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The g Factor: The Science of Mental Ability

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Abstract

A pesar de la relativamente corta historia de la Psicología como ciencia, existen pocos constructos psicológicos que perduren 90 años después de su formulación y que, aún más, continúen plenamente vigentes en la actualidad. El factor «g» es sin duda alguna uno de esos escasos ejemplos y para contrastar su vigencia actual tan sólo hace falta comprobar su lugar de preeminencia en los modelos factoriales de la inteligencia más aceptados en la actualidad, bien como un factor de tercer orden en los modelos jerárquicos o bien identificado con un factor de segundo orden en el modelo del recientemente desaparecido R.B.Cattell.

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... a. Relevanz der allgemeinen Intelligenz g für Schul, Aus bildungs, Studien und Berufserfolg;vgl. Gott fredson, 1997;Jensen, 1998;Rost, 2013) spre chen auch diagnostische Argumente für eine intelligenzbasierte, eindimensionale Konzep tion intellektueller Hochbegabung: So liegen einige zur Hochbegabungsdiagnostik im Kin des und Jugendalter gut geeignete Intelligenz tests mit in der Regel als mindestens gut zu be wertenden Gütekriterien vor (vgl. z. ...
... Dies gilt in ähnlicher Form für beispielsweise den Gruppenfaktor reasoning (im Sinne des CattellHornCarroll Modells; McGrew, 2009) oder einen in bei den Tests vergleichbar zusammengesetzten In telligenzGeneralfaktor g (z. B. Jensen, 1998;Rost, 2013 (Lukesch, Kormann & Mayrhofer, 2002) und der Kurzform des ausschließlich Aufgaben zum figuralen reasoning umfassenden CFT 20R (Weiß, 2006). Außerdem korrelierten HAWIK IV (Daseking, Petermann & Petermann, 2007) und IDS (Grob, Meyer & Hagmannvon Arx, 2009) in einer Begabten und Normalbe gabtenstichprobe (jeweils N = 77 Sechs bis Zehnjährige) zu r = .73 in der Normalbegabten stichprobe bzw. ...
... Dieser Intelligenzfaktor bildet nicht das ge samte Intelligenztestspektrum oder einen In telligenzgeneralfaktor im Sinne eines "guten g" (Jensen & Weng, 1994) ab; diese Aufgaben arten laden jedoch hoch auf dem Intelligenz Generalfaktor und ermöglichen somit eine gu te Abschätzung der allgemeinen Intelligenz (z. B. Jensen, 1998 ...
... Geneticists have identified specific genetic variants correlated with neurodevelopment and brain functioning that are also associated with interindividual differences in intelligence or educational attainment (e.g., Adams et al., 2016;Lee et al., 2018;Okbay et al., 2016). Likewise, intelligence differences have been shown to correlate with many important health, occupational, educational, and psychosocial outcomes (Gottfredson, 1997b;Jensen, 1998;Warne, 2016a), many of which intelligence tests were never designed to predict, such as longevity (Arden et al., 2016;Gottfredson & Deary, 2004). ...
... However, if Spearman's hypothesis is true, then it would indicate that within-and between-group differences in intelligence arise from many of the same sources (genes and environment) because the sources of within-and between-group variation are positively correlated and share variance with one another. This finding would be consistent with the belief that group mean differences in intelligence are mostly (or perhaps entirely) the product of the accumulation of individual differences (Jensen, 1998;Rushton & Jensen, 2005). Moreover, it would indicate that any unique environmental influences that operate on one group would be trivial in their impact on betweengroup differences. ...
... This shortcoming arises because the method does not detect violations of statistical assumptions that must be met in order to justify such conclusions (Dolan & Hamaker, 2001;Lubke, Dolan, & Kelderman, 2001;Wicherts, 2017). Additionally, MCV results are sensitive to subjective decisions about data preparation, such as the selection of subtests used to identify a g factor (Ashton & Lee, 2005), although collecting scores from a wide variety of subtest formats generally solves this problem (Jensen, 1992(Jensen, , 1998. Some statistical corrections are available to adjust for the restriction of range that can develop from a narrow selection of subtests (te Nijenhuis et al., 2019), although these rely on assumptions that may be difficult to prove. ...
Article
The past 30 years of research in intelligence has produced a wealth of knowledge about the causes and consequences of differences in intelligence between individuals, and today mainstream opinion is that individual differences in intelligence are caused by both genetic and environmental influences. Much more contentious is the discussion over the cause of mean intelligence differences between racial or ethnic groups. In contrast to the general consensus that interindividual differences are both genetic and environmental in origin, some claim that mean intelligence differences between racial groups are completely environmental in origin, whereas others postulate a mix of genetic and environmental causes. In this article I discuss 5 lines of research that provide evidence that mean differences in intelligence between racial and ethnic groups are partially genetic. These lines of evidence are findings in support of Spearman’s hypothesis, consistent results from tests of measurement invariance across American racial groups, the mathematical relationship that exists for between-group and within-group sources of heritability, genomic data derived from genome-wide association studies of intelligence and polygenic scores applied to diverse samples, and admixture studies. I also discuss future potential lines of evidence regarding the causes of average group differences across racial groups. However, the data are not fully conclusive, and the exact degree to which genes influence intergroup mean differences in intelligence is not known. This discussion applies only to native English speakers born in the United States and not necessarily to any other human populations.
... Key Words: Intelligence, Fertility, Oman, Dysgenics Scores on IQ tests are the best predictor of school performance and work performance, which are essential for economic prosperity (Jensen, 1998). Substantial rises in IQ (the "Flynn effect") made rapid economic growth possible in Western countries during the 20 th century; and conversely, declines in the mean IQ of the population are a threat to economic development and are, therefore, a serious concern. ...
... In addition, negative correlations of robust proxies for intelligence, such as education level or socioeconomic status (see Jensen, 1998), with fertility or family size have been documented in many countries including the Netherlands, Japan, Norway, Ireland, Portugal, Sweden, France, Hungary, and Poland (see Lynn, 1996). The present study contributes to this research by empirically testing whether these small negative relationships also exist in the Sultanate of Oman, an Arab nation of roughly 4 million, of which 1.75 million are expatriate workers rather than Omanis. ...
... The items are arranged in order of increasing difficulty. The total score provides a sound measure of the general factor of intelligence (g) (Jensen, 1998). ...
Article
Many studies have shown a small negative correlation between intelligence and fertility in developed countries. Several studies have provided evidence of a similar relationship in developing countries, notably in several Arab nations. The present study contributes to this body of research by testing whether this small negative relationship also exists in a poor region of the Sultanate of Oman, thus contributing to the important issue of understanding whether intelligence is in decline beyond the West even in poorer areas. The study used a sample of 1406 students aged 10 to 19 years from schools in the Dhofar Governorate in Oman. The correlations between children’s IQ and family size and between parents’ education and family size were computed, with parent education being a robust proxy for intelligence. This yielded a small negative relationship between children’s IQ and their family size, and a moderate-sized negative relationship between parental education and family size. It is concluded that there is a negative relationship between education and fertility in Oman and that this suggests a small negative relationship between parents’ intelligence and the number of their children. These data suggest that at the genetic level, intelligence is slowly declining in the Arab world although test scores are still rising due to educational and economic advances.
