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Blade Runner had an impact on me, both as a film and because it was an introduction to the writings of Philip K Dick, whose whimsical work was based on wondering what it meant to be human. Are we as individuals merely constructions of fundamental genetic coding mechanisms, which create treasured but probably false memories of childhood and delusions of uniqueness which give us a sense of identity, but which serve no purpose other than to keep us going, as our genes require? Dick’s speculative hunt for fake humans cast the Turing test in a new light: not as a proof of the ability of artificial intelligence to “pass for human”, but as a test of humanity itself, which leads to a most severe demotion for those who fail to convince interlocutors that they are really human. All that aside, I revere him for his aphorism: Reality is that which, when you stop believing in it, doesn’t go away.
Here, I intend not to track down and destroy errant replicants, but to champion findings which, even if you don’t believe in them, don’t go away.
My text is the recent paper by Plomin, DeFries, Knopik and Neiderhiser “Top 10 Replicated Findings From Behavioral Genetics. Perspectives on Psychological Science” 2016, Vol. 11(1) 3–23. The deeper background is the major textbook in the field by those same authors 2013 Behavioral genetics (6th ed.). New York, NY: Worth.
http://www.gwern.net/docs/genetics/2016-plomin.pdf
By the way, 6 editions should give pause, should it not, to those who just want to jump into the field without doing any of the reading. Below I list, in very abbreviated form, and largely based on the text with a few additions and simplifications, 10 genetic findings which replicate:
1. All psychological traits show significant and substantial genetic influence
For example, a review of the world’s literature on intelligence that included 10,000 pairs of twins showed identical twins to be significantly more similar than fraternal twins (twin correlations of about .85 and .60, respectively), with corroborating results from family and adoption studies, implying significant genetic influence.
For example, for psychopathology a meta-analysis of 14 twin studies of schizophrenia showed monozygotic (MZ) concordances of about 50% and dizygotic (DZ) concordances of about 15%, suggesting significant genetic influence; this finding has been corroborated in more recent studies, as well as in adoption studies.
For personality, scores of twin studies over the decades have shown evidence of significant genetic influence for dozens of traits studied using self-report questionnaires; results have been confirmed in meta-analyses with adoption and family data as well as twin data on 24,000 pairs of twins. Traits such as political beliefs, religiosity, altruism, and food preferences also have shown significant genetic influence. A recent meta-analysis of data drawn from 3,000 publications on nearly 18,000 traits of 15 million twin pairs showed that this finding is not limited to psychological traits.
For general intelligence, heritability estimates are typically about 50% in meta-analyses of older family, twin, and adoption studies as well as newer twin studies. For personality, heritability estimates are usually between 30% and 50%. For example, well-being is a relative newcomer in relation to genetic analyses of personality; a meta-analytic review of 10 studies based on 56,000 individuals yielded a heritability estimate of 36%.
In sum, all traits are genetically influenced.
2. No traits are 100% heritable
Some traits, such as individual differences in height, yield heritability as high as 90%. Behavioural traits are less reliably measured than physical traits such as height, and error of measurement contributes to nonheritable variance. Many have noted that no traits are 100% heritable.
Although this finding might seem obvious and unsurprising, it is crucial because it provides the strongest available evidence for the importance of environmental influence after controlling for genetic influence. Because genetic influence is significant and substantial, one must control for genetic influence when investigating environmental influence. Environmental research using genetically sensitive designs has led to three of the most important discoveries about the way the environment affects behavioural development, presented as Findings 7, 8, and 9.
The environment, broadly defined, has an impact on traits.
3. Heritability is caused by many genes of small effect
If only a few genes were responsible for the heritability of a trait, selected lines would separate after a few generations and would not diverge any further in later generations. In contrast, selection studies of complex traits show a linear response to selection even after dozens of generations of selection, as seen, for example (Fig. 1), in one of the largest and longest selection studies of behaviour that included replicate selected and control lines (DeFries, Gervais, & Thomas, 1978).
It is a pity this figure is not in colour, but the findings are a brilliant example of the breeder’s equation in action (R = h2 S. R is the response to selection, S is the selection differential, and h2 is the narrow-sense heritability.)
The top lines are those mouse strains selected for high activity even in stressful situations, which constitute fearless explorers (non-reactives) while the bottom lines are fearful mice, rooted to the spot in stressful settings (reactives) and shitting frequently. (One of my colleagues, the late Gudrun Sartory, charged with counting the boluses of faeces emitted by such mice, posed a methodological dilemma over a tea break in the Institute of Psychiatry canteen: one terrified mouse had eaten a bolus in panic. Should she count, as required by the test protocol, only the boluses at the end of the experiment, or add the eaten one to the final total?)
Without any form of selection, the middle lines reveal average levels of fear. The difference between the fearless and fearful strains is evident after 7 generations and undeniable after 10 generations. It is selective breeding imposed from outside the population which has caused this massive difference over time, with clear implications for humans under strong selection for any particular heritable characteristic, who might be expected to be very different after 10 generations, say 250 years.
Another overlooked point from selection studies is that genetic effects transmitted from parents to offspring can be due only to additive genetic effects (the independent effects of alleles and loci that “add up”) in contrast to non-additive genetic effects in which the effects of alleles and loci interact. This is important information because it would be difficult to identify specific DNA differences responsible for heritability if genetic effects on behavior were caused by interactions among many loci (epistasis).
In sum, even if you don’t know which genes are involved, by keeping selecting for particular behaviours like intelligence and diligence you can shape the next generations.
4. Phenotypic correlations between psychological traits show significant and substantial genetic mediation
Phenotypic covariance between traits is significantly and substantially caused by genetic covariance, not just environmentally driven covariance. That is to say, taking genetics into account shows that many traits share genetic pathways.
