Sonntag, 27. April 2014

Women remember more faces than men do

Women remember more faces than men do
Jenny Rehnman Agneta Herlitz
Acta Psychologica (March 2007)


Abstract

Women have been found to outperform men on face recognition tasks, specifically in the recognition of female faces. Men do not seem to exhibit a corresponding own-sex bias. To examine the generality and possible reasons for these patterns, 107 men and 112 women viewed faces of both children and adults of either Swedish or Bangladeshi origin, for later recognition. As expected, women were especially good at remembering female faces, but also outperformed men on male faces. Men did not show an own-sex bias. Thus, regardless of age and ethnicity of the faces, women performed at a higher level than men on both female and male faces, possibly reflecting enhanced interest in faces, and in particular, female faces.

Freitag, 25. April 2014

The Relationship between Learning and Intelligence

>In reviewing the then entire literature on the relation of learning to IQ I (Jensen 1979) arrived at a number of empirical generalizations regarding the conditions that seem most clearly related to the magnitude of the learning-IQ correlations, or the degree to which various learning tasks are g loaded. To summarize: Learning is more highly g loaded when:

1. learning is intentional and calls forth conscious mental effort;

2. the learning or practice trials are paced in such a way as to allow the subject time to think;

3. the material to be learned is hierarchical in the sense that the learning of later elements depends on mastery of earlier elements;

4. the material to be learned is meaningful in the sense of being related to other knowledge or experience already possessed by the learner;

5. the learning task permits transfer-from somewhat different but related past learning;

6. the learning is insightful, that is, it involves “catching on” or “getting the idea”;

7. the material to be learned is of moderate difficulty and complexity, in the sense of the number of elements that must be integrated simultaneously for the learning to progress;

8. the amount of time for learning a given amount of material to a specified criterion of mastery is fixed for all students;

9. the learning material is positively age-related, that is, some kinds of material are more readily learned (hence the concept of “readiness”) by older than by younger children; and

10. performance gains are measured at an early stage of learning something “new” than at a late stage of practice on the same task.<


Source:
The Relationship between Learning and Intelligence
Arthur R. Jensen (1989)
Learning and Individual Differences

[See also: http://meinnaturwissenschaftsblog.blogspot.co.at/2013/06/learning-iq.html]

Investment and Intellect: A Review and Meta-Analysis

Investment and Intellect: A Review and Meta-Analysis
Sophie von Stumm, Phillip L. Ackerman (2012)


Abstract

Cognitive or intellectual investment theories propose that the development of intelligence is partially influenced by personality traits, in particular by so-called investment traits that determine when, where, and how people invest their time and effort in their intellect. This investment, in turn, is thought to contribute to individual differences in cognitive growth and the accumulation of knowledge across the life span. We reviewed the psychological literature and identified 34 trait constructs and corresponding scales that refer to intellectual investment. The dispositional constructs were further classified into 8 related trait categories that span the construct space of intellectual investment. Subsequently, we sought to estimate the association between the identified investment traits and indicators of adult intellect, including measures of crystallized intelligence, academic performance (e.g., grade point average), college entry tests, and acquired knowledge. A meta-analysis of 112 studies with 236 coefficients and an overall sample of 60,097 participants indicated that investment traits were mostly positively associated with adult intellect markers. Meta-analytic coefficients ranged considerably, from 0 to .58, with an average estimate of .30. We concluded that investment traits are overall positively related to adult intellect; the strength of investment–intellect associations differs across trait scales and markers of intellect; and investment traits have a diverse, multifaceted nature. The meta-analysis also identified areas of inquiry that are currently lacking in empirical research. Limitations, implications, and future directions are discussed.

Delay discounting and intelligence: A meta-analysis

Delay discounting and intelligence: A meta-analysis
Noah A. Shamosh, Jeremy R. Gray
Intelligence (July - August 2008)


Abstract

Delay discounting (DD), the tendency to prefer smaller, sooner rewards to larger, later ones, is an important indicator of self-control. Assessments of DD superficially require individuals to make choices based on motivational processes. However, several lines of evidence suggest that DD may be systematically related to cognitive ability. We sought to provide a definitive assessment of the relation between DD and intelligence via quantitative research synthesis. A comprehensive literature search in two electronic databases yielded 24 eligible studies with 26 effect sizes in total. Meta-analysis revealed that, across studies, higher intelligence was associated with lower DD (random effects model weighted mean r = −0.23). Studies using reward schemes in which payoffs were subject to chance (i.e., involving either a chance of receiving one choice or random selection of one choice) showed weaker associations between DD and intelligence than did studies in which payoffs were all hypothetical or all real. Other moderator analyses revealed no influence of DD measure, DD choice paradigm, or intelligence type. There was no evidence of publication bias. Given clear evidence for a negative relation between DD and intelligence, investigating the processes that support or moderate this relation would be worthwhile.

