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Following the Developmental Theory of Sex Differences, males and females have roughly the same IQ during childhood. However, because females enter puberty earlier their general IQ exceeds that of males during early adolescence, after which males enter puberty. By their late teens, males have a small IQ advantage. To test this model, we administered the SPM+ to a sample of 701 male and 705 female school students aged 10 to 19 years from different schools in the Dhofar Governorate in the Sultanate of Oman. Our results broadly validated Lynn's model, as males scores exceeded those of females from the age of 16 onwards. However, we note that there are also alternative explanations for our findings.

Here we test the developmental theory of sex differences in intelligence using latent modeling. The theory has been recently updated ( Lynn, 2017 ). Based on men's greater average brain volumes and premature maturation in women, the theory predicts an intelligence advantage for women (or null sex differences) in early adolescence, but an advantage for men in late adolescence. The findings reported by Lynn are consistent with the theory, but basic measurement issues were not met. Are we taping the same construct regardless of sex and age and can we provide sound conclusions? We considered 10,335 individuals (4992 boys and 5343 girls) within an age range of 12–18 years. They completed the subtests included in the TEA Ability Battery (BAT-7). Theta scores for each subtest were estimated using a three-parameter logistic Item Response Theory model (3PL IRT). Results fitted properly to invariance criteria across age and sex. Latent estimates for the general factor of intelligence (g) were used for testing the theory. The observed findings were in agreement with the developmental theory: there were null sex differences at 12 years of age, but there was an average difference favoring boys equivalent to 5 IQ points at 18 years of age.

Scores of a sample of 2,440 male and female Somalian school students aged 8 through 18 years on the Standard Progressive Matrices Plus (SPM+) are reported. The sample obtained a British-scaled IQ of 68. There was no statistically significant difference between the scores of the males and females. The variance was greater among the females than among the males.

It is a paradox that males have a larger average brain size than females, that brain size is positively associated with intelligence, and yet numerous experts have asserted that there is no sex difference in intelligence. This paper presents the developmental theory of sex differences in intelligence as a solution to this problem. This states that boys and girls have about the same IQ up to the age of 15 years but from the age of 16 the average IQ of males becomes higher than that of females with an advantage increasing to approximately 4 IQ points in adulthood.

Richard Lynn’s developmental theory of sex differences in intelligence is evaluated using the administration of the Armed Services Vocational Aptitude Battery in the NLSY79. Score increases between age 15 and age 23 are found to be greater in males than in females, supporting an essential element of the theory. On the other hand, neither the sex differences themselves nor their developmental changes are related in any consistent way to the g loadings of the subtests. Therefore sex differences should not be conceptualized as differences in “general” intelligence (g).

Data for a sample of 18-year-old Applied Science and Social Science students in Libya are reported for intelligence (IQ), emotional intelligence (EI) and educational achievement. Means were significantly higher for Applied Science students than for Social Science students both for IQ and EI. Although males obtained higher means than females on intelligence assessed by the Standard Progressive Matrices, and females obtained higher means than males on emotional intelligence assessed by the Goleman test, the sex differences were very small and did not reach statistical significance. IQ, EI and educational achievement were significantly intercorrelated.

Few topics in psychology have generated as much controversy as sex differences in intelligence. For fluid intelligence, researchers emphasize the high overlap between the ability distributions of males and females, whereas research on sex differences in declarative knowledge often uncovers a male advantage. However, on the level of knowledge domains, a more nuanced picture emerged: while females perform better in health-related topics (e.g., aging, medicine), males outperform females in domains of natural sciences (e.g., engineering, physics). In this paper we show that sex differences vary substantially depending on item sampling. Analyses were based on a sample of n = 3306 German high-school students (Grades 9 and 10) who worked on the 64 declarative knowledge items of the Berlin Test of Fluid and Crystallized Intelligence (BEFKI) assessing knowledge within three broad content domains (science, humanities, social studies). Using two strategies of item sampling—stepwise confirmatory factor analysis and ant colony optimization algorithm—we deliberately manipulate sex differences in multi-group structural equation models. Results show that sex differences considerably vary depending on the indicators drawn from the item pool. Furthermore, ant colony optimization outperforms the simple stepwise selection strategy since it can optimize several criteria simultaneously (model fit, reliability, and preset sex differences). Taken together, studies reporting sex differences in declarative knowledge fail to acknowledge item sampling issues. On a more general stance, handling item sampling hinges on profound considerations of the content of measures.