More than 100 twin studies have addressed the key question of co-morbidity in psychopathology (having more than one diagnosed disorder), and this body of research also consistently shows substantial genetic overlap between common disorders in children and in adults. For example, a review of 23 twin studies and 12 family studies confirmed that anxiety and depression are correlated entirely for genetic reasons. In other words, the same genes affect both disorders, meaning that from a genetic perspective they are the same disorder.
The genetic structure of psychopathology does not map neatly onto current diagnostic classifications. Moreover, correlations between personality dimensions and psychopathological diagnoses also are mediated genetically, most notably between neuroticism and depression.
Psychiatry will have to do some re-writing, clinical psychology as well.
5. The heritability of intelligence increases throughout development
This is a strange and counter-intuitive finding: one would expect the effects of learning to accumulate with experience, increasing the strength of the environmental factor, but the opposite is true.
Shared environmental effects, as from family life and school, decrease with age. Good family lives and good schools are not the essential start in life that many people have always imagined, or at least not crucial in societies where family life and schools are reasonably good.
6. Age-to-age stability is mainly due to genetics
Longitudinal genetic studies consistently show that phenotypic correlations from age to age are largely due to genetic stability. In other words, genetic effects contribute to continuity (the same genes affect the trait across age), whereas age-to-age change is primarily the provenance of environmental factors.
For intelligence, similar results have been found, for example, in a meta-analysis of 15 longitudinal studies. This finding creates an apparent paradox: How can the heritability of intelligence increase so substantially throughout development if genetic effects are stable? How can the same genes largely affect intelligence across the life course and yet account for more variance as time goes by? Increasing heritability despite genetic stability implies some contribution from what has been called genetic amplification (Plomin & DeFries, 1985). In other words, genetic nudges early in development are magnified as time goes by, increasing heritability, but the same genetic propensities continue to affect behavior throughout the life course.
This amplification model has recently been supported in a meta-analysis of 11,500 twin and sibling pairs with longitudinal data on intelligence, which showed that a genetic amplification model fit the data better than a model in which new genetic influences arise across time. Genotype/environment correlation seems the most likely explanation, in which small genetic differences are amplified as children select, modify, and create environments correlated with their genetic propensities.
7. Most measures of the “environment” show significant genetic influence
Although it might seem a peculiar thing to do, measures of the environment widely used in psychological science—such as parenting, social support, and life events—can be treated as dependent measures in genetic analyses.
If they are truly measures of the environment, they should not show genetic influence. To the contrary, a review of the first 18 studies in which environmental measures were used as dependent measures in genetically sensitive designs and found evidence for genetic influence for these measures of the environment. Significant genetic influence was found for objective measures such as videotaped observations of parenting as well as self-report measures of parenting, social support, and life events. How can measures of the environment show genetic influence?
The reason appears to be that such measures do not assess the environment independent of the person. As noted earlier, humans select, modify, and create environments correlated with their genetic behavioral propensities such as personality and psychopathology. For example, in studies of twin children, parenting has been found to reflect genetic differences in children’s characteristics such as personality and psychopathology.
In sum, environments are partly genetically-influenced niches.
8. Most associations between environmental measures and psychological traits are significantly mediated genetically
For example, rather than assuming that correlations between parenting and children’s behavior are caused by the environmental effect of parenting on children’s behavior, one should consider the possibility that the correlation is in part due to genetic factors that influence both parenting and children’s behavior. Individual differences in parenting might reflect genetically driven differences in children’s behaviour, or differences in parenting might be due to genetically driven propensities of parents that are inherited directly by their children. For example, for children aged 2 years, the correlation between the Home Observation for Measurement of the Environment was .44 in nonadoptive families, (in which parents shared nature as well as nurture with their offspring), compared with .29 in adoptive families in which parents and offspring were genetically unrelated.
Disentangling genetic and environmental influences on correlations between environmental and behavioral measures is important because 1) if these correlations are mediated genetically, interpretations that assume environmental causation are wrong, with important implications for intervention 2) genetically sensitive designs can identify causal effects of the environment free of genetic confounds 3) genetic mediation of the association between environmental measures and behavioral traits suggests a general way of thinking about how genotypes develop into phenotypes, moving from a passive model of imposed environments to an active model of shaped experiences in which humans select, modify, and create experiences in part based on their genetic propensities.
People to some extent make their own environments.
9. Most environmental effects are not shared by children growing up in the same family
This is an extraordinary finding, and overturns many long-held assumptions. It is reasonable to think that growing up in the same family makes brothers and sisters similar psychologically, which is what developmental theorists from Freud onwards have assumed. However, for most behavioral dimensions and disorders, it is genetics that accounts for similarity among siblings. Although environmental effects have a major impact (see Finding 2), the salient environmental influences do not make siblings growing up in the same family similar. The message is not that family experiences are unimportant but rather that the relevant experiences are specific to each child in the family. This finding was ignored when it was first noted and controversial when it was first highlighted, but it is now widely accepted because it has consistently replicated. The acceptance is so complete that the focus now is on finding any shared environmental influence, for example, for personality and some aspects of childhood psychopathology.
For instance, for antisocial behavior in adolescence, shared environment accounts for about 15% of the total phenotypic variance; however, even here non-shared (unique) environment accounts for more of the variance, about 40% in meta-analyses, although this estimate includes variance due to error of measurement. Academic achievement consistently shows some shared environmental influence, presumably due to the effect of schools, although the effect is surprisingly modest in its magnitude (about 15% for English and 10% for mathematics) given that this result is based on siblings growing up in the same family and being taught in the same school. An interesting developmental exception is that shared environmental influence is found for intelligence up until adolescence and then diminishes as adolescents begin to make their own way in the world, as shown in meta-analyses.