... Key Words: Intelligence, Fertility, Oman, Dysgenics Scores on IQ tests are the best predictor of school performance and work performance, which are essential for economic prosperity (Jensen, 1998). Substantial rises in IQ (the "Flynn effect") made rapid economic growth possible in Western countries during the 20 th century; and conversely, declines in the mean IQ of the population are a threat to economic development and are, therefore, a serious concern. ...
... In addition, negative correlations of robust proxies for intelligence, such as education level or socioeconomic status (see Jensen, 1998), with fertility or family size have been documented in many countries including the Netherlands, Japan, Norway, Ireland, Portugal, Sweden, France, Hungary, and Poland (see Lynn, 1996). The present study contributes to this research by empirically testing whether these small negative relationships also exist in the Sultanate of Oman, an Arab nation of roughly 4 million, of which 1.75 million are expatriate workers rather than Omanis. ...
... The items are arranged in order of increasing difficulty. The total score provides a sound measure of the general factor of intelligence (g) (Jensen, 1998). ...
Article
Full-text available
Many studies have shown a small negative correlation between intelligence and fertility in developed countries. Several studies have provided evidence of a similar relationship in developing countries, notably in several Arab nations. The present study contributes to this body of research by testing whether this small negative relationship also exists in a poor region of the Sultanate of Oman, thus contributing to the important issue of understanding whether intelligence is in decline beyond the West even in poorer areas. The study used a sample of 1406 students aged 10 to 19 years from schools in the Dhofar Governorate in Oman. The correlations between children’s IQ and family size and between parents’ education and family size were computed, with parent education being a robust proxy for intelligence. This yielded a small negative relationship between children’s IQ and their family size, and a moderate-sized negative relationship between parental education and family size. It is concluded that there is a negative relationship between education and fertility in Oman and that this suggests a small negative relationship between parents’ intelligence and the number of their children. These data suggest that at the genetic level, intelligence is slowly declining in the Arab world although test scores are still rising due to educational and economic advances.
... In Sweden, for example, being a middle-aged childless man is correlated with alcoholism but the precise direction of the relationship is unclear (Hadley, 2019, p.53). Alcoholism is negatively correlated with IQ (Jensen, 1998). ...
... The scores are highly correlated in practice (r = 0.87 in this study). We used the mirt package to extract a single factor from the 10 items, which we took as a proxy for general intelligence (the g factor; Jensen, 1998). All loadings were positive, see R notebook output for details. ...
... Practicing Latter-day Saints are expected not only to tithe but to devote an enormous amount of their free time to aiding their church. This would, in effect, act to select out less intelligent Latterday Saints via the associations between intelligence and future-orientation, altruism, community-orientation, and depth of interests (Eisenberg-Berg, 1979;Jensen, 1998;Jones, 2008). ...
Article
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There is solid evidence that human populations have been selecting against intelligence-related genetic variants since the mid to late 1800s. The selection is generally weak, but varies by ethnic group and sex. Since religious teachings usually include strong pro-natalist components, we investigated whether this might also affect the selection for intelligence among different religious groups. We found that Latter-day Saints in the USA show slightly positive selection for intelligence, whereas all other religious groups examined did not robustly differ from the average. We similarly found that conservatives, in general, show a weaker selection against intelligence than do liberals.
... Together with these personality factors, cognitive intelligence emerges as the strongest predictor of academic achievement. As Jensen (1998) pointed out, if there is any unquestionable fact in applied psychometry, it is that cognitive intelligence tests have an unequivocal high degree of predictive validity for many educational criteria such as school and college grades, graduating on time, the probability of entering college and, after entering, the probability of receiving a bachelor's degree. Broadly, cognitive intelligence refers to the fundamental ability to reason (Cattell, 1943;Carroll, 1993;Jensen, 1998). ...
... As Jensen (1998) pointed out, if there is any unquestionable fact in applied psychometry, it is that cognitive intelligence tests have an unequivocal high degree of predictive validity for many educational criteria such as school and college grades, graduating on time, the probability of entering college and, after entering, the probability of receiving a bachelor's degree. Broadly, cognitive intelligence refers to the fundamental ability to reason (Cattell, 1943;Carroll, 1993;Jensen, 1998). Those high in cognitive intelligence do not only assimilate training better, but also learn more effectively from experience. ...
... In accordance with its involvement in cognitive functions, the human PC has been found to play a role in g (both structurally and functionally, see Menary et al., 2013;Basten et al., 2015;Hilger et al., 2017;Takeuchi et al., 2018). The construct of g, which is best conceptualized as "a distillate obtained from many diverse abilities" (Jensen, 1998), is regarded as the single best predictor of scholastic and vocational achievements as well as other socially relevant outcomes (Gottfredson, 1997;Jensen, 1998). Due to its association with neurological variables (Penke et al., 2012;Gignac and Bates, 2017), g has become a major focus of investigation (Haier, 2016), and the influential "Parieto-Frontal Integration Theory" (Jung and Haier, 2007) posits that g is closely related to a task-invariant network comprising a circumscribed set of brain regions. ...
... In accordance with its involvement in cognitive functions, the human PC has been found to play a role in g (both structurally and functionally, see Menary et al., 2013;Basten et al., 2015;Hilger et al., 2017;Takeuchi et al., 2018). The construct of g, which is best conceptualized as "a distillate obtained from many diverse abilities" (Jensen, 1998), is regarded as the single best predictor of scholastic and vocational achievements as well as other socially relevant outcomes (Gottfredson, 1997;Jensen, 1998). Due to its association with neurological variables (Penke et al., 2012;Gignac and Bates, 2017), g has become a major focus of investigation (Haier, 2016), and the influential "Parieto-Frontal Integration Theory" (Jung and Haier, 2007) posits that g is closely related to a task-invariant network comprising a circumscribed set of brain regions. ...
Article
Full-text available
The human posteromedial cortex (PMC), which includes the precuneus (PC), represents a multimodal brain area implicated in emotion, conscious awareness, spatial cognition, and social behavior. Here, we describe the presence of Nissl-stained elongated spindle-shaped neurons (suggestive of von Economo neurons, VENs) in the cortical layer V of the anterior and central PC of adult humans. The adapted "single-section" Golgi method for postmortem tissue was used to study these neurons close to pyramidal ones in layer V until merging with layer VI polymorphic cells. From three-dimensional (3D) reconstructed images, we describe the cell body, two main longitudinally oriented ascending and descending dendrites as well as the occurrence of spines from proximal to distal segments. The primary dendritic shafts give rise to thin collateral branches with a radial orientation, and pleomorphic spines were observed with a sparse to moderate density along the dendritic length. Other spindle-shaped cells were observed with straight dendritic shafts and rare branches or with an axon emerging from the soma. We discuss the morphology of these cells and those considered VENs in cortical areas forming integrated brain networks for higher-order activities. The presence of spindle-shaped neurons and the current discussion on the morphology of putative VENs address the need for an in-depth neurochemical and transcriptomic characterization of the PC cytoarchitecture. These findings would include these spindle-shaped cells in the synaptic and information processing by the default mode network and for general intelligence in healthy individuals and in neuropsychiatric disorders involving the PC in the context of the PMC functioning.
