Milometer event 100,001

 

Returning from dinner at midnight, I decided to check my page view counter, behaviour which constitutes a nervous tick among bloggers. A clear case of operant conditioning. I have got to 100,000 readers. My thanks to all of you.

Pageviews today                              7

Pageviews yesterday                   430

Pageviews last month            14,573

Pageviews all time history   100,001

Entertainingly, the precise midnight result is also a Capicúa or palindrome. Such a number was prized in my youth when it came up on Montevideo bus tickets. I can’t recall getting any, or perhaps they simply didn’t excite me. I learned, very much later, that if you gave them to a girl they were very impressed, and understood that you loved them. Who says mathematics has only a pure, cold beauty and nothing warmer underneath?

Genes, false positives and sample sizes

It is a simple rule of thumb in psychology that your sample size should be five times larger than the number of variables studied. Indeed, it is a minimal requirement, though one that is often ignored. A ratio of 5 to 1 gives you a chance of finding a signal amongst the noise, but noise will still get the upper hand all too often.

Problem is, this was not always apparent in the early stages of DNA analysis, which provided as many points of comparison as a drunken surveyor stumbling round Stonehenge at the summer solstice. Nearly 700,000 single-nucleotide polymorphisms (SNPs) and 1 million imputed SNPs can be generated by a modern genome wide analysis. Those are big numbers, particularly when your sample size is 2,329 twelve-year-olds for whom DNA and genome-wide genotyping were available. The South London Plomin gang have had to admit defeat in their attempt to name and celebrate the genes for receptive language. That receptive language (vocabulary, semantics, syntax, and pragmatics) at age 12 is  highly heritable is not in doubt. After all, it is a significant component in intelligence, which is also highly heritable. In the current study, the authors attempted to identify some of the genes responsible for the heritability of receptive language ability using a genome-wide association approach. They found that no SNP associations met the demanding criterion of genome-wide significance when they corrected for multiple testing across the genome ( p < 5 × 10 ⁻⁸). Even the strongest SNP association did not replicate in an additional sample of 2,639 twelve-year-olds.

So, various headlines present themselves: “Receptive language not genetic” seems a clear favourite, with “Geneticists at a loss to explain how we understand language” a close runner. Of course, this overlooks the difference between heritability estimates (which show the extent of the genetic effect without identifying the mechanism) and genomic analysis (which attempts to identify the underlying code).

Of even more interest to science researchers is the following, unremarked, cultural difference. When psychologists publish a finding, they are usually satisfied with describing what they have found in their particular sample. They leave replication to someone else. Geneticists, on the other hand, usually include an attempted replication in the same paper, generally shooting down the original findings “in the sample of discovery”. Perhaps most of psychology is based on false positives derived from over-enthusiastic application of multiple comparisons in “samples of discovery”.

Genome-Wide Association Study of Receptive Language Ability of 12-Year-Olds

Nicole Harlaar; Emma L. Meaburn; Marianna E. Hayiou-Thomas;Oliver S. P. Davis; Sophia Docherty; Ken B. Hanscombe; Claire M. A. Haworth; Thomas S. Price; Maciej Trzaskowski; Philip S. Dale;Robert Plomin

Journal of Speech, Language, and Hearing Research Newly Published on December 23, 2013. doi:10.1044/1092-4388(2013/12-0303)

History: Accepted 22 Apr 2013 , Received 17 Sep 2012 , Revised 18 Feb 2013

http://jslhr.pubs.asha.org/article.aspx?articleid=1809251

The authors conclude that individual differences in receptive language ability in the general population do not reflect common genetic variants that account for more than 3% of the phenotypic variance. (The multiple comparison criterion). They admit that the search for genetic variants associated with language skill will require larger samples and additional methods to identify and functionally characterize the full spectrum of risk variants.

By now you will know my own opinion, which is that psychological research would benefit from collaborative projects which boost representativeness, increase sample size considerably, and utilize a core set of agreed psychological measures. The chance of that happening when the promotion system favours the number of publications is very low: as low as the chance of reliably finding the genes for something in a small sample.