Rather than asking whether a monolithic factor like parental control is primarily responsible for non-shared (unique) effects, it might be necessary to consider many seemingly inconsequential experiences that are tipping points in children’s lives. The gloomy prospect is that these could be idiosyncratic stochastic experiences. However, the basic finding that most environmental effects are not shared by children growing up in the same family remains one of the most far-reaching findings from behavioral genetics. It is important to reiterate that the message is not that family experiences are unimportant, but rather that the salient experiences that affect children’s development are specific to each child in the family, not general to all children in the family.
10. Abnormal is normal
This is an oddly described finding, which simply means that abnormality is the far extreme of a normal behaviour, rarely a discrete entity in its own right.
Quantitative genetic methods suggest that common disorders are the extremes of the same genetic factors responsible for heritability throughout the distribution, although the evidence is indirect and the methods are somewhat abstruse.
Research using the DF method has shown consistently that group heritability is substantial for cognitive disability such as language, mathematical, and general learning disability, as well as for reading disability. An interesting exception involves severe intellectual disability (IQ< 70), which DF extremes analysis suggests is etiologically distinct from the normal distribution of intelligence.
On the basis of common SNPs, it seems safe to hypothesize that most common disorders are at the genetic extreme of the spectrum of normal trait variation. This seems a safe hypothesis because heritability of complex traits and common disorders is caused by many genes of small effect (Finding 3), which implies that together these genetic effects will contribute to a quantitative distribution, as Fisher (1918) assumed, even though each gene is inherited in the discrete manner hypothesized by Mendel (1866).
Here endeth the lesson.
These are not laws, and certainly not commandments, simply findings which are very probably true. Further work will amplify the details. Crucially, we need to understand precisely how many genes of small effect end up having the massive effects we notice in everyday life.
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Was it P.J. O’Rourke who observed that “We slowly turn into our parents?”
No, it was his father.
Excellent article, all things everybody should know, some of which I didn’t know and the rest I had not seen put so clearly and succinctly.
This should be the first article to offer when trying to explain the importance of genetics to those who have always been told that environment is all that matters.
Tell me, doc, does any of this work shed light on Tolstoy’s remark “Happy families are all alike; every unhappy family is unhappy in its own way”?
The graph in finding 3 is both amazing and informative.
I have thought for quite a while now that culture selects its people, and it is notable that Christianity has been extant in Europe for more than 60 generations, and Islam in its region for more than 40 generations. It seems likely that each of those has selected the respective populations.
Probably because unhappiness comes in many forms and variety, and happiness come just from a few things, yeah, unhappy families are different in their problems (but, still problems), but happy ones share the same qualities.
Sorry for the bad grammar.
So when you pick your husband/wife, choose someone who is smart and has the same moral sense that you do, so that you will have children that you can love without pain ?
No, it does not. All families have ancestors.
An aphorism is not upon oath.
It does not have to be true, it just has to sound true.
Searching to make it true, I can think of two possible routes, neither of them anything to do with genetics. One approach is to say that a family will be happy only if it satisfies n requirements, and that even n-1 will cast it into despair. In that sense the happy family will just be happy, the unhappy family will be vexed by the one or many missing ingredients. In that line of argument, everything has to be right before anything can be right.
The other line of argument has nothing to do with families per se. It seems that memory for bad events is better than memory for good events. Presumably, bad events are traumatic and have to be remembered so that they can be avoided in future, for survival’s sake. So, we will have a tendency to unhappiness which will always be linked to a specific event.
“Sorry for the bad grammar.” Not at all; better than my Portuguese grammar, I’ll bet.
Does happiness run in families? If so, how much of it is a genetic trait, how much caused by “environment”?
Presumably this would be a reason for the relative significance of birth order.
Readers see also my:
The Behavioral Genetics Page
This essay is a direct attack against the counter-factual world inhabited by neo-Liberals and Progressives.
For them, there are no such things as race, gender … or genetics for that matter. Indeed, there are no such things as families, societies or nations, just individuals pursuing their private pleasures in a solipsistic world without consequences. All personal choices are equal; all personal traits are fluid. Therefore, by definition, there cannot be any criteria to discern or compare differences in value between anyone’s fluid choices.
If you are a 30-year old cisgendered, 6′ 3″ White male who believes he is a 7-year old Chinese trans female, who is to dispute his choices? If it feels right (for him), it IS right … and it IS real. Otherwise, why would he feel so strongly about it?
To discover that these people want to run governments and school systems (and often succeed in doing so) is scary.
https://www.unz.com/jthompson/genetic-story-jumps-ahead
Also, put “Bad Blood” in the search bar.
Annoying as H3ll, too.
No doubt parasitism has significant genetic components. How do we, as a society, ethically breed those traits out?
Equally crucial, how do we “debreed” (pun intended) gullibility?
This is not very important and it us not about the core value of this article, but Blade Runner is my second best movie of all time, after Terry Gillian’s Brazil (a political satire on the totalitarian society which has already come true). Blade Runner is so special for the reason that you mention in this article – Philip K. Dick examination of what makes us human and if that could be replicated. The screen cap of Rutger Hauer in one of the most striking movie scenes ever still brings the same feeling of wonderment as when I saw this movie the first time. Is it a sense of reality (which does not go away when we stop believing in it), combined with awareness of own mortality which makes us human?
Dr Thompson, a brilliant introduction to an excellent article, thank you.
Not true, but it seems that every happy child got there in his own unique way!
Most interesting article, though there is some jargon that makes me scratch my head. For instance ‘genetic mediation’ and (perhaps shamefully) ‘age-to-age’? Should I just read the Plomin thing?
Regarding 7, 8: Could one say that this is because we are also evolved to raise our offspring in effective, perhaps idiosyncratic, ways?
I am curious how the breeder’s formula is manifested in the Fig.1. How are R, S and h^2 in relation to the abscissa and the ordinate axis of the graph? What does the slope of the curves represent?
