Montag, 30. März 2015

Was erfasst ein Intelligenztest?

Im Deutschen ließe sich ein Intelligenztest auch als Denktest bezeichen, da er eben erfasst, wie effektiv (wie wirksam) eine bestimmte Testperson denkt. Unter Denkvorgang kann man eine Art (Ordnungs-)Suchvorgang verstehen. Je effektiver eine Person denkt, desto effektiver spürt sie Ordnung (Zusammenhänge, Muster, Strukturen, Regel- und Gesetzmäßigkeiten, Wiederholungen, Gleich- und Ungleichheiten, …) in ihrer Um- und Innenwelt auf / desto effektiver stellt sie Ordnung in ihrer Um- und Innenwelt fest.

[Siehe auch: Why is thinking necessary?]

Samstag, 28. März 2015

Blindness to Equality/Inequality:

There is a certain tendency to think that ones appearance and the appearance of ones siblings are quite different, while, quite often, non-family members experience them as very similar. From a European perspective "all Chinese look alike"; and it has also been said, that, from a Chinese perspective, "all Europeans look alike".
So it seems as if there are two cognitive tendencies/biases: (A) the tendency to perceive more similarity than there actually is (B) the tendency to perceive less similarity than there actually is.
Or in other words: (A) the tendency to perceive the similarities and to ignore the differences (B) the tendency to perceive the differences and to ignore the similarities.
Bluntly said, in some situations people appear to be blind to equality, while in other situations people appear to be blind to inequality.

Donnerstag, 26. März 2015

The genomic-level heritabilities of preparedness and plasticity in human life history: the strategic differentiation and integration of genetic transmissibilities

The genomic-level heritabilities of preparedness and plasticity in human life history: the strategic differentiation and integration of genetic transmissibilities (provisional pdf)
Michael A. Woodley of Menie, Aurelio J. Figueredo, Tomas Cabeza de Baca, Heitor B. Fernandes, Pedro S. Wolf and Candace Black (2015)


The Continuous Parameter Estimation Model is applied to develop individual genomic-level heritabilities for the latent hierarchical structure and developmental dynamics of Life History (LH) strategy LH strategies relate to the allocations of bioenergetic resources into different domains of fitness. LH has moderate to high population-level heritability in humans, both at the level of the high-order Super-K Factor and the lower-order factors, the K-Factor, Covitality Factor, and General Factor of Personality (GFP). Several important questions remain unexplored. We developed measures of genome-level heritabilities employing an American sample of 316 monozygotic (MZ) and 274 dizygotic (DZ) twin dyads and a Swedish sample of 863 MZ and 475 DZ twin dyads. This novel heritability index measures individual genetic transmissibility, therefore opening new avenues for analyzing complex interactions among heritable traits inaccessible to standard structural equations methods. For these samples: (1) moderate to high heritability of factor loadings of Super-K on its lower-order factors is demonstrated, evidencing biological preparedness, genetic accommodation, and the gene-culture coevolution of biased epigenetic rules of development; (2) moderate to high heritability of the magnitudes of the effect of the higher-order factors upon their loadings on their constituent factors, evidencing genetic constraints upon phenotypic plasticity; and (3) that heritability of the LH factors, of factor loadings, and of the magnitudes of the correlations among factors are weaker among those with slower LH speeds, demonstrating that inter-individual variation in transmissibility is a function of individual socioecological selection pressures.

Dienstag, 17. März 2015

Is Education Associated With Improvements in General Cognitive Ability, or in Specific Skills?

Is Education Associated With Improvements in General Cognitive Ability, or in Specific Skills?
Stuart J. Ritchie, Timothy C. Bates, and Ian J. Deary (2015)


Previous research has indicated that education influences cognitive development, but it is unclear what, precisely, is being improved. Here, we tested whether education is associated with cognitive test score improvements via domain-general effects on general cognitive ability (g), or via domain-specific effects on particular cognitive skills. We conducted structural equation modeling on data from a large (n 1,091), longitudinal sample, with a measure of intelligence at age 11 years and 10 tests covering a diverse range of cognitive abilities taken at age 70. Results indicated that the association of education with improved cognitive test scores is not mediated by g, but consists of direct effects on specific cognitive skills. These results suggest a decoupling of educational gains from increases in general intellectual capacity.