... He used the term "positive manifold" to refer to the existence of g as representing the portion of variance that existing intelligence tests have in common, proposing that people who score well on one cognitive task are likely to do well in others. Since then, the psychometric g has been used as an index or a score factor derived from cognitive tests, standing for a latent variable-a sum total of an individual's scores (Scarr, 1997;Jensen, 1998Jensen, , 2002. Cattell (1943Cattell ( , 1971) and Horn (Cattell and Horn, 1978) analyzed the nature of g by breaking it down into two major cognitive constructs, namely fluid (gf ) and crystallized intelligence (gc). ...
... In this hierarchy, the top stratum, conceptually equivalent to Spearman's g, strongly correlates with eight factors placed at the second level that are differentially influenced by g. These broad abilities, similar to Cattell and Horn's theory, include fluid intelligence (gf ), crystallized intelligence (gc), analogical reasoning, and working memory, which are then broken down into a number of specific abilities within the third stratum (see also Horn and Cattell, 1966;Jensen, 1998;Deary, 2001;Carroll, 2003;Sternberg, 2003). ...
Article
Full-text available
To what extent general intelligence mechanisms are associated with causal thinking is unclear. There has been little work done experimentally to determine which developing cognitive capacities help to integrate causal knowledge into explicit systems. To investigate this neglected aspect of development, 138 children aged 5–11 studying at mainstream primary schools completed a battery of three intelligence tests: one investigating verbal ability (WASI vocabulary), another looking at verbal analogical (Verbal Analogies subset of the WRIT), and a third assessing non-verbal/fluid reasoning (WASI block design). Children were also interviewed over the course of three causal tasks (sinking, absorption, and solution), with the results showing that the developmental paths exhibited uneven profiles across the three causal phenomena. Children consistently found that explaining solution, where substances disappeared toward the end of the process, was more challenging. The confirmatory factor analyses suggested that the impact of cognitive ability factor in explicitly identifying causal relations was large. The proportion of the direct effect of general intelligence was 66% and it subsumed the variances of both verbal measures. Of this, 37% was the indirect effect of age. Fluid reasoning explained a further 28% of the variance, playing a unique role in causal explanation. The results suggested that, overall, cognitive abilities are substantially related to causal reasoning, but not entirely due to developmental differences in “g” during the age periods studied.
... Together with these personality factors, cognitive intelligence emerges as the strongest predictor of academic achievement. As Jensen (1998) pointed out, if there is any unquestionable fact in applied psychometry, it is that cognitive intelligence tests have an unequivocal high degree of predictive validity for many educational criteria such as school and college grades, graduating on time, the probability of entering college and, after entering, the probability of receiving a bachelor's degree. Broadly, cognitive intelligence refers to the fundamental ability to reason (Cattell, 1943;Carroll, 1993;Jensen, 1998). ...
... As Jensen (1998) pointed out, if there is any unquestionable fact in applied psychometry, it is that cognitive intelligence tests have an unequivocal high degree of predictive validity for many educational criteria such as school and college grades, graduating on time, the probability of entering college and, after entering, the probability of receiving a bachelor's degree. Broadly, cognitive intelligence refers to the fundamental ability to reason (Cattell, 1943;Carroll, 1993;Jensen, 1998). Those high in cognitive intelligence do not only assimilate training better, but also learn more effectively from experience. ...
Article
Full-text available
Counterproductive academic behaviors (CAB) are a complex phenomenon that affects academic institutions in multiple geographical areas with different cultures, values, and social norms. The high incidence of CAB causes problems of critical importance that transcend the educational domain. The current study aims to contribute to the knowledge of the CAB consequences by focusing on its impact on academic performance (AP). For this purpose, a meta-analysis was conducted in order to examine the relationship between CAB, its facets, and AP. The results show that overall CAB and students' performance are negatively related with a true effect size of ρ = −0.40 (K = 231, N = 127,269). Particularly, absenteeism appeared to be the facet most strongly related to AP (ρ = −0.48, K = 117, N = 69,453). A meta-analytic path analysis model was carried out in order to test the predictive validity of CAB, students' personality characteristics, and intelligence on AP. Results show that conscientiousness and cognitive intelligence have a negative relationship with CAB (β = −0.28 and β = −0.20, respectively), and that conscientiousness, openness to experience, intelligence, and CAB can explain 58% of AP true variance. Meta-analyses of moderator variables and hierarchical meta-analyses are also presented. The implications for research and practice are discussed at the end.
... 1 And only 3 years later, he replicated the finding with respect to 13 additional nations (Flynn, 1987). After this, the apparently ubiquitous secular increase in IQ scores gained widespread attention, and it eventually became known as the "Flynn effect"-a term coined by Herrnstein and Murray (1994, p. 307). 2 The Flynn effect certainly provides prima facie evidence for an affirmative answer to the question with which this article began, especially given the fact that the IQ tests on which the Flynn effect have been observed are both (typically) highly g loaded and highly correlated with real world outcomes that are antecedently known to draw upon important intellectual abilities, such as job performance and educational attainment (Deary, Strand, Smith, & Fernandes, 2007;Jensen, 1998;Schmidt & Hunter, 1999). However, despite massive accumulating data demonstrating a Flynn effect of approximately 3 IQ points per decade in countries from all around the world Trahan, Stuebing, Fletcher, & Hiscock, 2014), intelligence researchers have often been skeptical of the claim that the increase in IQ scores during the 20th century reflects a genuine improvement in intellectual ability. ...
... According to the co-occurrence model, the paradox in question is resolved by the proposition that the average person in 1900 had a higher, rather than lower level of g compared to the average person today. Moreover, since g is correlated to a much larger extent than s.e with other socially valued traits and real-world outcomes (Ackerman, Kanfer, & Calderwood, 2013;Jensen, 1998;Kell, Lubinski, Benbow, & Steiger, 2013;Zaboski, Kranzler, & Gage, 2018), it follows that the people living in 1900 cannot meaningfully be said to be intellectually disabled compared to contemporary populations. In fact, given what we now know about the prevalence and magnitude of the Woodley effect (based on both genetic and phenotypic indicators, losses in the range of half an IQ point per decade can be expected), a more puzzling question is why contemporary populations still are so scientifically and technologically advanced, despite the drop in g. ...
Article
Full-text available
This paper discusses the co-occurrence model and its associated research program, and it argues that the model provides the best supported theory of secular changes in cognitive ability. The co-occurrence model offers a better solution to Cattell's paradox (relative to the alternatives in the literature), and it is able to accommodate Flynn's four major paradoxes also. A review of empirical work conducted in order to test the model's predictions demonstrates that many populations in which selection favors lower intelligence have experienced a decline in g or some cognitive ability variable that correlates with g, at the same time that average phenotypic IQ has increased. Moreover, since the co-occurrence model makes predictions about variables that are not directly concerned with cognitive ability testing, its research program can be extended to other domains of research.
... The cognitive explanation is that participants vary with respect to how fast simple operations can be executed. Quicker participants can process information in working memory faster and therefore can process more information before it has decayed (Jensen, 1998). The reductionist explanation regards processing speed as an indicator of a neural variable that is responsible for intelligence, such as nerve conduction velocity (Vernon and Mori, 1992), string length (Hendrickson and Hendrickson, 1980), white matter integrity (Deary et al., 2006), inferred parieto-frontal integration of information transmission and many more candidates. ...