Montag, 21. April 2014

Competitive Altruism: Development of Reputation-based Cooperation in Groups

Competitive Altruism: Development of Reputation-based Cooperation in Groups
Mark Van Vugt, Gilbert Roberts, Charlie Hardy (2005)


Abstract

This chapter advances a new theory of altruism, competitive altruism, which might account for the uniquely moral altruistic tendency of humans. The need to form coalitions with non-kin for dealing with internal and external group threats created selective advantages for people with altruistic reputations. We present evidence from the anthropological, social psychological and nonhuman literatures, which by and large support competitive altruism theory. Finally, we discuss some implications of this theory for the establishment of reputation-based cooperation in modern human society.

Mittwoch, 16. April 2014

National IQs: A review of their educational, cognitive, economic, political, demographic, sociological, epidemiological, geographic and climatic correlates

National IQs: A review of their educational, cognitive, economic, political, demographic, sociological, epidemiological, geographic and climatic correlates
Richard Lynn, Tatu Vanhanen (2012)


Abstract

This paper summarizes the results of 244 correlates of national IQs that have been published from 2002 through 2012 and include educational attainment, cognitive output, educational input, per capita income, economic growth, other economic variables, crime, political institutions, health, fertility, sociological variables, and geographic and climatic variables.

Samstag, 12. April 2014

Are acquiescent and extreme response styles related to low intelligence and education?

Are acquiescent and extreme response styles related to low intelligence and education?
Gerhard Meisenberg , Amandy Williams (2008)
Personality and Individual Differences


Abstract

Several lines of evidence suggest that acquiescent and extreme response styles are related to low education or low cognitive ability. Using measures constructed from the World Values Survey, this hypothesis is examined both in comparisons among individuals and comparisons among countries. At the individual level, both acquiescent and extreme responding are positively related to age and negatively to education and income in most world regions. Both response styles are most prevalent in the less developed countries. At the country-level, extremity is best predicted by a low average IQ in the country, and acquiescence by a high level of corruption.


---------------------------------------------------------------


>Response styles are important for the interpretation of personality and attitude measures by self-report. The most commonly observed response styles, also described as response biases, are acquiescent and extreme responding. Acquiescence refers to (unthinking?) agreement with statements, and extremity to a preferential use of the end points of the scale.<

>In the United States, responses of Blacks and Hispanics are more extreme than those of non-Hispanic Whites (Bachman & O’Malley, 1984; Hui & Triandis, 1989; Marin, Gamba, & Marin, 1992).<

>Smith (2004) found that European countries consistently scored lowest on measures of acquiescence derived from six different surveys. The highest-scoring countries were those with lesser levels of economic development, such as Panama, Nigeria, the Philippines, Pakistan and Bangladesh.<


Results:

>Extremity and acquiescence were positively correlated, with r = 0.241 at the individual level (N = 79,053 respondents) and r = 0.601 at the country-level (N = 79 countries).<

>[Differences] between world regions are substantial: up to 1.52 within-country standard deviations for acquiescence and 1.33 standard deviations for extremity.<

>Both response biases are more prominent in economically less developed regions such as Africa, South Asia and the Middle East.<

>Table 4 shows that at the country-level, acquiescence is most closely associated with high corruption and somewhat less with low lgGDP and low education. Extreme response style shows a different pattern, being most strongly associated with IQ, less with education, and even less with lgGDP.<

>The relationships of the response styles with country-level characteristics were explored further. Regression models were started with IQ, education, lgGDP, corruption, the average of political freedom and democracy, and Communist history. Nonlinear effects of the predictors were modeled by the inclusion of quadratic terms. During development of the models, alternative measures of the same construct were explored to improve the fit, and non-predictors were dropped. Tables 5 and 6 show the best-fitting models.<

>Acquiescence is predicted independently by high corruption and to a lesser extent by low education.<

>Table 6 shows that extreme responding is related mainly to low intelligence. This confirms the impression from Table 4, and also the pattern in Table 1 showing that extreme responding is most prevalent in the world region with the lowest average IQ (sub-Saharan Africa, average IQ 67 according to Lynn, 2006), and least prevalent in the region with the highest IQ (East Asia, average IQ 105). The effect of education is curvilinear, reducing extreme responding at low levels of education but raising it among the most educated samples. Among the economic and political indicators, only corruption has a significant effect.<