Is the dark side of parenting genetic?

 

In a novel finding, Robert Plomin and colleagues suggest that negative aspects of parenting are more heritable than positive aspects. They call this The Dark Side of parenting. The effect is interesting and subtle: it suggests that whilst parents are generally consistent in their handling of their children, some genetically driven characteristics of their children lead them into more negative parenting styles.

Genetics of Parenting: The Power of the Dark Side
Bonamy R. Oliver, Maciej Trzaskowski, and Robert Plomin
Online First Publication, Developmental Psychology, December 23, 2013. doi: 10.1037/a0035388

http://psycnet.apa.org/psycarticles/2013-44761-001.pdf&uid=2013-44761-001&db=PA

They argue that the “dark” side of genetically driven child characteristics plays a bigger role in eliciting parental negativity than do other child characteristics in
eliciting positivity across feelings and control. For example, parental negativity encompassing hostility and harsh parenting may be more responsive to genetically driven challenging child temperament than positive features such as warmth and calmness are to less challenging traits. In simple terms, even peaceable parents get irritable with difficult children.

Theoretical and empirical perspectives on parenting have remained largely founded in Baumrind’s earlier work on parenting styles, which at its core, focused attention on two key aspects of parenting—responsiveness/warmth and demandingness/
control (Baumrind, 1973). While researchers have distinguished aspects of parenting further, most notably in the area of parental control (e.g., Barber & Harmon, 2002) and have varied in their construct labels, these two broad dimensions have been endorsed through numerous studies that have sought to characterize them
Here, we have conceptualized these parenting dimensions as parental feelings (warmth, closeness, hostility, frustration) and parental control (discipline strategies
such as remaining firm and the use of physical discipline); these dimensions have shown robust modest to moderate associations to children’s outcomes (e.g., Parke & Buriel, 2006).

Reviews of behavioral genetic studies have noted that control aspects of parenting tend to yield low estimates of heritability while parental feelings yield moderate estimates (Kendler & Baker, 2007; Plomin, 1994; Rowe, 1981, 1983). To be clear, in
child-based studies, these findings suggest that genetically influenced child characteristics may be more important for eliciting parental feelings than control. However, research has seldom distinguished between positive and negative parental feelings and particularly between positive and negative control strategies. Blurring
the positive and negative sides of feelings and control may mask important underlying foundations of parenting. Harsh discipline and effective supervision, for example, may not be opposite ends of a single continuum, and neither may hostility and warmth. Thus, we hypothesized that the underlying genetic architecture of these aspects of parenting may also be distinct. Specifically, following existing relevant family research  as well as work outside the field we predicted that negativity would show greater heritability than positivity across parental feelings and control as well as within parental feelings and within control.

The sampling frame for the current study was the Twins Early Development Study (TEDS), a population-based, longitudinal study of twins born in England and Wales in 1994–1996, recruited from U.K. birth records. Participants are somewhat better educated than average, but are otherwise representative of the UK.

The current study included 2,260 twin pairs at age 9 (1,202 MZ and 1,058 DZ; 1,034
boys and 1,226 girls), 3,850 twin pairs at age 12 (2,027 MZ and 1,823 DZ; 1,752 boys and 2,098 girls), and 2,293 twin pairs at age 14 (1,231 MZ and 1,062 DZ; 1,028 boys and 1,265 girls).

We generated eight scales from identical parent-report measures at child ages 9, 12, and 14 years of parental feelings and control. For feelings, we used an adapted short form (seven items) of the Parental Feelings Questionnaire (PFQ; Deater-Deckard, 2000) and for control, a short (four-item) discipline (parenting strategies questionnaire adapted from Deater-Deckard, Dodge, Bates, and Pettit (1998). Two
standard composite measures were created at each age from the PFQ and Discipline questionnaires: Feelings from seven PFQ items, including the three positive (e.g., “I feel close to my child”) and four negative items (e.g., “I feel frustrated by my child”) and Control comprising four discipline items including two positive (e.g., “I am firm and calm with him or her”) and two negative (e.g., “I tell him or her off or shout at him or her”) items.