Montag, 16. März 2015

By their words ye shall know them: Evidence of negative selection for general intelligence in vocabulary usage since the mid 19th century

By their words ye shall know them: Evidence of negative selection for general intelligence in vocabulary usage since the mid 19th century (provisional pdf)
Michael A. Woodley of Menie, Heitor B. Fernandes, Aurelio José Figueredo and Gerhard Meisenberg (Mar 2015)


It has been theorized that declines in g due to negative selection stemming from the inverse association between completed fertility and IQ, and the Flynn effect co-occur, with the effects of the latter being concentrated on less-heritable non-g sources of intelligence variance. Evidence for this comes from the observation that 19th Century populations were more intellectually productive, and also exhibited faster simple reaction times than modern ones, suggesting higher g. This co-occurrence model is tested via examination of historical changes in the utilization frequencies of words from the highly g-loaded WORDSUM test across 5.9 million texts spanning 1850 to 2005. Consistent with predictions, words with higher difficulties (δ parameters from Item Response Theory) and stronger negative correlations between pass-rates and completed fertility presented a steeper decline in use over time, than less difficult and less negatively selected words, which increased in use over time, suggestive of a Flynn effect. These findings persisted when explicitly controlled for word age, literacy rates and temporal autocorrelation. These trends constitute compelling evidence that both producers and consumers of text have experienced declines in g since the mid-19th Century.

You Can Give a Boy a Doll, but You Can't Make Him Play With It

You Can Give a Boy a Doll, but You Can't Make Him Play With It
Christina Hoff Summers (2012)

"One of the largest and most persistent differences between the sexes are children's play preferences." *

[via Oliver Scott Curry]

*the quote is from David Geary

Samstag, 14. März 2015

Rolling Dice & Regression to the Mean:

"Imagine we’ve thrown 3,600 [dice]. Purely by chance we’d expect about 600 of them to show a 1, about 600 a 2, and so on up to about 600 showing a 6. Now let’s pick all those showing a 6, ignoring the others. Since each of these shows a 6, the average value they show is obviously also a 6. We then throw all these again. By chance again, we’d expect about 100 of them to show a 1, about 100 a 2, and so on up to about 100 of them showing a 6. The overall average of the numbers showing on the dice on this second set of throws will be about 3.5 (it’s just [100 × 1 + 100 × 2 + … + 100 × 6] ÷ 600). Now the average has decreased from 6 the first time we threw these particular 600 dice to 3.5 the second time we threw them."

[According to Cochran, the "final" IQ that an individual will get is not only influenced by genes, but also influenced by chance. Probably some day it will be possible to predict the range in which an individual's adult IQ will fall with high accuracy at the moment of birth (the individual's intelligence genes will be known at birth or even earlier, but it will be unknown what "chance events" the indidviual will encounter during its life-time). In other words, at the moment when egg and sperm cell fuse it becomes determined what numbers there are on "an individual's IQ-dice". But the result of the dice roll (the adult's IQ-score) won't be known until the dice "stop rolling" (the adult IQ-score will be measured) in adulthood.]

Source of the quote:
The Improbability Principle (2014) by David J. Hand

Gerhard Roth über Persönlichkeit:

Vortrag von Prof. Herwig Birg zum Thema Demografie (Jan 2015):

Neue Buchveröffentlichung (Dez 2014):
Die alternde Republik und das Versagen der Politik: Eine demografische Prognose

Homepage von Herwig Birg:


Ferdinand Knauss: Ihr Institut für Bevölkerungsforschung und Sozialpolitik an der Universität Bielefeld, 1981 auf Initiative des damaligen nordrhein-westfälischen Ministerpräsidenten Johannes Rau gegründet, wurde nach Ihrer Emeritierung eingestampft.

Herwig Birg: Damals gründete man Institute noch auf Grund rationaler Argumente. Unser interdisziplinäres Institut mit fünf Wissenschaftlern war unabhängig von den Universitätsfakultäten und funktionierte tadellos. Doch es wurde von der CDU-Landesregierung unter Jürgen Rüttgers nach meiner Emeritierung aufgelöst – gegen alle Empfehlungen wissenschaftlicher Gremien innerhalb und außerhalb der Universität. Das gleiche geschah mit den demographischen Lehrstühlen der Universitäten in Bamberg und Berlin. Es gibt da ein großes Einvernehmen aller großen Parteien. In derselben Zeit wurden übrigens Dutzende von Lehrstühlen für Gender-Forschung geschaffen. An Geldnot lag es also nicht.