Discussion:

>[The] negative association between education and acquiescence that had been reported by some investigators (Heaven, 1983; Javeline, 1999; Mirowsky & Ross, 1991; Watson, 1992) is a nearly worldwide phenomenon. Also extreme responding is favored by low education and low income in most countries (Table 3). Therefore, psychological factors related to education, such as intelligence, rationality, self-control or self-confidence, appear to suppress both acquiescent and extreme responses.<

>The observation that extreme responding is most closely related to low IQ at the country-level (Tables 4 and 6) suggests that it expresses a crude ”either-or thinking” that is oblivious to fine distinctions. This is confirmed by the observation that within countries, extreme responding is reduced in persons with higher education and/or higher income.<

>[Acquiescence] appears to be favored by a lack of self-confidence, self-esteem or assertiveness, or a habit of subordination and conformity to others, and only indirectly by low intelligence.<

Eyes and IQ: A meta-analysis of the relationship between intelligence and “Reading the Mind in the Eyes”

Eyes and IQ: A meta-analysis of the relationship between intelligence and “Reading the Mind in the Eyes”
Crystal A. Baker, Eric Peterson, Steven Pulos, Rena A. Kirkland
Intelligence (May-June 2014)



Highlights

o Meta-analysis finds relationship between RMET performance and intelligence.

o Contrary to previous assumptions, RMET performance is influenced by intelligence.

o It is important to control for intelligence when using the RMET.

o Verbal and performance IQ contribute equally to RMET performance.


Abstract

Although the Reading the Mind in the Eyes Test (RMET; Baron-Cohen et al. 1997, 2001) has been used as a measure of mental state understanding in over 250 studies, the extent to which it correlates with intelligence is seldom considered. We conducted a meta-analysis to investigate whether or not a relationship exists between intelligence and performance on the RMET. The analysis of 77 effects sizes with 3583 participants revealed a small positive correlation (r = .24) with no difference between verbal and performance abilities. We conclude that intelligence does play a significant role in performance on the RMET and that verbal and performance abilities contribute to this relationship equally. We discuss these findings in the context of the theory of mind and domain-general resources literature.

[Thanks @ Andrew S.]

Freitag, 11. April 2014

On the Time Scale of Human Evolution: Evidence for Recent Adaptive Evolution

On the Time Scale of Human Evolution: Evidence for Recent Adaptive Evolution (full d.)
Gerhard Meisenberg (2008)


Abstract

To what extent did the genetic constitution of human population change in the recent past, and how fast are evolutionary changes proceeding in present-day populations? This review summarizes the available evidence about genetic adaptations that evolved after the dispersal of modern humans from Africa about 50,000 years ago and especially since the Neolithic Revolution and the emergence of the first civilizations. Evidence for recent evolutionary change is obtained from the molecular study of individual genes that have been or are currently under selection, and genomic studies that identify genomic regions under recent or ongoing adaptive evolution. The molecular evidence is complemented by archaeological evidence about population dispersals and prehistoric living conditions, and by evidence from historical demography about differential fertility and mortality in historic populations. The conclusion is that evidence for recent adaptive evolution is overwhelming, in many cases at the level of individual genes. There is also evidence that in many cases the selection of adaptive traits occurred in recent historic times. These adaptations evolved in response to climatic conditions, the nutritional changes brought about by the introduction of settled farming, exposure to new diseases, and the social conditions of civilized life. There is evidence that compared to earlier times, human adaptive evolution has accelerated massively since the Neolithic Revolution, possibly by a factor of about 100. Because historic and evolutionary time scales overlap, gene-culture coevolution is emerging as a major unifying theme in anthropological research.

Mittwoch, 9. April 2014

Ability Differences - Differences in Degree and Differences in Kind:

