The first communication to the scientific world comes on December 12th at the International Society for Intelligence Research conference in Melbourne. The main presentations are shown on the link above. The actual results are a closely guarded secret. I bet that they will announce that they can account for 40% of the variance in the sample of discovery (the “scary bright” genius population on whom the work is being done) and 1% of the variance in any sample of verification (either the general population or a “normal bright” population). On a discriminant function analysis they may achieve a good degree of separation between the target group and everyone else. This guess is based on the ball-park figures derived from previous research into the genetics of intelligence. It is also possible that they will say that they are still looking at the results and can’t tell the difference between a genius and a performance artist who specialises in education policy.

There are still available places at the conference.

Friday 8 November 2013

Special Issue of Intelligence: The Flynn Effect Re-Evaluated


The paper word now lags well behind the electronic word, yet there is something about paper which confers an extra patina of respectability. Perhaps it is no more than an immigrants’ perception that real knowledge came from the distant North, a fond recollection that well printed books written in English carried the imprimatur of scholarship and the heady whiff of book glue when you opened the stiff covers of a new text, thus entering a new world.

Be that as it may, here is the electronic link to the fact that the Special Issue of Intelligence on The Flynn Effect Re-Evaluated is due out this December, and the link contains all the necessary full bibliographic details.

Thursday 7 November 2013

Reporters and researchers on crack cocaine


My attention was drawn by an observant reader to a flurry of American newspaper reports asserting that poverty was more damaging to children’s intelligence than crack cocaine. The newspaper accounts followed a pattern we have come to expect: the conclusions are trumpeted, the implications explored with excitement, and although the author’s name is mentioned there is no way of tracing the story to an actual publication.

The reported bare bones of the story are that the lead researcher, Dr Hallam Hurt, at the Albert Einstein Medical Center, Philadelphia,  looked at full-term children born to crack abusing mothers, and found that this group was not significantly different from control children in behaviour and intelligence. Commendably, she followed them for 25 years. It seem that the “crack cocaine baby” concerns can be laid to rest. Hurt is clear that using crack is not a good thing, but then goes on to claim that it is poverty which really causes the major impact on these children’s lives. Considering that I have just published a paper on US scholastic achievement, in which we briefly considered the effects of the cocaine epidemic, I thought it worth while to explore these claims.

By way of background, a 1989 study in Philadelphia found that nearly one in six newborns at city hospitals had mothers who tested positive for cocaine. In a city which then had 1.58 million residents, assuming 13 births per thousand residents per year, I calculate there would have been 20,540 births, of which 3,420 were born to cocaine-using mothers. Gathering 10,000 crack babies for a study would take about three years.

Dr Hurt organized a study of 224 near-term or full-term babies born at Einstein between 1989 and 1992 - half with mothers who used cocaine during pregnancy and half who were not exposed to the drug in utero. All the babies came from low-income families, and nearly all were African Americans. The study enrolled only full-term babies so the possible effects of prematurity did not skew the results. The babies were then evaluated periodically, beginning at six months and then every six or 12 months on through young adulthood. Their mothers agreed to be tested for drug use throughout the study. Attrition cut the final longitudinal sample by half.

Because of the decision to not study premature babies, there may be a slight under-estimate of cocaine effects, since one of the consequences is premature birth and low birth weight. 224 is a respectable sample for a clinical study, though rather small for more detailed analysis of confounding effects. As we have so often lamented, humans are a nuisance to study. People who take one drug also tend to take other drugs, including alcohol, and are less respectful of their health generally, less able to get and keep employment, and less able or willing to save money. The confounding effects are the usual mess of multiple possible causes, many self imposed.

On the issue of whether crack cocaine mothers give birth to significantly damaged children, the published work suggests not. Frank et al. reviewed the literature (37 studies) up to 2000 and concluded: “After controlling for confounders, there was no consistent negative association between prenatal cocaine exposure and physical growth, developmental test scores, or receptive or expressive language. Less optimal motor scores have been found up to age 7 months but not thereafter, and may reflect heavy tobacco exposure. No independent cocaine effects have been shown on standardized parent and teacher reports of child behavior scored by accepted criteria. Experimental paradigms and novel statistical manipulations of standard instruments suggest an association between prenatal cocaine exposure and decreased attentiveness and emotional expressivity, as well as differences on neurophysiologic and attentional/affective findings.”

In that review, Frank quotes 5 papers by Hurt:

79. Hurt H, Brodsky NL, Betancourt L, et al. Cocaine-exposed children. J Dev Behav Pediatr.1995;16:29–35. [PubMed]

80. Hurt H, Brodsky NL, Betancourt L, et al. Play behavior in toddlers with in utero cocaine exposure. J Dev Behav Pediatr. 1996;17:373–379. [PubMed]

81. Hurt H, Malmud E, Betancourt L, et al. A prospective evaluation of early language development in children with in utero cocaine exposure and in control subjects. J Pediatr. 1997;130:310–312. [PubMed]

82. Hurt H, Malmud E, Betancourt L, et al. Children with in utero cocaine exposure do not differ from control subjects on intelligence testing. Arch Pediatr Adolesc Med. 1997;151:1237–1241. [PubMed]

83. Hurt H, Malmud E, Braitman LE, et al. Inner-city achievers: who are they? Arch Pediatr Adolesc Med. 1998;152:993–997. [PubMed]

I have looked one other paper in more detail, having come across it in separate searches (it looks pretty similar to no. 82). At age 6 there are no significant differences in Wechsler scores, which are in the low 80s for children and mothers in both groups. I have also contacted Dr Hurt to make sure I have the full list of relevant papers.