Most scientists and academics are just replicators, a life replicating the same boring stuff they learned…
When I saw Terry Gillian’s Brazil in the 1980’s I knew the US was undergoing the Brazilification but in more ways than one: (1) becoming like the dystopian totalitarian Brazil with decrepit infrastructure from the movie and (2) the real Brazil of corrupt police, society stratification, gated communities, shrinking middle class, unresolved race issues… with never ending carnival signifying alleged everlasting freedoms, liberties and happiness.
Yes, best to read the article, but “genetic mediation” means that an association between one behaviour and another, or one behaviour and another factor has some genetic influences in common. So, the genetic factor mediates the relationship between one variable and another.
Regarding 7 and 8, my interpretation is that genetic factors push us in certain directions, such as establishing places to study, habits of learning and so on which have been considered part of the environment (as if they occurred by chance) but are in fact genetically driven nest building characteristics.
The graph shows the effect of selective breeding over 30 generations. The ordinate is the behaviour under selection (fearfulness versus fearlessness under stress) and the abscissa is the scores at each generation of selection.
The breeder’s equation shows the slope obtained under the three conditions.
The control condition is flat: no selection is taking place.
The selection conditions are almost mirror images, and the slopes represent the end effect of strong selection and high heritability. These are population statistics. One does not need to know how the genes do this, merely that it is possible, as the results demonstrate.
A detailed example of the equation in action is given by Razib Khan
http://blogs.discovermagazine.com/gnxp/2007/05/breeding-the-breeders-equation/#.WL2uyfnyg2w
I wrote a good and succinct reply to Thompson. Then hitting the wrong buttons, it vanished.
You have a real misunderstanding of Gilliam’s Brazil.
Between that and the near-contemporary remake of 1984, I much prefer Brasil.
However, Gilliam says the concept started on a grey day on the shores of Wales.
It is wonderful dystopian fiction,
the worse thing about it is the US woman.
It is a shame that she was at the centre for a while, always those parts are irritating.
“You have a real misunderstanding of Gilliam’s Brazil.” – I do?
Thank you for your response. I like Khan’s derivation of the breeder’s equation for a simple case. But I still need to think about it. Anyway, for a simple case of heritability and selection he seems to derive S, R and h^2 independently and then shows that they fulfill the breeder’s equation: R=S*h^2.
As far as the Fig.1 is concerned, it is not a brilliant example of breeder’s equations at work. The graphs are consistent with the breeder’s equation but they do not illuminate the working of the breeder’s equation. The graphs show that the ordinate changes by approx. the same amount of ∆Y (it could be R) at each generation which leads to relatively constant slope. The breeder’s equation tells us that R is proportional to S and h^2 in one step. It does not tell us that in the next step S and h^2 or their product will remain the same. You can have a curve w/o a constant slope that at each step obeys the breeder’s equation. The fact that the slope was constant in this case has nothing to do with the breeder’s equation, I think.
damn, I seriously hope I don’t turn into my father. that would give me depression.
Did not mean to argue that the breeder’s equation must equal a slope, and as far as I can see never said that.
Illuminating the workings of the breeder’s equation is a deeper matter, what I claimed was merely that: “the findings are a brilliant example of the breeder’s equation in action” and this was but one example.
In action, you can see that the effects vary somewhat from generation to generation, though a slope has emerged. This could be due to measurement variability in the open field test (it will not perfectly capture fearlessnes) but also gives an indication that selecting the most fearless mice for breeding the next generation is not perfectly correlated with fearlessness in the progeny.
One presumes that under even severe selection there is some regression to the mean.
But Batty’s trying to be like an artist, yet he knows he can’t live the ten thousand hours that it takes to nail it. A tragic lament that so often turns violent, alas.
maybe
if happiness is being in the middle 64% of all the various bell curves and unhappiness is caused by one of the many different extremes
While the form of the breeder’s equation : R=S*h^2 is simple and straightforward, its theoretical derivation does not exist in a general case. In other word this equation is not really valid in general While I do not know the story of this equation, I presume it was derived empirically, though I wonder how the actual breeders came up with the definition of heritability to be the ratio of variances when they were at it. The breeder’s formula can be proven in simple cases of Mendelian genetics just like Khan (*) did in the linked by you page.
You have brought up the equation in your article and you clearly stated that the “the findings are a brilliant example of the breeder’s equation in action”. I was wondering why because the curves in Fig. 1 as I wrote before do not illustrate nor validate the breeder’s equation. The curves illustrates the breeding outcome in this particular experiment but one can’t find in the graph neither S nor h^2. So I wondered why you wanted to beef up your article with the statement that is nebulous at best if not just plainly misleading. Why this insistence on the breeder’s equation? Perhaps the following quote may hint the answer to this question:
(*) BTW, Khan’s proof of the breeder’s equation is not really satisfying. He finds a formula linking R with S (R=k*S) and then points out to the proportionality coefficient (k) as being the heritability. However he doesn’t demonstrate that it actually is heritability. Perhaps I need to study it some more.
You mean that people who don’t fit in end up emigrating? And hence culture also shapes genetics and hence we have a cultural-genetic complex that is far more viscous than either part alone?
Fascinating!
Then why is there a scientific replication crisis.
The derivation from Khan depended on Hardy-Weinberg principle,
https://en.wikipedia.org/wiki/Hardy%E2%80%93Weinberg_principle
Note the fine print,
“””The Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law, states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. These influences include mate choice, mutation, selection, genetic drift, gene flow and meiotic drive. Because one or more of these influences are typically present in real populations, the Hardy–Weinberg principle describes an ideal condition against which the effects of these influences can be analyzed.”””
Thus it sounds attrative at the macro level but will it be true at the finer grain level? It is like will a person says that he feels only a slight chill when one of his hand is in a bucket of liquid nitrogen and the other is on a red hot burning coal? What will the real world situation be instead of the ideal genetic combinatronics? Regression to the mean is, well, regressive and well contained. It cannot explains why the Ashkenazi Jew are smarter than both their proto ancestors of ancient Europeans and ancient Jews.