Although face validity for our scales is reasonable and appropriate for the hypothesis-driven nature of the current report, variable internal consistency for these scales was found, with reliabilities lower for scales with fewer items, as is to be expected.

We found across constructs that negative aspects of parenting are significantly more
heritable than positive aspects, again at all three ages. For example, for negative and positive feelings, negative feelings showed significantly more heritability than positive feelings, with average heritabilities across the three ages of 44% and 26%, respectively; the pattern was similar for parental control, with average heritabilities
across the three ages of 27% and 6% for negative and positive aspects, respectively. Finally, creating scales for all the negativity items and all the positivity items regardless of whether they were on the Feeling or Control scale yielded significantly
greater heritability for the negativity than for the positivity, with average heritabilities across the three ages of 44% and 12%, respectively.

For both feelings and control, negativity consistently yielded significantly higher heritability estimates than did positivity, a finding that held for the overall negativity and positivity latent factors (h2  .42 and .10, respectively).

We argue that the “dark” side of genetically driven child characteristics plays a bigger role in eliciting parental negativity than do other child characteristics in eliciting positivity across feelings and control. For example, parental negativity encompassing hostility and harsh parenting may be more responsive to genetically driven challenging child temperament than positive features such as warmth and calmness areto less challenging traits. Distinctions of parenting valence seem to be important for understanding family processes.

One caveat is critical here. In categorizing measures of parenting into positive versus negative valence, we do not include maltreatment. That is, the pattern we report includes aspects of harsh discipline, such as yelling and spanking, but not abusive
forms of parenting. In one study that explicitly looked at this distinction, Jaffee et al. (2004) found that while harsh discipline was moderately genetically influenced (25%), physical maltreatment was not (7%). These findings suggest that children’s genetic influences are largely irrelevant for their vulnerability to maltreatment
and that characteristics of the perpetrator are what are important.

So, one might summarise the findings as saying that when parents deviate into yelling and spanking, it is the genetic characteristics of their children which cause them to do so.

Uruguayan cannabis: an export opportunity?

 

A kind school friend (with whom I did not smoke dope, mostly because she and I were 10 years old at the time) has sent me a newspaper article from El Pais about the interest engendered by the Uruguayan cannabis experiment. As readers of this blog will know, nothing, but absolutely nothing, not even the desperate desire for instant gratification, speeds up the slow process of the local legislative and bureaucratic deliberations. It will be another four months of deep deliberation, assisted by copious quantities of whisky before the weed is made available, at a cost of 0.7 Euros per gram. That is precisely the same as  the current black market street cost. No fools, these legislators. They know they are taking a gamble, but since all other countries have failed to reduce actual cannabis use, they may be on to a winner. They assume that the consumers will prefer a quality assured product, and that the income stream to criminal gangs will be reduced. Perhaps.

However, in an unexpected twist, a new stream of dope heads has opened up: governments. Canada, Israel and Chile have been in talks with local officials about buying large quantities of weed for their own, entirely legal, approved users of medicinal cannabis, as part of pain control for chronic conditions.There is talk of vast laboratories, and government cannabis farms.

So, to the export benefits of beef, lamb, rice, soya bean, tourism and football players, we will shortly be able to add La Droga Uruguaya.  All of this can only happen once the laws are finally passed. But the legislators are on holiday. Drinking whisky.

 

http://sociedad.elpais.com/sociedad/2014/01/06/actualidad/1389041302_490726.html

Hope, fear and Islamic terrorism in America

 

 

A very loyal reader wonders if the apparent rise in hope and fear in the last decade is really linked to terrorism, noting that no such rise was apparent for the American Civil War, and the First and Second World Wars. Of course, History is not an experimental science. There is always, as Popper observed, a poverty surrounding historicism. Most grand histories are a collection of “just so” stories. I suppose, tentatively, that the impact of the Twin Towers as a historical event was due to the prospect of a vast global religious war, coupled with the far greater impact of modern television coverage: immediate, lurid, all-consuming. Would previous wars have continued for so long with vivid coverage? cf Vietnam.