... 1. the positive manifold of performance differences in cognitive tasks (Jensen, 1998;Spearman, 1904) 2. The structure in the correlation matrix, with clusters of tasks that correlate more strongly with each other than with tasks outside of the cluster (Beauducel, Brocke, and Liepmann, 2001;McGrew, 2005;Süß and Beauducel, 2005), which underlies the group-level factors for specific content domains (e.g., verbal, spatial) and classes of tasks (e.g., speed, reasoning). In other words, the correlation between any two intelligence tasks varies as a function of task attributes. ...
Article
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Despite over a century of research on intelligence, the cognitive processes underlying intelligent behavior are still unclear. In this review, we summarize empirical results investigating the contribution of cognitive processes associated with working memory capacity, processing speed, and executive processes to intelligence differences. Specifically, we (a) evaluate how cognitive processes associated with the three different cognitive domains have been measured, and (b) how these processes are related to individual differences in intelligence. Consistently, this review illustrates that isolating single cognitive processes using average performance in cognitive tasks is hardly possible. Instead, formal models that implement theories of cognitive processes underlying performance in different cognitive tasks may provide more adequate indicators of single cognitive processes. Therefore, we outlined which models for working memory capacity, processing speed, and executive processes may provide more specific insights into cognitive processes associated with individual differences in intelligence. Finally, we discuss implications of a process-oriented intelligence research using cognitive measurement models for psy-chometric theories of intelligence and argue that a model-based approach might overcome validity problems of traditional intelligence theories.
... Yet, empirical studies have repeatedly shown how difficult it is to pinpoint the exact contributions of intellectual capacities, practice, and previous knowledge in academic performance. Intellectual capacities, commonly measured by intelligence tests, lose their impact on academic performance as pupils move from middle school to high school (Neisser et al., 1996), and then on to college (Jensen, 1998;Poropat, 2009;Wachs & Harris, 1986). Practice, measured as effort-related activities, is often not a significant predictor of academic performance at all (Rau & Durand, 2000;Schuman et al., 1985). ...
... Its predictive power, however, weakens at college level, where it is either a smaller factor (Jensen, 1998;Poropat, 2009;Roberts et al., 1978) or not a significant contributor to academic success in any way (Wachs & Harris, 1986). Unlike primary and secondary education, which most people will complete, only a select cohort, often based on intelligence as much on their previous academic success, will go to college. ...
Article
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It is well established that academic performance (AP) depends on a number of factors, such as intellectual capacities, practice, and previous knowledge. We know little about how these factors interact as they are rarely measured simultaneously. Here we present mediated-Factors of Academic Performance (m-FAP) model, which simultaneously assesses direct and indirect, mediated, effects on AP. In a semester-long study with 118 first-year college students, we show that intelligence and working memory only indirectly influenced AP on a familiar, less challenging college course (Introduction to Psychology). Their influence was mediated through previous knowledge and self-regulated learning activities akin to deliberate practice. In a novel and more challenging course (Statistics in Psychology), intellectual capacities influenced performance both directly and indirectly through previous knowledge. The influence of deliberate practice, however, was considerably weaker in the novel course. The amount of time and effort that the students spent on the more difficult course could not offset the advantage of their more intelligent and more knowledgeable peers. The m–FAP model explains previous contradictory results by providing a framework for understanding the extent and limitations of individual factors in AP, which depend not only on each other, but also on the learning context.
... The measure was developed for ages 5-11, and since then it has been subject to several validation studies among English-speaking or international participants, which have produced strong evidence for its construct (Facon et al. 2011;Goharpey et al. 2013;Van Herwegen et al. 2011) and discriminant validity, such as when demonstrating cognitive dysfunction in cerebral palsy (Pueyo et al. 2008). The matrices have been normed in over 35 countries and are now considered to be one of the most valid measures of g (Jensen 1998) or general intelligence (Abad et al. 2004;Mackintosh 1996), especially as a culture-free measure. Interestingly, a Google search reveals 6,820,000 pages for CPM and google scholar shows 23,400 empirical studies, verifying their wide implementation and use. ...
Article
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Abstract: The purpose of the present study was to evaluate the psychometric properties of Raven’s colored progressive matrices by estimating the presence of pseudo-guessing and pseudo-carelessness. Participants were 1127 children from ages 5 to 11. Guessing and carelessness were assessed using the lower and upper asymptotes of the 3PL and 4PL item response theory (IRT) models, respectively. Optimal model fit was judged using difference loglikelihood tests and information criteria. Results indicated that guessing, but not carelessness, were evident in the AB and B forms of the CPM, with successful guessing being more prevalent in the AB form. It is concluded that nonverbal IQ estimation in CPM should include variable estimation methods so that aptitude scores are estimated with the highest possible accuracy.
... Fourth, state-level aggregation produces large effect sizes. For example, the individual-level correlation between income and IQ is around .30 (Jensen, 1998). Here it is .71. ...
Preprint
At the level of the 50 U.S. states, an interconnected nexus of well-being variables exists. These variables have been shown to strongly correlate with estimates of state IQ in interesting ways. But the state IQ estimates (McDaniel 2006) are now more than 16 years old, and the state well-being estimates (Pesta et al., 2010) are over 12 years old. Updated state IQ and well-being estimates are therefore needed. I thus first created new state IQ estimates by analyzing scores from both the Program for the International Assessment of Adult Competency (for adults), and the National Assessment of Educational Progress (for fourth and eighth grade children) exams. I also created new global well-being scores by analyzing state variables from the following four well-being subdomains: crime, income, health, and education. When validating the nexus, several interesting correlations existed among the variables. For example, state IQ most strongly predicted FICO credit scores, alcohol consumption (directly), income inequality, and state temperature. Interestingly, state IQ derived here also correlated .58 with state IQ estimates from over 100 years ago. Global well-being likewise correlated with many old and new variables in the nexus, including a correlation of .80 with IQ. In sum, at the level of the U.S. state, a nexus of important, strongly correlated variables exists. These variables comprise well-being, and state IQ is a central node in this network.
... Fourth, state-level aggregation produces large effect sizes. For example, the individuallevel correlation between income and IQ is around 0.30 (Jensen 1998). Here, it is 0.71. ...
Article
Full-text available
At the level of the 50 U.S. states, an interconnected nexus of well-being variables exists. These variables strongly correlate with estimates of state IQ in interesting ways. However, the state IQ estimates are now more than 16 years old, and the state well-being estimates are over 12 years old. Updated state IQ and well-being estimates are therefore needed. Thus, I first created new state IQ estimates by analyzing scores from both the Program for the International Assessment of Adult Competency (for adults), and the National Assessment of Educational Progress (for fourth and eighth grade children) exams. I also created new global well-being scores by analyzing state variables from the following four well-being subdomains: crime, income, health, and education. When validating the nexus, several interesting correlations existed among the variables. For example, state IQ most strongly predicted FICO credit scores, alcohol consumption (directly), income inequality, and state temperature. Interestingly, state IQ derived here also correlated 0.58 with state IQ estimates from over 100 years ago. Global well-being likewise correlated with many old and new variables in the nexus, including a correlation of 0.80 with IQ. In sum, at the level of the U.S. state, a nexus of important, strongly correlated variables exists. These variables comprise well-being, and state IQ is a central node in this network.
... Previous research showed that a single factor can be found in the taxonomies of cognitive abilities (Carroll, 1993), psychopathological symptoms (Lahey et al., 2012) and personality traits . Furthermore, empirical research showed that General factors are quite robust in all these three domains of human individual differences (Jensen, 1998;Rushton & Irwing, 2009a, b, c, d;Smith et al., 2020). Is there a General Factor of Social Attitudes? ...
