The Daily Mail covers Were the Victorians cleverer than us?

http://www.dailymail.co.uk/sciencetech/article-2323944/Were-Victorians-cleverer-Research-indicates-decline-brainpower-reflex-speed.html

The Daily Mail website had 105 million readers in August 2012, This put it in No 1 position, ahead of even the BBC News website. Getting a mention is a guarantee of a large readership in the English speaking globe. The left hand and wider column contains the main news stories, while the narrower right hand column contains the female stories. 

The Woodley et al paper was reported in the main section. In terms of thoroughness, phrases, pictures and column inches, it was superior to The Daily Telegraph. The Daily Mail spoke of REVERSE selection, and gave Darwin, Faraday and Babbage as exemplars of Victorian genius, and in a flash of inspiration illustrated the era's inventiveness with the differential calculating machine, the grandfather of computational devices.

A grand day out for Woodley, te Nijenhuis and Murphy.

Dr Michael Woodley answers questions about the implications of slowing reaction times

http://ruvr.co.uk/2013_05_14/intelligence-IQ-brain-Victorian/

Colonial Literacy, sentence complexity, and present day reading ability

http://www.freakonomics.com/2011/09/01/were-colonial-americans-more-literate-than-americans-today/

Sanjoy Mahajan at freakonomics.com has an interesting piece on Colonial literacy, looking at the success of Tom Paine's 1776 "Common Sense" which in one year was read, or at the very least bought, by 20% of the American colonial population. Translated into today's US population, that is the equivalent of of a book selling 60 million copies. Few books attain that level. It took 8 years for The Davinci Code (a book not about common sense) to reach that level.

Although the words are short, the language and reasoning of Common Sense is rich and complex. Here is a very small example:

Society in every state is a blessing, but government even in its best state is but a necessary evil; in its worst state an intolerable one; for when we suffer, or are exposed to the same miseries By a Government, which we might expect in a country Without Government, our calamity is heightened by reflecting that we furnish the means by which we suffer.

You may be a different case, but I did a double-take or two, to make sure I was carrying the sense well enough to go on the the concluding punch line. Such complexity is at the heart of reading for meaning. The current National Assessment of Adult Literacy classifies the above text as being at the highest level, Proficient Reading, only attained nowadays by 13% of the American population. 

So, despite the apparent rise in intelligence suggested by the Flynn Effect, proficient reading has fallen from an implied 20% to a measured 13%, using comparable measures of complexity.

Mind you, 1776 was something of a special year for Americans, one which encouraged serious reading. They may have made a particular effort to understand the text. Either that or they read proficiently, inwardly digested, and came to their own proficient conclusions. Paine's view was clear: "To have had a part in two revolutions is to have lived to some purpose."

Regard him as one of the early bloggers.

The Dismal and Sloppy Manual of Madness

The Diagnostic and Statistical Manual is neither diagnostic nor statistical, but it is a godsend to any insurance-based health system, because every patient must have a diagnostic number before they can claim their money back, and every diagnosis requires a medicine, which makes the manual attractive to pharmacological companies. The recent controversy about the 5^th revision is in some ways a compliment, because it shows that it has established itself as a major reference work.

The problem is that the manual has always been a muddle of conflicting opinions, often ill at ease with itself. It is not based on a statistical approach to mental health problems arising from a proper epidemiological population study, but rather to a committee-based discussion about the common constellations of problems encountered by psychiatrists in clinical practice. Because psychiatrists cannot always agree, the manual follows a pick-and-mix approach to diagnosis, in which all you need to have is 1 or 2 symptoms out of 4 or 5 in each category, such that patients can attain the diagnosis with a very different pattern of symptoms.  In line with American productivity, the list has expanded generously from one edition to the next, (see Icebergs and Onions) as if madness were increasing, a sort of Flynn Effect of lunacy.

It is not all rubbish, because psychiatrists can notice patterns like any other professionals, but it tends to generate many over-lapping descriptions, and a proliferation of categories, sometimes under pressure from patient groups, who see the whole exercise as a matter of obtaining legitimacy, whilst others campaign to have themselves removed from the list, such as homosexuals who do not see that their sexual preferences constitute a disorder.  

Knowing that they would not be able to agree on a common theory, the participant psychiatrists have ended up as butterfly collectors exhibiting an assembly of brightly coloured disorders, each with a proud catalogue number. One particularly gaudy specimen is “disorders not otherwise specified”, a rather common Lepidoptera, it would seem.

How should a psychiatric/psychological disorder be defined? Four tests provide a useful start.