Dienstag, 10. März 2015

People talk slow:

There is a certain risk that viewing a talk (even if its content is interesting) gets boring after a short period of time. The reason for that phenomenon: people talk slow. If we read a book, we usually receive much more (relevant) information per time unit than when we listen to a talk. (That's likely the reason why reading books or articles is in general more stimulating than listening to talks.) A sometimes useful "solution"/improvement: e.g. for youtube-vidoes: (A) click at settings (the gear wheel icon) (B) set speed at 1.25;

Sonntag, 8. März 2015


"[One] of the defining features of play ... is its sensitivity to prevailing conditions. In general, play is an indicator of psychological and physical well-being (Held & Spinka, 2011). It is usually the first activity to disappear if the individual is stressed, anxious, hungry or ill."

Patrick Bateson (2014) 

The Child Quality-Quantity Tradeoff, England, 1750-1879: Is a Fundamental Component of the Economic Theory of Growth Missing?

The Child Quality-Quantity Tradeoff, England, 1750-1879: Is a Fundamental Component of the Economic Theory of Growth Missing?
Gregory Clark & Neil Cummins (March 2015)


A child quantity/quality tradeoff has been a central to economic theorizing about modern growth. Yet the evidence for this tradeoff is surprisingly limited. Measuring the tradeoff in the modern era is difficult because family size is chosen endogenously, and family size is negatively associated with unmeasured aspects of family “quality.” England 1770-1880 offers an opportunity to measure this tradeoff in the first modern economy. In this period there was little association between family sizes and family “quality”, and if anything this association was positive. Also completed family size was largely randomly determined, varying in our sample from 1 to 18. We find no effect of family size on educational attainment, longevity, or child mortality. Child wealth at death declines with family size, but this effect disappears with grandchildren. The switch in England in the Industrial Revolution to faster growth rates thus seems to owe nothing to declining family size.

Samstag, 7. März 2015

Statistical Misconceptions

Statistical Misconceptions
Schuyler W. Huck (2008)

Amazon; libgen;


Western Europe, state formation, and genetic pacification

Western Europe, state formation, and genetic pacification
Peter Frost & Henry C. Harpending (2015)


Through its monopoly on violence, the State tends to pacify social relations. Such pacification proceeded slowly in Western Europe between the 5th and 11th centuries, being hindered by the rudimentary nature of law enforcement, the belief in a man’s right to settle personal disputes as he saw fit, and the Church’s opposition to the death penalty. These hindrances began to dissolve in the 11th century with a consensus by Church and State that the wicked should be punished so that the good may live in peace. Courts imposed the death penalty more and more often and, by the late Middle Ages, were condemning to death between 0.5 and 1.0% of all men of each generation, with perhaps just as many offenders dying at the scene of the crime or in prison while awaiting trial. Meanwhile, the homicide rate plummeted from the 14th century to the 20th. The pool of violent men dried up until most murders occurred under conditions of jealousy, intoxication, or extreme stress. The decline in personal violence is usually attributed to harsher punishment and the longer-term effects of cultural conditioning. It may also be, however, that this new cultural environment selected against propensities for violence.

Freitag, 6. März 2015

Individual differences in accurately judging personality from text

Individual differences in accurately judging personality from text
Judith A. Hall, Jin X. Goh, Marianne Schmid Mast, and Christian Hagedorn (2015)


Objective: To examine correlates of accuracy in judging Big Five traits from first-person text excerpts.
Method: Participants in six studies were recruited from psychology courses or online. In each study, participants performed a task of judging personality from text and performed other ability tasks and/or filled out questionnaires.
Results: Participants who were more accurate in judging personality from text were more likely to be female; had personalities that were more agreeable, conscientious, and feminine, and less neurotic and dominant (all controlling for participant gender); scored higher on empathic concern; self-reported more interest in, and attentiveness to, people's personalities in their daily lives; and reported reading more for pleasure, especially fiction. Accuracy was not associated with SAT scores but had a significant relation to vocabulary knowledge. Accuracy did not correlate with tests of judging personality and emotion based on audiovisual cues.
Conclusions: This research is the first to address individual differences in accurate judgment of personality from text, thus adding to the meager literature on correlates of the good judge of personality.