Article
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Previous studies showed the existence of general factors in cognitive abilities, personality traits, and psychopathology symptoms. We hypothesized a similar factor on the apex of social attitudes' hierarchy; furthermore, we assumed that this factor reflects a conservatism-liberalism dimension. This hypothesis is tested by factorizing the space of "isms": a broad and comprehensive model of social attitudes obtained by the lexical paradigm, in an online study (N = 380; Mage = 32.34[SD = 11.74]; 66.8% females; participants were of Serbian nationality). A General factor is obtained and it was positively loaded by Tradition-oriented Religiousness (.76), Unmitigated Self-Interest (.76), and Subjective Spirituality (.34), with negative loadings of Communal Rationalism (-.53) and Inequality Aversion (-.46). Afterwards, we explored the nomological network of this factor: it correlated positively with the Social Dominance Orientation measure of Social Domination, Social Conservatism, Conservation Values, and Binding Moral Foundations; it also had negative associations with the Social Dominance Orientation measure of Egalitarianism, Self-transcendence Values, Individualizing Moral Foundations, Openness to Experience, Support for EU Integrations, Kosovo Independence, and Immigrants' Integration. The obtained nomological network is congruent with the interpretation of the General factor as conservatism. The data suggest that lay people have a singular core attitudinal dimension which they use to interpret and make sense of societal events and this fundamental dimension is conservatism-liberalism.
... Figural matrices tasks represent a well-established class of tasks in intelligence tests that load highly on general intelligence (Carpenter et al. 1990;Jensen 1998;Marshalek et al. 1983) or, more specifically, on fluid reasoning (Gignac 2015) and are part of many broad intelligence test batteries (e.g., Wechsler 2008). Fluid reasoning is an integral part of modern intelligence models (Carroll 1993;McGrew 2005McGrew , 2009 and has a decisive role in many aspects of a human's life, such as occupational success (Schmidt and Hunter 2016), educational attainment (Roth et al. 2015), and health (Gottfredson and Deary 2004). ...
Article
Figural matrices tasks are one of the most prominent item formats used in intelligence tests, and their relevance for the assessment of cognitive abilities is unquestionable. However, despite endeavors of the open science movement to make scientific research accessible on all levels, there is a lack of royalty-free figural matrices tests. The Open Matrices Item Bank (OMIB) closes this gap by providing free and unlimited access (GPLv3 license) to a large set of empirically validated figural matrices items. We developed a set of 220 figural matrices based on well-established construction principles commonly used in matrices tests and administered them to a sample of N = 2572 applicants to medical schools. The results of item response models and reliability analyses demonstrate the excellent psychometric properties of the items. In the discussion, we elucidate how researchers can already use the OMIB to gain access to high-quality matrices tests for their studies. Furthermore, we provide perspectives for features that could additionally improve the utility of the OMIB.
... Another concern is that ability was measured as part of wave I, and hence could be determined simultaneously with students' ranks. Yet, evidence in the literature indicates that crystallized intelligence-as measured by the PPVT-R-is only malleable early in life and is considered stable from age 10 onward (Jensen, 1998). At the time of AddHealth's wave I, when students were on average 15.6 years old, our measure of cognitive ability can therefore be seen as predetermined and unaffected by features of the school environment and the students' own or their parents' investments. ...
Article
This paper studies how peers in school affect students’ mental health. Guided by a theoretical framework, we find that increasing students’ relative ranks in their cohorts by one standard deviation improves their mental health by 6% of a standard deviation conditional on own ability. These effects are more pronounced for low-ability students, persistent for at least 14 years, and carry over to economic long-run outcomes. Moreover, we document a pronounced asymmetry: Students who receive negative rather than positive shocks react more strongly. Our findings therefore provide evidence on how the school environment can have long-lasting consequences for individuals’ well-being.
... Ezek alapján kirajzolódnak speciális képességeket megjelenítő faktorok, amelyek a specifikus tesztek egymással való szorosabb korrelációjából származnak, és egy általános faktor, amely minden teszt minden mással való pozitív korrelációjának eredménye. Ez utóbbit g-faktornak nevezik, a general (általános) kezdőbetűje nyomán (Jensen, 1998;Spearman, 1904). Az intelligencia szerkezetéről szóló faktoranalitikus vizsgálatokból különböző képességmodellek születtek. ...
... D is conceptualized as the underlying disposition or common core of aversive traits in the same way as Spearman's g factor of intelligence represents the shared basis of mental abilities (Jensen, 1998). By this logic, D is the general tendency from which all aversive traits essentially arise as specific, flavored manifestations , in turn predicting diverse behaviors that represent utility maximization at others' expense Moshagen, Zettler, Horsten, et al., 2020;Zettler et al., 2022). ...
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Whereas research focusing on stable dispositions has long attributed ethically and socially aversive behavior to an array of aversive (or ‘dark’) traits, other approaches from social-cognitive psychology and behavioral economics have emphasized the crucial role of social norms and situational justifications that allow individuals to uphold a positive self-image despite their harmful actions. We bridge these research traditions by focusing on the common core of aversive traits (the dark factor of personality, D) and its defining aspect of involving diverse beliefs that serve to construct justifications. In particular, we theoretically specify the processes by which D is expressed in aversive behavior – namely, through diverse beliefs and the justifications they serve. In 6 studies (total N > 25,000) we demonstrate (i) that D involves higher subjective justifiability of those aversive behaviors that individuals high in D are more likely to engage in, (ii) that D uniquely relates to diverse descriptive and injunctive beliefs – related to distrust (e.g. cynicism), hierarchy (e.g. authoritarianism), and relativism (e.g. normlessness) – that serve to justify aversive behavior, and (iii) a theoretically derived pattern of moderations and mediations supporting the view that D accounts for aversive behavior because it fosters subjective justifiability thereof – at least in part due to certain beliefs and the justifications they afford. More generally, our findings highlight the role of (social) cognitions within the conceptual definitions of personality traits and processes through which they are expressed in behavior.
... A good indicator of the presence of general intelligence in humans is the psychometric factor g. g results from the positive manifold, i.e. the well-established finding that, in humans, individual performance across tasks testing different domains is correlated (Carroll, 1993;Deary et al., 2010;Jensen, 1999;Jensen & Weng, 1994;Nisbett et al., 2012;Spearman, 1904). Factor analyses of performance across such tasks will thus result in a first factor on which all tasks load positively, and this general factor is referred to as g. ...