Nonetheless, there is a sharp rise in hope and fear after 9/11, in synchrony with a sharp rise in terrorism and as part of a rise in Islamic and even a slight rise in Christianity. There is some evidence of concern and distress at a new source of hatred, from which Americans had been sheltered for most of their history. The Saudi attacks were a vivid shock, plunging the American public into horrible lessons in history and geography.

Vast historical texts have been written on such synchronies. Here, we take a more sceptical approach. Slightly different words and other phrases might paint a differnt picture.  For once I will not be asking for more measures, and for larger sample sizes. No replications please.

After 2 centuries, hope and fear get mentioned again

 

 

The clue was in the date. A subtle effect of 9/11. The IRA got the same effect by bombing the Royal Exchange, London, (partly backed by US citizen contributions). Bomb people in Northern Ireland or the Middle East and most readers turn the page. Destroy a big building in a city and governments and citizens pay attention.

Does education always disappoint?

Continuing my quest for good quality, legal, state sponsored and regulated marihuana in Uruguay, I have been gently enquiring whether people have been signing up at the local pharmacy. So far, no one has admitted to doing so. Instead, they gripe that Uruguay is getting known for the wrong reasons.

However, the main lament, said with great passion, is that the education system is broken. The after dinner talk is that children’s vocabularies have shrunk to the basics required for crude communication. I thought it apposite to compare Uruguay with Spain and Italy, from whence most of its citizens originally emigrated. In fact, both those Iberian nations are within measurement error of each other, but both are better than Uruguay.

              Maths     Reading   Science

Italy         485          490         494

Spain       484           488         496

Uruguay 409           411          416

 

In terms of trends, Spain has improved by about 2 points since the last assessment, while Uruguay has lost 1 point in Maths, and 2 in Reading and Science. Uruguay has lots of low achievers in Maths, at twice the OECD average. Something is going wrong in maths teaching. Perhaps the locals are right: an education system which was once respected and even admired has lost its way. 6 million dollars is being spent from tight educational budgets just on security to stop school windows being broken by stone throwers. Respect for teachers is waning. It is a little early to blame the Left leaning government (though many do so) and it could be due to: social media, mobile phones, over-generous social security payments, and a lapse of family and Burgher aspirations. It might even be due to free enterprise marihuana, the state sponsored version being yet to hit the streets.

It is little comfort, but Brazil and Argentina are a worse. Come to think of it, it is a great comfort. Uruguay is ahead of its large, overbearing and dysgenically dull neighbours. Scrap all the above.

Shrinking humane genome?

“The fact that the human genome is so parsimonious raises an interesting question. What exactly is it about the human genome that gives rise to our staggering complexity, in the brain for example, compared to other animals such as monkeys, worms or even water fleas?”

Ref: arxiv.org/abs/1312.7111 : The Shrinking Human Protein Coding Complement: Are There Fewer Than 20,000

Some alarm is being raised by the finding that our genome appears to be smaller than other lowly and less complex organisms. This is a key result from a new attempt to define what constitutes a gene, in terms of whether it encodes detectable proteins, and whether it is similar to genes in other species.

I feel less affronted. Genes have different histories. Some are very cluttered messy codes, others have done well with sparse and elegant solutions. Anyway, perhaps we are reading the wrong end of the Mandelbrot set, and getting confused by the apparent need to match the end product perfectly with the design code.

However, it suggests an interesting possibility: perhaps humans got fast-tracked by some very favourable set of circumstances. Bipedalism? Fortuitous encephalisation? Eating lots of carrion? Getting friendly with the Neanderthals? Flukes happen.

For the New Year: Living in hope and fear

 

You and I know that the end of a year is a milometer event, the mere completion of one solar orbit, the defining point set somewhere in mid-winter in Europe, but at other points elsewhere. It is no achievement on our part, though something of an achievement to have worked out that the solar year repeats itself, and a further achievement to have worked out why in terms of Newtonian physics.