It seems that cocaine is no big deal for the developing brain. Brains are often spared dreadful insults, even short famines as in the Dutch hunger winter. Frankly, this feels like a very significant finding. Cocaine does things to the brain of the habitual user, so its inability to affect a vulnerable baby in the womb is very interesting. Is it a vivid example of the environment not have much effect on anything? Or is it just an exception? If a heavy dose of crack cocaine in-utero doesn’t touch you, what is the chance of a rap video doing so?

Now let us turn to poverty:

“Researchers Probe How Poverty Harms Children's Brains” Chronicle of Higher Education, 2008, Vol.54(25)

  • Description: In 1989, Hallam Hurt, a neonatologist in Philadelphia, started recruiting poor inner-city women for a study of how cocaine use during pregnancy affects the developing fetus. Dr Hurt enrolled women who had used cocaine while pregnant and balanced them against a control group of equally poor women who had not taken any drugs. Years later, when the physician conducted follow-up intelligence tests, the results provided a shocking indictment of American society. The tests showed that children exposed to cocaine in the womb had a mean IQ of 79 at age 6, a full standard deviation below the average. Even more disturbing, though, were the results from the control group. The 6-year-olds who had never been exposed to drugs had virtually the same IQ as the children who had endured cocaine running through their veins while inside the womb. Dr. Hurt's data suggests that while cocaine no doubt does cause harm inutero, poverty itself presents an even graver threat to a child's intellectual development. "Growing up poor is bad for your brain" says Martha J. Farah, director of the Center for Cognitive Neuroscience at the University of Pennsylvania, who has collaborated with Dr. Hurt in recent years. What Ms Farah and other researchers are now trying to tease apart is exactly how poverty--which affects 12.8 million people under age 18--takes its toll on the brain. The preliminary results from her studies and others are pointing the way toward methods that might ameliorate some of the effects of poverty.”

What have the authors left out? Well, nearly all their subjects were African Americans. In repeated population surveys their intelligence scores are in the IQ 85-90 range. This sample is no different. Whether the causes are genetic or environmental or some blend of both is not discussed. Indeed, in the subsequent work two issues are underplayed or ignored.

Issue one, as just mentioned, is that African American intelligence and scholastic ability are well behind European American levels, by about 0.6 to 1.0 standard deviations depending on the measure (the Rindermann and Thompson Intelligence paper  is available online, and we believe there was some significant narrowing of the ability gap up to 1989, which stalled until 2000, though we don’t know what caused it).

Issue two is that when you rank people by social class that is not a pure measure, imposed upon helpless citizens by heaven. It is likely to be caused, in part or to a very large degree, by ability and character differences. Hardworking, restrained, future-oriented persons tend to get better jobs, and try to pass on those values to their children, as well as passing on their genes. There seems to be a whole academic industry looking at the effects of SES without looking at intelligence or genetics. I believe that the proper policy should be to let all schools contend, and all hypotheses compete.

Anyway, here is their key paper: “Childhood poverty: Specific associations with neurocognitive development” Brain Research. Volume 1110, Issue 1, 19 September 2006, Pages 166–174

From their crack cocaine sample they pick 30 low socio-economic status children and contrast them with 30 not so low economic status children drawn from the community. Yes, that is right, 60 children in total. On this basis they contrast outcomes, attributing the differences to social class and, thereby, to poverty. They do this on 7 measures of cognition. 30 pairs, 7 measures. They do not report on the means and standard deviations of their tests. They say that they have given the Peabody Picture Vocabulary test, a measure of intelligence. I cannot find the results in the paper. I have asked if there is a technical appendix. The paper seems to be written back to front: findings first, some results next, and then the boring realities last, if mentioned at all.

They do their structured equation modelling on the basis of socio economic status, and do not appear to include intelligence as a variable in the equation. It is well nigh impossible to find their results. They may have done a better paper somewhere else, so I have asked for a complete list.

So, are the reporters and researchers on crack cocaine? I doubt it. They are on stronger stuff. They are on “Selective Attention”. To giver them their due, the researchers seem to have proved one important thing, which is that in-utero exposure to cocaine does not affect intelligence and behaviour. Their sample are virtually all African Americans who also take other drugs, often lead disorganised lives, and end up in poor and dangerous neighbourhoods, where other people take drugs and lead disorganised lives. Researchers and reporters are right to report their findings. Clinical samples tend to be small, and not always representative, but they are perfectly capable of finding valid results.

However, the researcher’s wish to show that all these unfortunate behaviours are caused by poverty requires a larger sample, other methodologies and other control groups of different ethnicities. Vietnamese and Koreans are also often poor when they arrive in the US, but few of them remain entirely so, and few take cocaine. You cannot simply assume that social class is an explanatory variable. Intelligence as a cause of behaviour must have a fair chance of participating in the equation modelling. This is where selective attention to causes is most troublesome. If all you see are social forces imposed on people from outside you will never see the way in which personal choices can lead to unfavourable outcomes. Selective attention prevents a full understanding of what may be happening. 

Disclaimer: This post was written under the influence of coffee. If I get more and better papers out of this research group I will change my views.