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The average mammal or bird has a roughly ten times larger brain relative to body size than the average ectotherm vertebrate. It has been surprisingly challenging to determine how this translates into increased cognitive performance. In particular, it is unclear whether the brain size differences translate into qualitative differences in specific cognitive abilities. Here, we provide a first exploratory study to examine the possibility that the larger brains of endotherms support a different organisation of information processing, rather than specific differences in cognitive processes. In mammals, individual performance across domain‐general cognitive tasks is positively correlated, resulting in the psychometric factor g. The value of g is positively correlated with brain size. We tested wild‐caught female cleaner fish Labroides dimidiatus, known for its highly sophisticated social behaviour, in four ecologically nonrelevant cognitive tasks that have been used to varying degrees to assess g in mammals. Cleaner fish solved three of these four tasks, flexibility (reversal learning), self‐control (detour around an obstacle) and numerical competence (simultaneous two‐choice task), while also providing enough interindividual variation to test for g. They did not perform above chance levels in the fourth task, which tested for object permanence. For the three retained tasks, individual performance did not load positively on one principal component. Furthermore, all pairwise correlation coefficients were close to zero. These negative results contradict a frequent criticism of g studies, which proposes that g is a default result of how brains are designed. Rather, the results provide a first indication that endotherm and ectotherm vertebrates may process cognitive tasks in fundamentally different ways due to differences in brain organisation. Our relatively low number of experiments compared to mammalian studies enhances this hypothesis, as the probability of finding a g factor by chance would have been higher. It is known that endotherm vertebrates have on average a ten times larger brain relative to body size compared with ectotherm vertebrates. It remains largely unknown what advantages the larger brains convey. Our preliminary study may provide a partial answer: it appears that cleaner fish cognitive abilities are organised in a rather modular way (Figure), and that their brain may hence lack centralised units that cause correlated individual performance across cognitive domains, yielding the general intelligence factor ‘g’ in mammals. Figure: No evidence for g in a fish. Principal component analysis (PCA) of the three cognitive tasks. Dimension 1 (explaining 38.54% of the variance in performance) and dimension 2 (explaining 32.78% of the variance) are represented. The results for each task are represented as vectors.
... Eines der Strukturmodelle ist Gardners (2006) Modell der multiplen Intelligenzen, in dem mehrere Formen von Intelligenz unterschieden werden. Spearman (1904b), Jensen (1989) und Mackintosh (2011) ...
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Die Struktur musikalischer Fähigkeiten ist bislang nicht eindeutig identifiziert. Die vorliegende Studie untersucht, ob es analog zu Gardners Konzept der multiplen Intelligenzen mehrere unabhängige Musikalitäten gibt oder analog zu Spearmans Generalfaktor der Intelligenz hingegen nur einen allgemeinen Musikalitätsfaktor. Hierbei wird Musikalität im Rahmen der LongGold-Studie mittels Tests zur Beat- und Intonationswahrnehmung sowie zur Melodie- und Emotionsunterscheidung an einer Stichprobe aus Jugendlichen (N = 1786) zwischen acht und 18 Jahren (M = 11,78, SD = 1,68) in Deutschland und Großbritannien gemessen. Insgesamt zeigen die Testwerte mittlere bis hohe Korrelationen. Der Vergleich zweier latenter Variablenmodelle und eine konfirmatorische Faktorenanalysen geben Hinweise darauf, dass das Modell des allgemeinen g-Faktors der Intelligenz wahrscheinlich ebenfalls für musikalische Fähigkeit konzeptualisiert als einfaktorielles Modell gilt. Für die einzelnen Musikalitätstests werden Normwerte bereitgestellt, die nach Alter, Geschlecht und Ausmaß der musikalischen Ausbildung differenziert sind.
... The measure was developed for ages 5-11, and since then it has been subject to several validation studies among English-speaking or international participants, which have produced strong evidence for its construct (Facon et al. 2011;Goharpey et al. 2013;Van Herwegen et al. 2011) and discriminant validity, such as when demonstrating cognitive dysfunction in cerebral palsy (Pueyo et al. 2008). The matrices have been normed in over 35 countries and are now considered to be one of the most valid measures of g (Jensen 1998) or general intelligence (Abad et al. 2004;Mackintosh 1996), especially as a culture-free measure. Interestingly, a Google search reveals 6,820,000 pages for CPM and google scholar shows 23,400 empirical studies, verifying their wide implementation and use. ...
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The purpose of the present study was to evaluate the psychometric properties of Raven’s colored progressive matrices by estimating the presence of pseudo-guessing and pseudo-carelessness. Participants were 1127 children from ages 5 to 11. Guessing and carelessness were assessed using the lower and upper asymptotes of the 3PL and 4PL item response theory (IRT) models, respectively. Optimal model fit was judged using difference loglikelihood tests and information criteria. Results indicated that guessing, but not carelessness, were evident in the AB and B forms of the CPM, with successful guessing being more prevalent in the AB form. It is concluded that nonverbal IQ estimation in CPM should include variable estimation methods so that aptitude scores are estimated with the highest possible accuracy
... Unit-weighted estimation is then used to composite these effect-size vectors into a common factor along with the vectors of the subtest GCA loadings, White-Black-Hispanic performance differences (expressed as r-statistics with weighted averaging) for each subtest, PGS EDU -by-subtest associations, and subtest additivity (A), shared environmentality (C), and nonshared environmentality (E) components estimated using the twin (plus full siblings) subset (also rescaled as r-statistics). This configuration allows for a determination of whether or not gene-by-environment interactions might contribute to the differences posited by modern versions of Spearman's hypothesis, which hold that the magnitude of the differences in ability means between SIRE groups is positively moderated by GCA 5 (Jensen, 1980(Jensen, , 1998Spearman, 1927; see also the more contemporary work of The results of vector correlation analyses involving clustering among multiple correlated vectors have been offered as evidence for the so-called hereditarian hypothesis 6 on the basis that the magnitudes of the impacts of 'genetic' factors (such as inbreeding depression) on IQ battery subtests have been found to cluster along with the vectors of subtest GCA loadings and (specifically) White-Black mean performance differences, whereas the vectors of probably largely, possibly entirely, environmental effects, such as the Flynn effect (the secular increase in IQ test scores across decades), do not cluster with these effects (Rushton, 1999). In an item-level analysis of Raven's Progressive Matrices 'puzzles', Rushton et al. (2007) observed that in comparisons involving multiple SIRE groups, the group difference magnitudes in performance across items were correlated (positively) with their heritabilities, but not with their environmentalities (after controlling for item reliability and pass-rate variance). ...
Article
It has been hypothesized that even ‘perfect’ polygenic scores (PGSs) composed of only causal variants may not be fully portable between different social groups owing to gene-by-environment interactions modifying the expression of relevant variants. The impacts of such interactions involving two forms of social adversity (low socioeconomic status [SES] and discrimination) are examined in relation to the expressivity of a PGS for educational attainment composed of putatively causal variants in a large, representatively sampled and genotyped cohort of US children. A relatively small-magnitude Scarr–Rowe effect is present (SES × PGS EDU predicting General Cognitive Ability [GCA]; sR = .02, 95% CI [.00, .04]), as is a distinct discrimination × PGS EDU interaction predicting GCA ( sR = −.02, 95% CI [−.05, 00]). Both are independent of the confounding main effects of 10 ancestral principal components, PGS EDU , SES, discrimination and interactions among these factors. No sex differences were found. These interactions were examined in relation to phenotypic and genotypic data on height, a prospectively more socially neutral trait. They were absent in both cases. The discrimination × PGS EDU interaction is a co-moderator of the differences posited in modern versions of Spearman’s hypothesis (along with shared environmentality), lending support to certain environmental explanations of those differences. Behavior-genetic analysis of self-reported discrimination indicates that it is nonsignificantly heritable ( h ² = .027, 95% CI [−.05, .10]), meaning that it is not merely proxying some underlying source of heritable phenotypic variability. This suggests that experiences of discrimination might stem instead from the action of purely social forces.
... Second, a century of research on general intelligence and cognitive performance has overshadowed the role of non-cognitive EI factors that may effect academic achievement. This has led to a consensus among educators that cognitive factors, like high scores on intelligence tests, predict student performance in college (Jensen, 1998). Yet, many students still fail to live up to their true potential despite their IQ or previous academic performance. ...