Nonetheless, this is a time for hoping that the next year will be better, suggesting that for some mysterious reason the last year had established some sort of aura or depressive groove which can be reset by the magical change of number. At least the Chinese have a better cover story, naming their years so as to allow citizens to ascribe characteristics to them. So, we hope for better, but fear worse. This is also the time for frightening predictions, about obesity, climate change, and sundry popular worries.

With that in mind, I predicted that hope would always predominate over fear, for the simple reason that reproduction requires optimism. I turned to N gram for confirmation, and found my views substantially confirmed. There was also a surprise: peaking in 1830, hope and fear have since been in free fall. Both words have reduced in frequency over 200 years, and by the Millennium were almost at par. Any reasonable computer model would have predicted fusion, or even a cross-over, with fear in the ascendant. For some reason there has been a rebound. Why?

It has nothing to do with the sin of greed, nor is it anything to do with optimism and pessimism. On this scale they are irrelevant. Neither do boom or bust figure, nor stocks or shares. Not even recession shows an effect.

Perhaps it is simply a song with those words in it, but we have begun to hope and fear again. Perhaps you can suggest why.

PISA goes to US, finds little bang for buck

 

You may remember that I succumbed to PISA fatigue, and called for dedicated souls to help me churn through the remaining volumes. Andrew Sabisky (@AndrewSabisky) has stepped into the breach, so here is his take on Vol 5 in which PISA visits the US.

PISA 2012 Vol 5

America merits its own volume in the PISA reports, probably because its educational establishment is PISA’s largest customer. Education reformers, backed by the Obama administration, even put together their very own “PISA day” (which fell on December 3rd) to analyze (but not celebrate) America’s PISA results (www.pisaday.org). What message, then, did these ardent educationalists hear from PISA? What messages could they have heard, but, for lack of education, did not receive?

PISA 2012 largely focused on mathematics. America ranks 26th out of 34 participating OECD nations, though it does better in reading (17th) and science (21st). 26% of American 15-year-olds do not reach the PISA “level 2” yardstick of basic mathematical proficiency (OECD average 23%), though this figure falls to 16% after removing those students from an immigrant background. The definition of what counts as “an immigrant background” seems to be given nowhere. Just 2% of American students reach the top band (level 6), compared to 3% across the OECD and “up to 31%” in Shanghai.

These are the basic facts of the American PISA scores. It would seem, therefore, that taken as a group, American students are about average compared to those in other OECD nations, perhaps performing slightly worse in some respects. Of course, treating American students as one unitary group may hide significant and important within-group differences. America is a highly diverse nation, both racially and culturally, though PISA rarely allude to this fact. They do, however, note that Blacks and Hispanics are substantially overrepresented in the American population of low-skilled adults, as measured by PISA’s twin brother, the OECD Survey of Adult Skills (PIAAC). Skills, in the world of PISA, are regarded as all-important, though individual and group differences in the capability of learning certain skills are not considered. Steve Sailer has in fact found data dividing American PISA scores by race with enlightening results (http://isteve.blogspot.co.uk/2013/12/pisa-racial-results-for-americans-on.html).

PISA also attempt to establish some rather less basic and more contentious facts. America apparently has fewer “resilient” students than other countries; just 5% compared to an OECD average of 7%, and between 15-20% in Vietnam, Hong Kong, and Shanghai. “Resilient” students are from the bottom quarter of the socioeconomic status scale (relative to their country of assessment), but who perform in the top quarter of students among all participating countries, after adjusting for socioeconomic status (emphasis added). Therefore, to be classed as resilient, a disadvantaged child does not have to actually score in the top quartile across all nations - he can score considerably less well, but PISA will helpfully bump his scores up. The ghost of the sociologist’s fallacy has returned with a vengeance. The possibility that a low percentage of “resilient” students may in fact function as an indicator of societal meritocracy is also not considered.