>[Ability differences] consist of two types: differences in degree, and differences in kind. Bodily-kinesthetic ability offers many examples. People with a wide range of bodily-kinesthetic ability can play tennis. The difference between the way most people play tennis and the way that profes­sionals play it is huge, but it is a difference of degree. In contrast, doing a somersault with a full twist off a pommel horse is impossible for most people, no matter how much they might practice. The differ­ence in what they can do and what the proficient gymnast can do is one of kind. 
This point needs emphasizing. Educational measures such as test scores and grades tend to make differences among schoolchildren look as though they are ones of degree when in reality some of them are differences in kind. For example, a timed math test limited to problems of addition and subtraction, administered to a random cross-section of fourth-graders, yields scores that place children along a continuum distributed in a shape resembling a bell curve. Those scores appropriately reflect differences in degree: Some fourth-graders can add and subtract faster and more accurately than others, but they are all doing the same thing and almost all children can be taught to add and subtract to some degree. The same is not true of calculus. If all children were put on a mathematics track that took them through calculus, and then were given a test of calculus problems, the resulting scores would not look like a bell curve. For a large proportion of children, the scores would not be merely low. They would be zero. Grasping calculus requires a certain level of logical-mathematical ability. Children below that level will never learn calculus, no matter how hard they study. It is a difference in kind. Not only that: The child without the logical-mathematical abil­ity to learn calculus cannot do a wide variety of other things in math­ematics that are open to the child with the requisite level of logical-mathematical ability.
The same distinction applies to linguistic ability. Reading is something that almost everyone can be taught to some degree, and scores on tests of reading achievement will form a continuum with a distribution resembling a bell curve. But if we are talking about a classroom discussion of Macbeth among high-school seniors at the 20th percentile and 90th percentile in linguistic ability, the difference is more accurately seen as a difference in kind than as a difference in degree. Those at the 20th percentile will completely fail to under­stand the text in the same way that someone at the 20th percentile of bodily-kinesthetic ability will completely fail to do a somersault with a full twist.<

Sex Differences in Human Voice Pitch:



























The difference between male and female means (in pooled standard deviations, Cohen’s d) for voice pitch (measured by fundamental frequency -> F0) and other putative targets of sexual selection.
A sample of 630 US university undergraduate students. (D. A. Puts, unpublished data)


Source:
Evolutionary Perspectives on Human Sexual Psychology and Behavior
V. A. Weekes-Shackelford et al. (2014) -> D.A. Puts, L. M. Doll, A. K. Hill

Dienstag, 8. April 2014

The presence of an attractive woman elevates testosterone and physical risk taking in young men

The presence of an attractive woman elevates testosterone and physical risk taking in young men
R Ronay, W von Hippel (2010)


Abstract

The authors report a field experiment with skateboarders that demonstrates that physical risk taking by young men increases in the presence of an attractive female. This increased risk taking leads to more successes but also more crash landings in front of a female observer. Mediational analyses suggest that this increase in risk taking is caused in part by elevated testosterone levels of men who performed in front of the attractive female. In addition, skateboarders’ risk taking was predicted by their performance on a reversal-learning task, reversal-learning performance was disrupted by the presence of the attractive female, and the female’s presence moderated the observed relationship between risk taking and reversal learning. These results suggest that men use physical risk taking as a sexual display strategy, and they provide suggestive evidence regarding possible hormonal and neural mechanisms.

Freitag, 4. April 2014

Perceptual Mechanisms That Characterize Gender Differences in Decoding Women's Sexual Intent

Perceptual Mechanisms That Characterize Gender Differences in Decoding Women's Sexual Intent
C. Farris, T. A. Treat, R. J. Viken, and R. M. McFall (2008)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2890253/


Abstract

Men and women often disagree about the meaning of women's nonverbal cues, particularly those conveying dating-relevant information. Men perceive more sexual intent in women's behavior than women perceive or report intending to convey. Although this finding has been attributed to gender differences in the threshold for labeling ambiguous cues as sexual in nature, little research has been conducted to determine etiology. Using a model that differentiates perceptual sensitivity from decisional bias, we found no evidence that men have lenient thresholds for perceiving women's nonverbal behavior as indicating sexual interest. Rather, gender differences were captured by a relative perceptual insensitivity among men. Just as in previous studies, men were more likely than women to misperceive friendliness as sexual interest, but they also were quite likely to misperceive sexual interest as friendliness. The results point to the promise of computational models of perception in increasing the understanding of clinically relevant social processes.


Mittwoch, 2. April 2014

The relationship between Microcephalin, ASPM and intelligence: A reconsideration

The relationship between Microcephalin, ASPM and intelligence: A reconsideration
Michael A. Woodley, Heiner Rindermann, Edward Bell, James Stratford, Davide Piffer
Intelligence (May-June 2014)


Highlights

o At the population-level IQ and Microcephalin correlate significantly (.790 and .847)

o Microcephalin significantly predicts population differences in IQ

o Microcephalin significantly predicts infectious disease burden

o Vice versa in the case of Microcephalin

o Microcephalin increased disease-resistance allowing access to new cognitive niches