Murray had said that the US society has increasingly coming apart,
http://econlog.econlib.org/archives/2012/01/the_bell_curve.html
“””Today, that is no longer true. Americans have formed a new lower class and a new upper class that have no precedent in our history.”””
I set out to investigate the academic attainments of the children generation NmsNdx for the town/city region with respect to (mostly) their parent genaration EduNdx both relative to the averages of their relevant peers at the state of California. For the children I used the data of the National Merit Scholarship semi-finalists for California and for the parents the fraction with university degrees from Murray’s dataset which was aggregated from the US Census data.
Such investigation of population dynamics has been carried out since the 1970s and it was one of the active areas where real life chaos theory situations were investigated and conditions other than regression to the mean were found, e.g.
R.M. May, “Bifurcation and dynamic complexity in ecological systems”, Ann NY Acad Sci 316 (1979)
Interestingly similar results to the above paper where a similar cubic equation proved by May to be chaotic was found. In summary three distinct regions were found with the extreme two regions being running away from the mean rather than regression to the mean were noted, i.e. in one region smarter parent generations have on average children that outperformed tham and the other region with less smart parents whose children generation performed worse than them. Only in the mid region the performance of the children on average was regressing to the mean.
I constructed the index WobegonNdx=NmsNdx/EduNdx where WobenNdx gt 1 means that the children out-performed their parent generation.
NmsNdx le 0.9892 : WobegonDrop (runaway); cases=52
0.9892 lt NmsNdx le 2.1907 : WobegonMix (regressive); cases=35
NmsNdx gt 2.1907 : WobegonSurge (runaway); cases=125
There are another 891 CA towns/cities which do not produce any NmsSF and presumingly in the WobegonDrop region. Thus regression to the mean only occurs in 35/1103 towns/cities while the rest are assortative runaways from the mean. These are the latent driving forces that result in the society to be coming apart as noted by Murray. And they might be the forces that drive Darwinian evolution.
Some particular result, in the city of Atherton, the socio-econmic percentile is at 99.99%, median income at $250K, EduNdx at 2.44 times higher than state average, it would seem to be very hard for the children to perform much better than that but still on average for the children generation the NmsNdx is at 49.08, giving the WobegonNdx=NmsNdx/EduNdx=20.11.
On the other hand for the Los Angeles city, SESpctl=38.0%, IncK=$55.22K, WobegonNdx=0.09/0.86=0.11 . More data in the later part of https://westhunt.wordpress.com/2017/02/22/neurodiversity/#comments
Interesting points, and I will try to respond, though some things are still not clear to me as regards the levels of proof you are looking for.
“The grand aim of all science is to cover the greatest number of empirical facts by logical deduction from the smallest number of hypotheses or axioms.” So, the Breeder’s equation aims to do that. If, looking at the data from mouse, and from domestication of foxes, and all other selection studies, one can find a better way of expressing what is happening, then of course the new axiom will replace the old one.
You say: “In other words this equation is not really valid in general”. If so, which facts does it not cover? What contrary findings are the exception to the rule? How should the rule be changed?
Anyway, here is Greg Cochran’s take on it:
https://westhunt.wordpress.com/2013/06/07/the-breeders-equation/
I saw the Greg Cochran’s piece before and I was wondering where he gets his stuff from. Take a look at the first two paragraphs. First he introduces the breeder’s equation and then in the next he states that if both parents have IQ=120 and if population mean in 110 and if heritability is 0.5 then on average children’s IQ will be 110. How one suppose to get it form the breeder’s equation? This way?
10=X=(120-100)*0.5 and then 100+X=110 is mean children IQ? But is it really true? Was it verified? Any paper that compares IQ of parents and children? Obviously the result will depend on heritability, so heritability must be established from other studies than parents–>children IQ’s.
The purpose of selecting breeding is to beat the pull of the regression to the mean. And how is it done? By changing the mean, i.e, by discarding offsprings that lower the mean and breeding the offspring that have higher mean than parents.
Not exactly. It is regressive for parents who are above the average but not for the parents who are below the average as children of the latter suppose to be smarter than their parents.
The pull of the regression to the mean is beaten by the process of selective breeding. In selective breeding you accomplish this by changing the mean. So obviously Hardy–Weinberg principle does not apply. You select offspring that exceed parents trait for the next stage of breeding and discard those who were regressed to the mean. Did Jews kill their more stupid children? Or they just did not let them breed so the less intelligent ones had to defect to the gentile population in search of the mates and ceased to be Jews?
The question how valid is the breeder’s equation is another matter.
But what you and Murray are concerned with most likely has nothing to do with genetics but rather with some kind of Flynn effects.
The mechanism is that higher ability people are more marriageable and have more surviving children, perhaps 4 to less able people’s 2 surviving children.
Probably not. I have had a very bad cold and high fever in the last few days, so excuse that, please.
Still, the only parts that seem relevant to or prophetic for the USA are the behaviour of the special police and treatment of suspects.
Gilliam is a US person, but it is a very Brit. dystopia. Ruling power is like late 70s Conservatives meet East Germany.
I also like the way Lowry has a reality breakdown, like a PKD character, at some point. Don’t even think it was intentional at first (at least the timing), just something Giiiam liked, that happened by chance in the editing process.
Where it (the reality breakdown) is is always interesting to me, I think immediately before or after the struggle over one desk in two tiny cubicles.
I never saw the original US release, with the ‘happy ending’ , but it is funny that a happy ending was ordered there, the version Gilliam wanted (but a little shorter) was on screen everywhere else it was shown, AFAIK.
I like the article, Dr. Thompson, but re. Bladerunner and Do Androids, the central theme re. replicants is almost a complete inversion.