1          The diagnosis should have internal coherence, with the relevant symptoms having positive predictive value one to the other. Each symptom should be more strongly correlated with the other symptoms in the diagnosis than they are usually correlated with other extraneous problems. One positive symptom should predict the other positive symptoms, such that they all occur together more frequently than in other disorders.  (In statistically terms, there must be high correlations between most of the symptoms, such that you could get a high R squared in a multiple regression equation).

2          The diagnosis should be distinct from other groupings, with minimal overlap. Some aspects such as depression or anxiety will be very common, but there must be something distinctive if the disorder is to have a separate category name.  (In statistical terms they should be distinct using cluster analysis, or discriminant function analysis, all of which should be apparent using old-fashioned t tests between the group symptom totals).

3          Ideally, there should be some therapeutic or research advantage to the classification. In the absence of clear biological indicators, diagnostic categories have to be provisional, but they can often be clinically useful.  (In statistical terms the diagnoses must predict different outcomes and responses to treatment, and reduce errors of prediction as regards outcomes).

4          It should not be an arbitrary sub-set which leads to tautological self-confirmations. By cherry picking your cases you can create many apparent syndromes. For example, by studying only those cases of autism in which the parents believe that the condition was brought about by a vaccination, you can quickly gather suggestive data implying that there is a syndrome of vaccine damaged children with resultant autism. (In statistical terms the samples have to be drawn randomly from the population and the symptoms and putative causes must be considered objectively for cases and non-cases).

Here is a list of generic problems with DSM which I produced some years ago:

1.      Neither diagnostic nor statistical, just a stamp collection

2.      No cluster analysis, so disorders are poorly differentiated and poorly supported

3.      Does not give statistics of symptom frequency for each diagnosis

4.      Categorical, not dimensional, which is against the evidence.

5.      Too many disorders, many of them overlapping

6.      Diagnostic categories are over-inclusive and pathologize ordinary life

7.      Not purely scientific, but manipulated by interest groups

We are now awaiting the 5^th edition of DSM. The British Psychological Society has got its retaliation in first http://apps.bps.org.uk/_publicationfiles/consultation-responses/DSM-5%202012%20-%20BPS%20response.pdf

My own view is that the proper way to look at psychological problems is to study the mental health of entire populations. When you do that you usually find dimensions rather than categories. Take depression. Most people have low mood sometimes. Some people have low mood more frequently. A minority have episodes of extremely low mood, and at those times are very vulnerable, and at risk of self-harm.  Psychologists (and quite a number of psychiatrists) prefer the dimensional approach. They argue that there are no common disorders, only extremes of quantitative traits.

However, although the dimensional approach makes most sense most of the time, some conditions may well represent a discontinuity. For example, all of us may feel suspicious about how we are being treated from time to time (particularly within large institutions) and this might seem no more than understandable mild paranoia. Not every promotion is achieved by the best candidate. Suspicion is natural, and sometimes justified. Yet the level of suspicion in severe paranoia is of a different order of magnitude. It corrodes the sufferer’s ability to live a productive life. Perhaps there is a real paradigm shift in such cases. The category of paranoid schizophrenia may stand up as a category. It is very different, and different from the shades of depression and anxiety which commonly affect most people.

At a more basic level, it would be good to have some theoretical basis for diagnosing mental disorders. A diagnosis of schizophrenia usually is associated with a sharply reduced level of contribution to society, and a fourfold increase in violence. A diagnosis of anorexia nervosa is associated with increased mortality, with about 10% of sufferers dying young.  Depression and anxiety at the extreme levels of the trait are very handicapping, and severe depression is associated with suicide. Homosexuality is not currently a diagnosis, but it is associated with sharply reduced fertility. Which, if any of these outcomes, makes us feel that something has gone very wrong with the person in some important regard?

In the meantime, it is very likely that your own personal problem has a number, and that the latest edition has been written purely to classify you.  The tablets are in the post.

The Telegraph covers the Victorians were smarter than us story

http://www.telegraph.co.uk/science/science-news/10053977/The-Victorians-were-smarter-than-us-study-suggests.html

Psychological Comments broke the story first, but it is good to see main stream media covering intelligence research, in a brief but accurate piece.

Cleveland slaves and dreams of freedom

In its kindly role as an educator, the BBC have provided a map of Cleveland, Ohio, USA showing where the poor unfortunate women Gena DeJesus, Michelle Knight and Amanda Berry were abducted, and the house some distance away in which they were found captive.They were held in that particular house for the 10 years of their imprisonment, so a few points are apparent.