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The present paper is an attempt to examine relationship between emotional intelligence and academic achievement motivation. It also studies the emotional intelligence of students with high, average and low academic achievement motivation. Sample for the study includes 105 students (48 boys and 57 girls) of class XII of Patna. The data were analyzed with the help of product moment coefficients of correlation. The findings of the study reveal positive relationship between emotional intelligence and academic achievement motivation. The study also reveals that students with high, average and low academic achievement motivation differ from one another on emotional intelligence.
... People have been conditioned that intelligent individuals are bound to succeed. Numerous studies have established that intelligence and achievement are highly correlated (Chandra, and Azimmudin, 2013;Jensen, 1998 as cited in Kaya, Juntune, & Stough, 2013). In various measures of success, IQ accounted for 33% of the variance (Neisser et al, 1996). ...
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It is widely accepted that intelligent individuals are more likely to succeed compared to academically challenged individuals. Knowledge is, without a doubt, a powerful tool. But interestingly, for long-term goals, it should be sealed with perseverance and passion, which is termed as grit, a non-cognitive trait. This study assessed the academic performance, grit and academic self-efficacy of 303 senior high school students in North District Carmen, Cebu using standardized scales. For data analysis, Pearson's correlation coefficient and multiple regression analysis were utilized as statistical tools. The results revealed that students' academic performance is rated as proficient with m = 86.86, SD = 3.31. Students' grit score has a m = 3.40, SD = 0.29, which indicates an above-average level of grit. In terms of academic self-efficacy, students have a mean of 4.00, SD = 0.46, indicating an above-average level of academic self-efficacy. Furthermore, a significant positive correlation among students' academic performance, grit, and academic self-efficacy was found with statistical significance at the level .01. It is concluded that an increase in grit and academic self-efficacy scores leads to an increase in academic performance. Finally, multiple regression analysis shows that students' grit and academic self-efficacy are statistically significant predictors of academic success, accounting for 12.3% of the variance in academic performance.
... RPM is a classic test of nonverbal reasoning, commonly referred to as matrix reasoning, and has been used as a core component in deriving global cognition, g [24]. RPM assesses abstract, visual problem-solving ability without the language or motor demands of other cognitive assessments [15]. ...
Article
Introduction Haemoglobin concentrations decrease with age. Abnormally low and high haemoglobin concentrations are associated with reduced cognition; however, the evidence for these associations in cohort data is limited. This study aims to assess the relationship between haemoglobin concentration and cognition in a well-characterised cohort of older adults. Methods Two hundred and fifty-two healthy participants were drawn from the Aberdeen Children of the 1950s cohort, aged between 59 to 65 years. Participants underwent cognitive tests of processing speed, memory, verbal and nonverbal reasoning, and language ability and these were used to construct a global cognitive score, g, using principal component analysis. Haemoglobin concentration in the blood was measured concurrently. Hierarchical multiple regression models were constructed assessing the relationship between haemoglobin concentration and each cognitive measure and these were corrected for age, sex, education, C-reactive protein, hypertension, and body mass index. Results Significant linear association between haemoglobin concentration and nonverbal reasoning demonstrated that low haemoglobin levels are associated with lower scores. A quadratic relationship was found for haemoglobin concentration and immediate memory scores in which low and high haemoglobin levels were associated with lower scores. Conclusions Haemoglobin concentration was found to have a significant linear association with nonverbal reasoning scores and a significant quadratic association with memory scores. The results from this study help to understand the association between haemoglobin and different aspects of cognition.
... ., Rindermann & Ackermann, 2021;te Nijenhuis et al ., 2019) . Jensen (1998) named a g-loading of 80% and added: "I have yet to see a factor analysis of any diverse collection of tests that includes Raven's Matrices in which the Raven's largest loading was found on any factor other than g" (p . 23) . ...
... Note that both X and X −i contain measurement error (as shown in Figure 1), which may produce biased estimation of the item-test relationship (Douglas, 1997;Guo & Sinharay, 2011). To minimize the impact of the measurement error on the biserial correlation estimation, we used the correction for attenuation method (Jensen, 1998;Spearman, 1904); that is, the second modification of x is ...
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It is desirable for an educational assessment to be constructed of items that can differentiate different performance levels of test takers, and thus it is important to estimate accurately the item discrimination parameters in either classical test theory or item response theory. It is particularly challenging to do so when the sample sizes are small. The current study reexamined the relationship between the biserial correlation coefficient and the discrimination parameter to investigate whether the biserial correlation coefficient estimator could be modified and whether biserial-based estimators could be used as alternate estimates of the item discrimination indices. Results show that the modified and alternative approaches work slightly better under certain circumstances (e.g., for small sample sizes or shorter tests), assuming normality of the latent ability distribution. Applications of these alternative estimators are presented in item scaling and weighted differential item functioning analyses. Recommendations and limitations are discussed for practical use of these proposed methods.
... 464-467) or variants of this method. Another solution is to carry out several replications, and to carry out a series of metaanalyses and correct for well-known measurement errors (Jensen, 1998). ...
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Intelligence tests are excellent predictors of school and job performance and racial/ethnic differences in mean IQ are common. Based on five lines of evidence, Warne (2021) builds a case for partly genetic causes of differences in general intelligence (g) across American Self/Parental-identified race or ethnicity. Based on a careful reading of Warne (2021) and the authors he cites, we generated 15 predictions flowing from a partial genetic hypothesis. These predictions concern (1) mean differences, (2) measurement invariance, (3) high within-group heritability, (4) admixture regression for g, (5) polygenic scores, (6) brain volume, and (7) Spearman’s hypothesis. We used the Adolescent Brain Cognitive Development Study sample (N = 10,245) to test these hypotheses using classical and state-of-the-art statistical techniques. Decomposition of variance using twins showed that the heritability of intelligence and of brain/intracranial volume estimates were, respectively, moderate and high for the White and the non-White subsamples. Within all SIRE groups, both genetic ancestry and education-related polygenic scores (eduPGS) predicted both brain volume and g. Moreover, brain volume was weakly but significantly related to g (r = .14 to .25). Path and causal mediation analysis showed that total brain volume explained approximately 15% of the association between European ancestry and g and also explained approximately 8% of that between eduPGS and g. Finally, based on the Method of Correlated Vectors (MCV), a positive manifold was found for genetic, brain volume, and ancestry/SIRE-related variables. We conclude that the results support the hypotheses tested and are in line with a partial genetic hypothesis.
... Just as people differ in virtually all complex tasks, they probably differ in proofreading performance. If so, one factor that might account for at least some of this variance is cognitive ability, as it does for most complex tasks (Jensen, 1998). Daneman and Stainton (1993) found that reading comprehension scores correlated with proofreading ability. ...
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The self-generation effect refers to the finding that people’s memory for information tends to be better when they generate it themselves. Counterintuitively, when proofreading, this effect may make it more difficult to detect mistakes in one’s own writing than in others’ writing. We investigated the self-generation effect and sources of individual differences in proofreading performance in two eye-tracking experiments. Experiment 1 failed to reveal a self-generation effect. Experiment 2 used a studying manipulation to induce overfamiliarity for self-generated text, revealing a weak but non-significant self-generation effect. Overall, word errors (i.e., wrong words) were detected less often than non-word errors (i.e., misspellings), and function word errors were detected less often than content word errors. Fluid intelligence predicted proofreading performance, whereas reading comprehension, working memory capacity, processing speed, and indicators of miserly cognitive processing did not. Students who made more text fixations and spent more time proofreading detected more errors.