In the novel, the replicants are incapable of empathy. There is a scene where two of them enjoy pulling the legs off a harmless spider to illustrate this.
Much more, like how in the movie, everwhere except JF Sebastian’s place is crowded, the trade in ersatz animals has no explanation.
Even the title is from Burroughs, not Dick.
Love Bladerunner, but is a shame that there will never be a film of Do Androids (at least in the lifetimes of anyone over, say, ten, with the insane endless extension of IP rights by the US).
Ridley Scott has made a few great films, but is an ignoramus as a reader, even boasting of never having read the slim volume that is Do Androids.
Faithful PKD-based movies：
A Scanner Darkly
Screamers
Impostor (the 40 min version, the feature-length version is rubbish)
A French one, title something like Barjo, haven’t seen it, not SF, have read the novel. Based on Confessions of a Crap Artist, IIRC.
Fun and close to faithful：
Total Recall (not the recent one)
Great but almost totally unfaithful ：
Bladerunner
Total crap：
All of the others
As for all of the others, what a waste. One may be pretty sure that the Bladerunner sequel will be execrable, too.
Bear in mind that massive scientific community seems a recent phenomenon in human societies. There is time to adjust it.
Interestingly someone tell me a hard truth about academic teachers in contrast with regular school teachers, specially those on the public schools. “Academic/university teachers are the only ones who can be a horrible teacher and don’t be dispensed”.
“Capitalistic” logic to the innovation. Academics who not just don’t innovate but also buy evidently wrong and problematic thesis must be go.
Sorry to say Che, but I have an impression that you misunderstood most of the movie Brazil, for example you say:
Brazil has been done in the British retro look because:
1) it is a kind of continuation of Monty Python (“Ducts ….),
2) because at the time of the making the UK was much more a bureaucratic country than US,
3) the UK was also the highest surveillance country in Europe, all justified by the IRA terror at the time, and
4) the retro look is the expected outcome of Thatcherism in Britain of the time.
I shudder at a mere thought of putting Monty Python style humour of this movie in front of some US background!? It would never work, maybe Gillian even tried.
The movie’s retro look puts a very powerful emphasis on the story and the characters instead of the production design and special effects (typical to SF genre), in which the movie engages only on rare but most significant occasions (dreaming). An additional point is that with the destruction of the middle class in the West, an even worse look is prevailing in some areas – just look at US urban jungles now. I have been to East Germany and I can tell you that nothing there ever looked like Detroit.
I have been showing Brazil to many of my friends and past girlfriends and observing their reactions. What you call the look of “East Germany” is exactly what turns off most people who are incapable of understanding this movie. It is just not flashy and shiny enough to keep their attention for two hours. There are also people who are too-US (narrow-minded) to understand the subtlety of this British movie paid for by US.
You are also too judgemental about the Blade Runner, making several valid points but again outside of context.
“If so, which facts does it not cover?”
The formation of Ashkenazi Jews who are smarter than their proto ancestors of ancient European and ancient Jews. There were no other smarter pop group they could regress up to. That would require h^2 to be greater than one which is hard to exdplain.
“How should the rule be changed?”
Copy Einstein’s example of inserting a gravitational constant. Thus
R = w h^2 S
where w is the Wobegon constant, then H^2 dont necessary have to be greater than one.
Rather than plugging h^2 value from thin air, the w h^2 value can be obtained from the regression of the pop data. In my case from only the available data the R and S are of different measures of the same charateristic but as R is monotonically related to S I can just regress on log(R) against S and get the w h^2 value.
“It is regressive for parents who are above the average but not for the parents who are below the average as children of the latter suppose to be smarter than their parents.”
Not from my empirical data points rather than your hand waving. The particular examples for Atherton and LA city I provided demonstrated these, i.e. for Atherton EduNdx=2.44, NmsNdx=49.08, WobegonNdx=20.11, for LA EduNdx=0.86, NmsNdx=0.09, WobegonNDx=0.11, both are the reverse of what you claimed. And they are not isolated data points, there are 125/212 cases similar to that for Atherton and 52/212 cases similar to that for LA city. Alternatively, the rest of 891 cases with NmsNdx=0 are closer to that for LA with NmsNdx=0.09 rather than NmsNdx=0.9892 demarcation line, the cases similar to that for LA might be 943/1103 cases, the reverse of what you claimed. These are actual empirical data points.
“But what you and Murray are concerned with most likely has nothing to do with genetics but rather with some kind of Flynn effects.”
Here is a recent refreed paper that investigated the distribution of allels withlatitudes,
JPA Gardner and K-J Wei, “The genetic architecture of hybridisation between two
lineages of greenshell mussels”, Heredity (2015) 114, 344–355.
See Gardner’s fig 2,
“Figure 2 Sigmoidal cline plots for the 10 alleles showing greatest change in allele frequency as a function of latitude. In each case, the cline fit is based on data from 12 populations; the HSB population (circle ○) and the BGB population (black triangle ▲) shown for comparison. The hybrid zone is located in the
areas of steepest gradient of change of allelic frequency. Note the different y axis ranges that are necessary to show detail of the sigmoidal curves.”
In Gardner’s case the two variables are Gene Freq and latitude. In my cases the two variables are NmxNdx and EduNdx. The Gardner’s scatter plots of the data points are similar to that for mine. Those are also actual empirical data points.
If the force of regression to the mean is strong, there will simply be one big blob of hybrid zone. If the hybrid zone is so tiny what use is the narrative of regression to the mean in real life situations? Evolution with regression to the mean and natural mutations would be very slow, every time a new phenotype appears their descendents migh be pulled back to the pop mean. Evolution with digression away from the mean could fast-track the process in a few generations, and this could be the process for the formation of the Ashkenazi Jews, the smarts’ descendents getting smarter, rather than being pulled back to the old pop mean and in time they will form a new distinct population group. Thus mentioning regression to the mean and Darwinian evolution might be a bit oxymoronic. It is digression from the mean that forms speciation.