All three were taken from street corners on Lorain Avenue, within a very short distance of each other.  A current description of that avenue is as follows: “Once an early stagecoach route, Lorain Avenue is now an eclectic mix of specialty shops, ethnic markets and eateries, delis and fine dining restaurants, Irish pubs, antiques and flea markets, entertainment spots, spectacular architecture, historic and sacred landmarks. Lorain Avenue's diversity beckons all. Whether a tourist from out-of-town or a neighbor from around the corner, Lorain Avenue is a destination for the urban explorer. There is plenty to see, do and appreciate.”

This suggests that, unless there has been a big change over the last decade, at the time of the abductions it was already a shopping and partying part of town, with some unaccompanied women likely to be present in a mix of strangers and “urban explorers”, many of them in cars.  Cities have places where people are known, and areas where nobody is known, which is one of the mains points of a city. The area is a crime hotspot, though hardly outstandingly so in Cleveland.

Driving directly along Lorain Avenue up to the centre of town takes you under a freeway and then, one turn south down Fulton Road leads directly to the address of the domestic prison at Seymour Avenue. It is a simple drive, yet it must feel miles away, rather than just the 3 miles or so as the crow flies.

Predators have one major difficulty to overcome: they are most likely to be caught if they commit their crimes right on their doorstep.  So, they maintain the cover of the Good Person, known in the neighbourhood to be above suspicion, in the way that most people are judged above suspicion on the grounds of their ordinariness.  Predators tend to hunt elsewhere, where they are not known at all. Their judgement as to what constitutes “elsewhere” is often very lazy. A large road or a railway line is enough to define the Home versus Hunting Ground boundary.  In the case of a driver going from Lorain Avenue back to Seymour Avenue there is indeed also a major railway line to cross, in fact two of them, and you have to cross the freeway again. Although there are more direct routes, it may be that the kidnapper conceived of himself as being very far away from where he captured his victims, because there appeared to be three barriers between him and his crimes.

These patterns are of some help to the Police, though only in very general terms. David Canter at Huddersfield University has done lots of work on the geography of criminality. His book "Criminal Shadows" explains some of the things that can be learned from the location and timing of crimes, and how modern investigators look at surrounding areas in the hope of narrowing down the places they need to search.

Police are often castigated when perpetrators are found “only a few miles away” from where the crime was committed, as if mere Euclidian distance were enough, rather than population density. There are many of these clapboard houses in the city, every one like every other one, filled with people wearing similar clothes and eating similar food.

Cleveland is the 11^th most dangerous city in America.  The data for 2011 show the following figures, all given as the rate per 100,000 population so to get the totals you should multiply by 4: murders 74 (UK rate about 1.4); rapes 354; robberies 3,156; assaults 1,842; burglaries 10,706; thefts 10,524; auto thefts 4,093; arson 319. Any police force faced with this crime rate will have difficulty solving cases.

The racial makeup of the city in 2010 was 37% White, 53% African American, 10% Hispanic and 1.8% Asian, plus others.  Policing cities with different racial groups living in separate neighbourhoods is usually a bit more difficult, because it is harder to gain trust, and to show that all groups are being protected equally. Also, groups vary in their willingness to report crimes to the Police, particularly if the cultural norm is to distrust and avoid them.

I can recall one young woman in London saying to me, after being held hostage and abused for a shorter but terrifying period of time, that her community and some of her family still objected to her having “snitched” to the Police about her ordeal.

It is part of every reader’s desire to want the victims released from the agony of their satanic prison. Why did the Police not find them? The Police have checked their records, claiming they received no reports about the prisoners in the house. These claims and the relevant police records ought to be inspected. However, the context in which the Police work should also be inspected. They have many crimes to investigate. Yes, they must keep searching for all missing persons, but the usual pattern of events is that after weeks have passed they know they are likely to be searching for dead bodies. Cleveland aside, detection rates in every country are often low, though the rates are higher for murders. It is relatively easy to keep prisoners in basements and attics, and this has happened in quiet suburban streets in towns where crime is very rare.

The worst thing about these Cleveland crimes is that for all those years the victims were but one step from freedom, metaphorically living next to us, but in a private hell, dreaming of the freedom which is now theirs.

Jason Richwine and a bottle of Rich Wine

 One of the pleasures of taking a break in France is that when you “French Google” (an enquiry after meaning, not a sexual position) the case of Jason Richwine, currently subject to a public hate session, you get a reassuring collection of articles on fine wines. But, away from la belle France, in the land of Coca Cola the name of Richwine is now up in the spotlight of the haters, being Watson’d (see James Watson, Nobel Laureate and UnPerson on this blog) for repeating out loud the well-known data on intelligence, scholastic achievement and employability which is normally published in discrete tables in obscure papers, where it will not frighten the horses.