Abstract 

Despite the fact that the recently evolved Microcephalin and the related Abnormal pindle-like Microcaphaly Associated (ASPM) alleles do not appear to be associated with IQ at the individual differences level, the frequencies of Microcephalin have been found to correlate strongly with IQ at the cross-country level. In this study, the association between these two alleles and intelligence is examined using a sample of 59 populations. A bivariate correlation between Microcephalin and population average IQ of r = .790 (p ≤ .01) was found, and a multiple regression analysis in which the Human Development Index, Disability Adjusted Life Years (DALY) lost due to Infectious diseases, DALY Nutritional deficiencies, and Würm glaciation temperature means were included revealed that Microcephalinremained a good predictor of IQ. Path analysis, with both direct and indirect paths from Microcephalin to intelligence, showed good model fit. These multivariate analyses revealed strong and robust associations between DALYs and Microcephalin, indicating that the former partially mediates the association between the latter and IQ. A second smaller correlational analysis involving ten country-level estimates of the frequencies of these two alleles collected from the 1000 genomes database replicated this pattern of results. To account for the findings of this study, we review evidence that these alleles are expressed in the immune system. Microcephalin is strongly associated with DNA repair, which indicates a special role for this allele in the intrinsic anti-viral immune response. Enhanced immune functioning may have advantaged both hunter–gatherer and agrarian societies coping with the heightened disease burden that resulted from population growth and exposure to zoonotic diseases, making it more likely that such growth and concomitant increases in intelligence could occur.

[Thanks @ Elijah]

Vocabulary for describing disliked persons is more differentiated than vocabulary for describing liked persons

Vocabulary for describing disliked persons is more differentiated than vocabulary for describing liked persons
Daniel Leising, Olga Ostrovski, Peter Borkenau
Journal of Research in Personality (2012)


Abstract

There is evidence that humans tend to differentiate more between negative stimuli than between positive stimuli. Our study investigated whether this applies to person descriptions. Participants (N = 168) generated their own terms for describing themselves and four others. Altogether, they generated 3319 terms, 758 of which were different from each other. The proportion of different terms was smaller in descriptions of liked targets (about 33%) than in descriptions of disliked targets (about 50%). Of the 758 different terms, about 60% had a negative valence, even though the perceivers were relatively fond of three of the five targets. We differentiate more between people we do not like, than between people we do like (including ourselves).

Dienstag, 1. April 2014

Personality and occupational markers of ‘solid citizenship’ are associated with having fewer children

Personality and occupational markers of ‘solid citizenship’ are associated with having fewer children
A. M. Perkins , R. Cserjesi, U. Ettinger, V. Kumari, N. G. Martin, R. Arden
Personality and Individual Differences (2013)


Abstract

Investigating associations between personality and reproductive fitness may reveal the adaptive significance of human behavioural traits. What we dub ‘solid-citizenship’ personality characteristics such as self-control, diligence and responsibility may repay study from an evolutionary perspective as they protect against negative life-outcomes. We explored associations between reproductive fitness and personality questionnaire markers of solid citizenship in 4981 women from four Australian samples. We also examined relations between reproductive fitness and army discharge status, an applied measure of solid citizenship, in 15,283 Vietnam War-era military veterans. In two Australian samples there were significant negative associations between reproductive fitness and personality measures of solid citizenship. Similarly, in the US study honourably discharged servicemen on average fathered significantly fewer children than non-honourably discharged servicemen. Since personality is genetically influenced, our results suggest that genetic variants for solid citizenship may be decreasing in frequency in some populations, in line with other modern findings but in contrast to historical analyses. Causes for this change may include relatively more conscientious women using contraception to prioritise their careers over reproduction and the availability of systematic welfare provisioning.

Against "consensus" science

>I often cringe when I hear the media use the word consensus in reference to some area of science. The concept of consensus is antithetical to the scientific method. I have no problem talking about "mainstream" or "conventional" science, or saying that "most scholars accept" some claim. But "consensus" is not right.

Much like the equally bad phrase "settled science," consensus implies that the debate is entirely over. That indisputable proof exists. That anyone who disagrees is simply wrong as a matter of objective fact. Worst of all, it implies that truth can be determined by a majority vote. ...<

Jason Richwine
[The whole article: Against "consensus" science (Feb 2014)]

Sex differences in the probability of consenting to sexual intercourse...





















Source:
Sex Differences - Developmental and Evolutionary Strategies
Linda Mealey (2000)
--------------------------------------------------------------------------------
Sexual strategies theory: an evolutionary perspective on human mating
D. Buss & D. P. Schmitt (1993)

Homicide rates by genetic versus stepfathers and by age of child for Canada.






















Source:
Sex Differences - Developmental and Evolutionary Strategies
Linda Mealey (2000)

Male-Female Suicide Ratio:

























Source:
Sex Differences - Developmental and Evolutionary Strategies
Linda Mealey (2000)