Other data, however, perhaps provide more basis for applicable conclusions. The first is that American education is inefficient. Only Norway, Austria, Luxembourg, and Switzerland spend more money per student than America, while nations such as the Slovak Republic spend less than half as much per student as America for the same PISA scores, while Korea also spends considerably less for chart-topping results. Perhaps American educators could safely return some of their budget to the taxpayer and the Gates Foundation, without fear of any loss of performance. There is a statistical relationship between mathematics performance in PISA and national spending on education (r squared = 0.3), though this may be accounted for by the relationship between national IQs and GDP. Cleverer nations, likely to perform better in maths, are also often the wealthier nations on account of their brighter, more productive citizens, and hence have more cash to spend on social goods such as education. PISA, is it worth pointing out, do not follow this line of analysis. America notably spends a higher percentage of its educational budget on “capital outlays” than its competitors (11.4% versus 8.7% OECD average). Perhaps the cash allocated to new school buildings, swanky sports fields, and iPads for all pupils in Los Angeles could be better spent elsewhere.

Does the school climate make a difference? American students are inclined to play truant: 20% have done so within the past two weeks, compared to an OECD average of 15%, and an average of under 5% in many Asian and some European nations. Do American students lack the foresight to make rational decisions in this matter? Perhaps some calculate they can learn more elsewhere? Perhaps some do so accurately. Nevertheless, despite their higher rates of truancy and lower performance, American students do not view their teachers in such a ghastly light; in fact, they view them rather positively, more so than in other OECD nations. 86% of American students think that their teachers are interested in their wellbeing, whereas just 59% of Japanese students do (OECD average 77%). American students also think highly of other aspects of their relationship with their teachers, such as the teachers’ ability to listen and willingness to give their students extra help. The cause of American underperformance cannot seem to be located here. American discipline also seems to be at least on par with the OECD average: 82% of American students report that classroom disruption so severe they cannot work never happens, or almost never happens, compared to an OECD average of 78%. School principals, however, are apparently less sanguine than students about American discipline, though the exact figures are for now lost to PISA’s endless appendices. Overall, the schools with the worst discipline tended to be those with the poorest pupils and the lowest scores, but the nation-level figures perhaps imply here that correlation does not lead us down the path of causation.

School governance is another hot-button topic in nations on both sides of the Atlantic, and here too PISA has some data for policymakers. School autonomy in resource allocation, curricula creation, and assessments apparently correlate positively with higher scores. This relationship persists after controlling for national income, though a correlation coefficient does not appear anywhere. Of course this finding is interpretable in many ways. School autonomy may lead to better results, or more intelligent teachers may demand and receive more freedom from state interference to educate their more intelligent students as they see fit. The usual non-relationship is found (after removing two outliers) between class size and test performance, though Asian nations typically do pay their high school teachers better than America does, whilst also trending towards larger class sizes.

The report also contains a chunky section entitled “Strengths and Weaknesses of American Students in Mathematics”. It runs to 30 pages of A4, but the substance of it is that American students do much worse (relative to Asian and other better-performing nations) on the harder, more cognitively complex PISA items, and do less badly on the easier items. One could interpret this as signifying that some significant amount of the difference between America and the nations that outperform it may be on psychometric g. PISA themselves, however, limit their conclusions to “the relative strengths of the United States lie mostly in the easy items” and “the United States has a particular weakness in the most challenging items”. This is a frustrating failure of analysis just as PISA’s data start to suggest an intriguing pattern worthy of further thought. It is hard to believe that none of the authors of the report had any kind of background in test design.

Lastly, the report attempts to analyze whether or not implementation of the Obama administration’s new “Common Core” universal standards will improve American performance in PISA mathematics. Purely in terms of test readiness, they may indeed do so to a small extent, since the Common Core standards have apparently been heavily drawn from those of PISA. Of course, this assumes the standards are implemented faithfully and without wavering if and when grades begin rapidly to deflate in the face of tougher exams. Experience would perhaps suggest that this is unlikely to occur. We shall see.

Despite its many inadequacies, including a complete failure to include genetic quality (intelligence A) as a variable contributing to both school outcomes and socioeconomic status, the PISA report on American education does retain some value. Most notably it highlights the high rate of financial waste for mediocre results, something the American taxpayer will be displeased to learn. The largely positive atmosphere in American schools does not seem to have much effect on outcomes. For both education reformers and anti-reformers alike, there is much to learn as they fight their never-ending war over the future of schooling in the world’s great power.