Although our genetics we will always have with us, the code of our ancestry written in every cell of our bodies, the labels we attach to racial groups, generally accurately, vary from country to country. The US census lumps together Mexicans, Puerto Ricans and other Spanish speakers, usually calling them Hispanics or Latinos. I can qualify linguistically, if not genetically. Facts on this group can be found from the Census, the National Assessment of Educational Progress, and other official sources. As ever, Steve Sailer has a good set of meta-analyses:

www.isteve.blogspot.com

He identifies one of the largest studies:

http://lesacreduprintemps19.files.wordpress.com/2012/11/ethnic-group-differences-in-cognitive-ability-in-employment.pdf

Heiner Rindermann at the University of Chemnitz, Germany,  is working on the latest NAEP results, in a paper which may be coming out soon in Intelligence, and which is with reviewers at the moment.

I have had a look at what Jason Richwine has said, and his comments are in line with the current data.  So here is the challenge: a bottle of fine French wine sent to the first person who can show that Hispanic/Latino American intelligence and scholastic ability is on the same level as European American intelligence and scholastic ability.

Data please.

Cleveland suspects: Private domestic prisons

It is hard to estimate how many people are being held in private domestic prisons: basements, back rooms, fenced-in tents and huts in back gardens. The main difficulty is that the initial class, missing persons, is very large. Many thousands go missing every year, presumable to run away from disliked parents. Mostly they are teenagers just running away from home. Most of them return, or at least communicate with home later on, but some do not, or not for many years. This is one factor which makes it difficult to find missing persons. The other difficulty, bluntly, is that it is relatively easy to hide prisoners in domestic settings, particularly in places where there are weak community ties. Ties have to be strong enough for neighbours to know exactly who has children or relatives staying with them, and something about the organisation of the household. That is an unusual level of knowledge to find in anonymous suburbs. Further, most wealthy societies have spare rooms, and even small families can buy enough food and clothing for two families without raising any suspicion.

Of course, these terrible cases seem to be very rare, but given the above circumstances it could be that it is only their detection which is very rare. Perhaps the best estimate would be to guess what fraction of children who are still missing after a year have been murdered (probably lower than 1%) and then what percentage are captive (an even lower percentage, I would imagine, but on no very solid grounds other than perpetrator's fear of being found out might be greater than the benefits of keeping slaves).

By the way, the press often ask: what is it about Cleveland, Austria, Gloucester etc which has allowed these crimes to happen? Nothing. Most people live in suburbs, don't know everything about their neighbours, don't think anything awful is happening in their street, and are usually right.

Fat is an intellectual issue

As a general rule, social scientists should be restricted to three factors, and allowed to deal with four factors only when they have achieved public renown. In my own case, I try to restrict myself to two, because holding two ideas in mind is hard for a psychologist.

It is clear, from both epidemiology and casual observation of the British street scene, that Britons are getting fatter. The great fatness that was visible in the US has now spread here. Clearly, this has a simple, one factor explanation: people are eating more. A cursory look at human metabolism shows that a small amount of food goes a long way, unless you are doing heavy manual labour, where a moderate amount of food goes a long way. Replacing the calories expended by exercise takes about one minute. I can be precise about that. Yesterday my 600 meter, 23 minute morning swim used up 175 calories (and my exercise watch is probably being generous). My usual yoghurt contains 154 calories. Croissants? Why should I touch those? I am told that an almond croissant contains 504 calories, but that need not concern us here. Assuming normal exercise during the rest of the day, the maximum I will need is 2,500 calories. Yes, no more than 5 almond croissants, but let us drop the subject.

Let us search for the second factor. Why is it that some people are fatter than others? At this stage the “multifactorial” gang make their entrance: glands, genetics, advertising, international food businesses, supermarket display shelves, television ads, leisure, lack of local sports facilities, and a profound crisis of capitalism/consumerism/spiritual values. I agree to all of the above, but what I am asking for is a predictive variable measured when children were young, and then evaluated against fatness in middle age.

Such a second factor has been identified by Kanazawa (2013). http://personal.lse.ac.uk/kanazawa/pdfs/O2013.pdf  He has used a famous population sample: all those babies (n= 17,419) born in England, Wales, and Scotland during 1 week (03-09 March 1958).  This is a proper sample: none of your convenience sample of n=30 sort of rubbish. Kanazawa had been surprised that other researchers had argued that, once you corrected for education, there was no link between intelligence and subsequent obesity. It turns out that this finding is based on partial use of the intelligence data. He found that if you include the full set of intelligence tests at 7, 11, and 16, and measure weight at 51 years of age (oh, the power of population samples) then there is a strong relationship, such that even intelligence at 7 predicts weight at 51.