It is also interesting that the dynamic population model shows both possibly the mechanics of Flynn effects and Woodley’s dumbing down concurrently. Thus it could be that the proper selection of sample is very important.
Despite British efforts to keep the IRA terror campaign hush-hush, their “cover” was blown after a spate of “car-jacking” robbery attempts in South Florida that left more than one British tourist dead. This resulted in the British issuing a travel advisory regarding British tourists visiting Florida, suggesting that the gangs targeting foreign tourists driving rental cars made that portion of the U.S. dangerous.
The then Florida Governor Lawton Chiles retorted, “Oh yeah? What about the IRA bombings “over there”?
Yes, what about the IRA bombings? The terror attacks in conjunction with the way the authorities responded to them was the subject of “Brazil”, although this was not known to most U.S. viewers of the movie. Most of us in the U.S. knew about The Troubles in Northern Ireland, but we didn’t make the connection that in addition to their tactical campaign in Northern Ireland, the IRA had a “strategic campaign” of terror in England itself. Heck, I visited London on business in the 1970’s during the “if you see something, say something” era, was even stuck in traffic for my departure from London Heathrow where my host asked a police constable about the holdup and was answered tersely “suspect bomb” (what we call a bomb scare), and I still didn’t make the connection to “Brazil” until after the Florida governor blabbed.
Since the 9-11 attacks, the U.S. has taken on the qualities of England depicted in “Brazil”, “security theatre”, “renditions”, the (argued to be) torture interrogations, the normalization of a permanent state of war, and so on. But the film was very much about the British experience with the Northern Ireland War.
Florida tourists of whatever nationality were easily identifiable when driving rental cars. The state, in its infinite wisdom, for years had all those rental car license plates start with the letter Y. They got a lot of heat from the business community about crime being a downer, so changed their ways.
All an enterprising local, or IRA guy, had to do was read the license plates and pick a target. After all, how many tourists wanted to travel back to Florida for trial after some BS scam or phony car accident or mugging. Oahu had that reputation for quite a while, too, although at least the return trip was to a nicer place.
hmm. correction. cosmological constant.
All those moments will be lost in time, like tears in rain.
I am grateful to you for your far better knowledge of both the books and the films.
I found the following derivation of the breeder’s equation:
http://www-liphy.ujf-grenoble.fr/pagesperso/bahram/Evolution/evolution_lectures.pdf
Thus the equation is made true by a clever (tautological) definition of the heritability. In other words the heritability is what it must be to make the equation true. The heritability in the equation is defined by the breeder equation as a nonnegative smaller than one coefficient that is necessitated by the fact (which is intuitively true) that R < S. There is no independent definition of the heritability for the purpose of this equation. However we know that the breeder's equation often is not true but this can be stated when the heritability is defined independently of the equation. Here various reasons for which the breeder's equation might not be valid are given:
http://nitro.biosci.arizona.edu/Nordicpdf/WLChapter04.pdf
However the most important fact that is more general than the breeder's equation is the inequality
R < S
which implicates the "regression towards the mean". More correctly the inequality should be written for absolute values: |R|<|S| so the fact that the regression towards the mean can be Up not only Down is not overlooked. According to this inequality the offspring of short parents will be taller while offspring of tall parents will be shorter (statistically).
Consequences of regression to the mean
(1) The fact that |R| < |S| implies that standard deviation of any trait within randomly mating population should be shrinking. In the end it should shrink to zero.
Was it observed? Are grasses on a meadow more alike now than 1000 years ago? Was standard deviation of IQ larger in the past than now?
(2) Can mean (of a particular trait) of population change? Not according to the breeder's equation providing the heritability is the same when trait is smaller than the mean and when it is larger than the mean.
Which mean? This is the question about the meaning of the mean that sits in the breeder’s equation. Consider the following situation. Let suppose that all people with IQ>100 vanished. Then the mean of the remaining population will be smaller than IQ=100 (say IQ=80) however the breeder’s equation will be still working and the regressing to the old mean of IQ=100 will continue, so the actual mean of the population will be increasing. Thus there is an important distinction between the actual (manifested) mean of the given population and the mean that plays the role in the breeder’s equation. Let suppose that the mean of IQ=100 that is currently observed is not the mean that plays the role in the breeder’s equation. In this case we should observe the regression to the mean that sits in the breeder’s equation. What if the mean that sits in the breeder’s equation is larger than 100? Then we should observe a drift akin to the Flynn effect.
If the manifested mean is smaller than the mean (that sits in the breeder’s equation) such a population could be called as the one that not realized its potential. Due to the regression to the mean effect the manifested mean of this population will increase.
For these conclusions the validity of breeder’s equation is not important. It suffices to observe that |R| < |S|.
You are rather harsh, and none of what you say is relevant to my post to which you are replying. For example, did I say that the mix of Conservative Party ruling types and East German style enforcers with working-class Brit accents was stupid?
No. Rather, I thought it was brilliant.
Monty Python was popular in Japan, so of course I caught those references, though they are quite few.
Your reply is nonsensical since it has nothing to do with my two posts that you lamely try to attack by making your own assumptions to put things I did not say in my mouth.
How was anything ‘out of context’?
I said that I think that it was a great movie. My complaint is only that the mad US eternal copyrights campaign means that nobody over the age of ten will ever see a film of the real Do Androids Dream of Electric Sheep, if such is ever made.
My points were how few supposedly PKD-story based movies are good or faithful to the source, and that Ridley Scott is self-confessedly retarded as a reader.
You can refute neither.
What you misunderstood is my words having read Do Androids Dream of Electric Sheep, perhaps you may try reading it some time?