The authors investigate sex differences in mean scores and variance, in general and specific intelligence, based on raw data from the standardization samples of six cognitive ability measures adapted and normed in Romania. The results show that fewer than 10% of the possible comparisons exhibit sex differences; these differences have a random pattern and are not replicated across measures. The authors conclude that these Romanian data show no support for the sex differences in either mean values or variance of scores which were reported by other studies.

Data are reported for the scores of men and women in the standardization of the American WAIS-IV. Men obtained a significantly higher Full Scale IQ than women by 2.25 IQ points and on the General Ability Index by 4.05 IQ points. Men obtained significantly higher scores on the index IQs of Verbal Comprehension, Perceptual Reasoning and Working Memory, and women obtained a significantly higher score on the Processing Speed index IQ. Men showed greater variability than women on the Full Scale IQ, the General Ability Index and on twelve of the fifteen subtests. Key Words: WAIS-IV, Sex differences, Intelligence, Variability

Considerable data are available about sex differences in intelligence, both at the general (more latent) and the specific (more explicit) levels, in children, adolescents, and adults. However, only a small proportion comes from developing countries, where socio-political conditions and patterns of sexual inequality differ markedly from those observed in developed countries. Comparing sex differences data in intelligence between cultures with contrasting socio-political backgrounds permits examining whether biological factors are behind such sex differences. In an effort towards addressing this, we reviewed and compiled intelligence data from Brazil, and found evidence for a male advantage in adulthood in most dimensions of intelligence. We then analyzed new adult data on three unidimensional IQ tests for the measurement of general intelligence (the g factor), and found evidence of a male advantage in two, but a female advantage in the third. However, scores on two tests appeared to be highly confounded with education level, and once this variable was controlled, the female advantage in one test and the male advantage in another were not noticeable.. In general, our results were mostly in line with the male advantage hypothesis, although this did not appear to be uniformly consistent or of high magnitude in Brazil. Societal implications are discussed. Key words: Intelligence, Sex differences, APM, Progressive Matrices, Brazil.

The relationship between sex and creativity remains an unresolved research question. The present study aimed to approach this question through the lens of the developmental theory of sex differences in intelligence, which posits a dynamic pattern of sex differences in intellectual abilities from female superiority in childhood and early adolescence to male superiority starting at 16 years of age. A total of 775 participants from three age groups (i.e., children, adolescents, and emerging adults) completed a 4-year longitudinal study comprising four assessments of creative thinking at 1-year intervals. Creative thinking was assessed with the Test for Creative Thinking-Drawing Production. While the results revealed female superiority in childhood and early adolescence, male superiority was not found in adolescence and emerging adulthood. Rather, greater sex similarities and greater male variability were found based on mean and variability analyses, respectively. This study elucidated the link between sex and creativity by (1) taking a developmental perspective, (2) employing a 4-year longitudinal design in three age groups (i.e., children, adolescents, and emerging adults), and (3) analyzing sex differences based on both mean and variability analyses.

This study focuses on lay conceptions of intelligence. It examined sex and cross-cultural similarities and differences in estimated intelligences and beliefs about intelligence in two countries, Angola and East Timor, within the reversal theory framework. A total of 209 Angolan (109 women and 100 men) and 183 Timorese (89 women and 94 men) students were participated in this study. Participants completed a questionnaire in order to estimate their parents', partners' and own overall intelligence and the 8 reversal multiple intelligences (telic, paratelic, conformist, negativistic, autic mastery, autic sympathy, alloic mastery and alloic sympathy intelligence). Respondents also rated 6 questions about intelligence. Men rated their overall, conformist and autic mastery higher than women. Angolans rated their overall, telic, paratelic, conformist, negativistic, autic mastery, autic sympathy, alloic mastery and alloic sympathy intelligence higher than Timorese. In both countries, fathers have been perceived as more intelligent than mothers, and telic intelligence emerged as a significant predictor of overall intelligence. Principal component analysis of the 8 reversal multiple intelligences yielded one factor. Angolan participants revealed more IQ test experience than Timorese participants. Most of respondents in both countries did not believe in sex differences in intelligence. These findings are discussed by means of cross-cultural literature.

A study of sex differences in the intelligence of university students in Thailand tested with the Advanced Progressive Matrices found that men obtained a slightly higher score than women by .08d equivalent to 1.2 IQ points. The sample obtained a British IQ of 103. Key Words: Thailand, Advanced Progressive Matrices, Sex differences, Intelligence

Studies reporting sex differences in intelligence among the Swedish adult population were systematically reviewed. Five studies from 1959 to 2008 fulfilled the inclusion criteria, and were suppleme ...