In a very interesting twist, the effect of intelligence on weight only becomes apparent when children leave home, and can control what they eat. It is the opposite of all the “you are conditioned by your family environment” theories. Freedom of choice leads to different life styles, mediated by intelligence.

At this stage you may wish to stop reading, because I have just shown you evidence that intelligence at age 7 predicts obesity at age 51, QED. Stay with me a while. Parental BMI also has an influence. Fatter parents have fatter children. How does one explain that? Is it that children ape their parents through some cultural modelling? Probably not, because as we have just learned, the effect happens long after children leave home. It may be that parents with low IQ are themselves more likely to grow up to be fat, and that they have passed on the genes for low intelligence to their children. Obesity is just a side effect. It’s that pesky problem of collinearity again, and again. Are children inheriting genes for intelligence or genes for obesity, or both? A proper genetic study (of the sort which has not really been possible until now) might elucidate the causal pathway. Furthermore, although the picture is clear, the IQ/obesity link is not all that strong, and other factors also have an influence. Perhaps, after a genome wide study, we can identify the three or perhaps even four factors which account for most of the variance.

In fact, the whole issue is almost as much of an intellectual challenge as to whether one should eat an almond croissant.

Flynn effect raises all boats, but some are leaky

Woodley, te Ninjehuis and Murphy (2013) have put together an interesting paper. In looking for the Flynn effect they have eschewed intelligence test data, and instead gone for simple, old-fashioned (1884) simple reaction times. This is about the most basic thing you can measure in the nervous system: a signal is presented and the organism responds. It is a crude measure of whether the organism can sense and respond to its environment, and how long it takes to do so.

Much has been made of more complex measures. For example, the complexity of the signal has an impact on response times. It is easier to respond to one light on its own than to watch out for one of two lights, even if they are relatively close to each other, because having to monitor two potential sources of signals imposes a slight load on the nervous system. If you make the task even more complex by requiring responses to patterns of five lights, then reaction times slow even further, following Hick’s Law (that the slope of reaction times will follow a binary choice log₂ function of the number of choices).  

Other sophisticated variations are to distinguish between movement time (taken up by moving your arm) and decision time (time spent looking at the shining light and working out that it is now time to respond).

Simple reaction times are back in fashion. Among other things, they are good at predicting lifespans. See “Can I have a reaction” in order to test your own reaction times, and guess at your lifespan, though we need to go to another data set from Ian Deary for that.

By way of background, both intelligence and reaction speed are heritable at 0.58 and have a correlation with each other of about 0.31. If one corrects for restriction in age range and for lack of reliability the measure probably account for half of the variance in intelligence.  This paper suggests that something seems to be slowing us up. If the Flynn effect is absolutely real, then that should not be the case. We should be super-fast at simple reaction times.

Woodley, te Nijenhuis and Murphy  have conducted a meta-analysis of 14 studies involving Western subjects from 1884 to 2004, which provides them with 16 data points with which to draw the linear regression function showing increased reaction times over 120 years. Interpreting the cause is a different matter. It is possible, but unlikely, that we have been poisoned by some neuro-toxin which is making us sluggish: lead, perhaps. However, lifespans are going up in most of the world, and certainly steadily up in the rich West. Also, lead does not have its main effects on measures of general intelligence. Another possibility is that many people who in earlier eras would have died have now survived their illnesses because of modern medicine, but survive with sluggish reactions. The last option considered by the authors is increasing mutation load, perhaps reducing myelination of neurones, with a consequent reduction in the efficiency of signal transmission and information processing in the brain.

It is possible that at least two contradictory factors are at play here: a welcome general increase in living standards, with much better access to food, housing, health and education boosting intelligence on the one hand; and on the other hand a smaller but persistent increase in mutational load with deleterious intellectual effects, thus cancelling some of the gains. (The rising tide of the Flynn effect raises all boats, but many of those boats are leaky).  If the latter is true, then it ought to be possible to find further evidence to support the hypothesis.  Disentangling the Flynn effect from the Woodley effect will be difficult, but also very illuminating, because we will learn much about the future of human intelligence.

Please cite this article as: Woodley,M.A., et al.,Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time, Intelligence (2013), http://dx.doi.org/10.1016/j.intell.2013.04.006