I am enough of a Bladder Runner fan to have bought and read both of the sequels by Kevin Jeter, they are not masterpieces, but he tries to reconcile the film with the short novel, and comes up with many interesting scenes in the process.
He was uniquely qualified, having lived in the same house with PKD, and having appeared as a character in Valis.
Bet you didn’t know any of that.
Meanwhile, youtube and other US sites have absolute permission to steal any content they want from minor players, it is a clearly official US strategy, sometimes called ‘digital crack’.
I hope that you are not being sarcarstic, but sense that it is not, read them all (except one of the early non-SF ones, Mary and the Giant, I look forward to reading it).
Have watched the films that I do not think rubbish many times. BTW, if you have not seen A Scanner Darkly, or read it, I strongly recommend both.
The movie, rotoscoped, has probably Keanu Reeves’ strongest dramatic performance.
Almost the last for Downey jr. before his Iron Man stupidity. I love him as an actor, but won’t pay a cent to see current superhero garbage,
No sarcasm. Was introduced to Dick’s writing by a literary friend, and have had only a glancing exposure to “Do androids dream” so yet another set of readings are now in my metaphorical in-tray for future reading.
Thanks for your comments.
My comments #50 and #51 were really meant for you and for dux.ie.
Both Walsh’s and your arguments falls into the trap of Zeno paradoxes, https://en.wikipedia.org/wiki/Zeno%27s_paradoxes
Look at the larger picture, only digression from the old population mean causes new phenotype/specie to form. Regression to the mean with statistically one step forward one step back will reduce all living things to a single specie. Only digression from the mean could propel the Ashkenazi Jews’ IQ to much higher than their proto ancient Jews and ancient European ancestors in only a few generations.
The explanation of Jean Paul Van Bendegem for breaking the Zeno paradoxes seems to be the best. The changes are not infinitely divisible and there is a finite discrete minimum change (allele) which will cause the system to break through the boundaries and once crossed previous assumptions and constraints are most probably no longer valid.
“Only digression from the mean could propel the Ashkenazi Jews’ IQ to much higher than their proto ancient Jews and ancient European ancestors in only a few generations.”
I see you are obsessed with some Jewish IQ Problem. How many generations is a few generations? You have any data on Jewish IQ from antiquity and Middle Ages? Are you sure you understand the regression to the mean in the context of the breeder’s equation? Because you know, despite of that regression you can breed 1000 pound pumpkins. So I do not see any reason why you could not breed a Jew with a really big nose.
Theoretical predictions are fine but at some stage you have to have reality check. Do you believe in Darwinian evolution or that all higher order life are created during the big bang?
This is after all a blog on intellegence.
https://en.wikipedia.org/wiki/Ashkenazi_Jewish_intelligence#.22Natural_History_of_Intelligence.22
“””In a television interview, Cochran said: “…So if [ Jews] (statistically and positively accumulatively net) increased a third of an IQ point per generation, that would almost certainly be enough to make this effect happen.” “”” With my own emphasis.
Over a thousand years statistically and consistently positive accumulation, no regression to the mean. If a modified breeder equation R = (1+m) h^2 S is used, then R ge or le S, then regression to the mean R lt S is only one of the possible outcome and it is not the driving force for the above condition, the improvement accumulated over a long time.
“a third of an IQ point per generation” – Where did you get this number from?
For the breeder’s equation to work (in selective breeding) one must understand what S really is. S is not determined at every step of the selective breeding by the mean of trait of the population at the starting point. The mean keeps changing. It keeps going up. That’s why you can beat the regression to the mean with selective breeding process though you must put up with it at each single step. If it wasn’t so, there would be no selective breeding. One could write a recursive equation for it.
What is justification for the ad hoc formula R = (1+m) h^2 S you came up with? Just because you want to beat regression to the mean and get R > S? Guess what, I propose the following formula E=2*mc^2 so we can have more energy from nuclear power plants and at a lower cost. My desire is stronger than yours and even more noble, so I am sure my formula have higher chances to be correct than yours.
Providing that there is no mutations R < S always! This inequality implies regression to the mean at each step. But in the selective breeding process the mean to which the regression occurs keeps increasing because the mean of offspring's population is higher than the mean of original population. So as long as you keep selecting new parents with a maximum of desired trait in the offspring population you end up beating the regression to the mean in a long run.
Try to understand how to breed large pumpkins so you may figure out how to breed Jews with large noses.
“”” “a third of an IQ point per generation” – Where did you get this number from? “””
It is from Cochran’s paper, go read their paper.
“”” What is justification for the ad hoc formula R = (1+m) h^2 S you came up with? “””
You brough up Walsh’s paper. It is in their paper. Go read again the paper you youself suggested. It is also in Cochran’s paper.
Thanks for your articles.
I stick by my list of the few faithful film adaptions, I am not wanting to repeat myself, but will leave it to the below.
Seriously, most strongly I recommend a close reading of A Scanner Darkly, then watch the movie.
Not perfect, but the closest.
As a second, read ‘Do Androids’ and consider it against Bladder Runner, have an old pdf of the inermediate stage, enough of a fan to have closely read it all.
I would qualify your helpful observation by noting that you don’t need to choose “parents with the maximum of the desired trait” to keep on improving the stock. It suffices that the selected parents are above average.
Indeed that overstates the required breeding discipline. Long ago I calculatd that a 100 to 115 imprivement in population IQ could have been achieved in 500 years by simply preventing the under 80 (or 75) IQ people from reproducing. Greg Cochram rejected the implied explanation of Ashkenazi IQ rather crossly but didn’t deny the logic of the calculation.
So you just do any of whatever is required to raise the average each generation. Eating the worst young seems efficient.
” It suffices that the selected parents are above average.” – Correct!
Or that, in a still randomly mating population, you have excluded the poor performers in each generation before you allow the others to breed..
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5319977/