... Readers should be mindful that attenuated coefficients are artificially weakened by the unreliability inherent to all psychometric measures. Therefore, the true effect sizes related to the five recognition patterns found here are likely to be much larger than they appear (for discussions, see e.g., Jensen, 1998;Lange et al., 2019). That said, we were not experimentally blind to the hypotheses when collecting and interpreting the data in this case. ...
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Haunted People Syndrome (HP-S) denotes individuals who recurrently report various “supernatural” encounters in everyday settings ostensibly due to heightened somatic-sensory sensitivities to dis-ease states (e.g., marked but sub-clinical levels of distress), which are contextualized by paranormal beliefs and reinforced by perceptual contagion effects. This view helps to explain why these anomalous experiences often appear to be idioms of stress or trauma. We tested the validity and practical utility of the HP-S concept in an empirical study of an active and reportedly intense ghostly episode that was a clinical referral. The case centered on the life story of the primary percipient, a retired female healthcare worker. Secondary percipients included her husband and adult daughter, all of whom reported an array of benign and threatening anomalies (psychological and physical in nature) across five successive residences. Guided by prior research, we administered the family online measures of transliminality, sensory-processing sensitivity, paranormal belief, locus of control, desirability for control, and a standardized checklist of haunt-type phenomena. The primary percipient also completed a measure of adverse childhood events and supplied an event diary of her anomalous experiences. We found reasonably consistent support for HP-S from a set of quantitative observations that compared five proposed syndrome features against the family members’ psychometric profiles and the structure and contents of their anomalous experiences. Specifically, the reported anomalies both correlated with the family’s scores on transliminality and paranormal belief, as well as elicited attributions and reaction patterns aligned with threat (agency) detection. There was also some evidence of perceptual congruency among the family members’ anomalous experiences. Putative psi cannot be ruled out, but we conclude that the family’s ordeal fundamentally involved the symptoms and manifestations of thin (or “permeable”) mental boundary functioning in the face of unfavorable circumstances or overstimulating environments and subsequently acerbated by poor emotion regulation, histrionic and catastrophizing reactions, and active confirmation biases.
... 7 While overlapping with the European strands' notion of 'bioculture', the American strands focus more on the underlying genetics (and evolutionary psychology) of group racial differences and of White identity. Under this view, the millennia of separation between races, adapting to substantially different environments, created evolutionary differences in discrete populations, which include differences in intelligence, time preference and impulse control (resulting in emotionality and hypersexuality), rule-following, and child-rearing, susceptibility to certain types of illnesses, compatibility of blood plasma, and so forth (see Jensen 1998;Rushton 2000). Statements that racial differences are only 'skin deep' or social constructions are viewed as highly unscientific and a form of 'cognitive creationism'. ...
Chapter
The ‘Alt-Right’ exhibits intersectionality in a new key. Rather than mere reaction, the Alt-Right – gaining narrative cohesiveness through whiteness – is intersectionality, merely with a different frame of reference for marginalisation, oppression, and populations of concern. In the case of the Alt-Right, whiteness (variously defined) serves as the connecting narrative for other elements (masculinity, localism, etc.) in a manner similar to marginalised racial populations serving as the narrative connection within other forms of mainstream intersectionality (feminism, post-colonialism, queer theory, and others). Moreover, Alt-Right and progressive forms of intersectionality share numerous opponents, particularly capitalism, neoliberalism, and homogenising globalisation (usually referred to as ‘globalism’ by the Alt-Right). Whiteness acts as the mode of resistance for Alt-Right intersectionality: specifically, as a resistance to whiteness as a null category (that ‘whiteness’ denotes no culture or discernible characteristics) or as a negative culture (that ‘whiteness’ is solely defined by oppression and marginalisation of others, by colonialism, and so forth). The Alt-Right construction varies from earlier forms of white identity politics and white nationalism in that its shape and fundamental structure reflects that of intersectionality: the Alt-Right likely would not exist without the previous and partial ‘mainstreaming’ of intersectional language in Western societies.
... Over a century of research has established that measures of cognitive ability correlate positively with one another, a phenomenon which intelligence researchers refer to as the positive manifold (Spearman, 1904(Spearman, , 1927. Simply put, people who perform poorly on one cognitive ability test tend to perform below average on other tests, too (Carroll, 1993;Jensen, 1998). This maxim holds for tests measuring different broad cognitive abilities, such as knowledge (i.e., crystallized intelligence), reasoning (i.e., fluid intelligence), and memory (i.e., working memory capacity), as well as for tests tapping different content areas, such as math, verbal, or visuospatial skills. ...
Article
Process overlap theory provides a contemporary explanation for the positive correlations observed among cognitive ability measures, a phenomenon which intelligence researchers refer to as the positive manifold. According to process overlap theory, cognitive tasks tap domain-general executive processes as well as domain-specific processes, and correlations between measures reflect the degree of overlap in the cognitive processes that are engaged when performing the tasks. In this article, we discuss points of agreement and disagreement between the executive attention framework and process overlap theory, with a focus on attention control: the domain-general ability to maintain focus on task-relevant information and disengage from irrelevant and no-longer relevant information. After describing the steps our lab has taken to improve the measurement of attention control, we review evidence suggesting that attention control can explain many of the positive correlations between broad cognitive abilities, such as fluid intelligence, working memory capacity, and sensory discrimination ability. Furthermore, when these latent variables are modeled under a higher-order g factor, attention control has the highest loading on g, indicating a strong relationship between attention control and domain-general cognitive ability. In closing, we reflect on the challenge of directly measuring cognitive processes and provide suggestions for future research.
... (Dreary, Stand, Smith and Fernandez, 2007). High performance in such tests is also predictive of broad success like social well-being and mental health [3]. ...
... IQ scores obtained from full-scale intelligence tests are also extremely repeatable, with test-retest reliabilities consistently over .90 (see Jensen, 1998;Roid, 2003;Wechsler, 2008). In non-human animals, aggregate ratings based on multiple behaviors can also reach high levels of repeatability (e.g., about .80 in Uher et al., 2008). ...
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Harrison et al. (2021) set out to test the greater male variability hypothesis with respect to personality in non-human animals. Based on the non-significant results of their meta-analysis, they concluded that there is no evidence to support the hypothesis, and that biological explanations for greater male variability in human psychological traits should be called into question. Here, we show that these conclusions are unwarranted. Specifically: (a) in mammals, birds, and reptiles/amphibians, the magnitude of the sex differences in variability found in the meta-analysis is entirely in line with previous findings from both humans and non-human animals; (b) the generalized lack of statistical significance does not imply that effect sizes were too small to be considered meaningful, as the study was severely underpowered to detect effect sizes in the plausible range; (c) the results of the meta-analysis can be expected to underestimate the true magnitude of sex differences in the variability of personality, because the behavioral measures employed in most of the original studies contain large amounts of measurement error; and (d) variability effect sizes based on personality scores, latencies, and proportions suffer from lac of statistical validity, adding even more noise to the meta-analysis. In total, Harrison et al.'s study does nothing to disprove the greater male variability hypothesis in mammals, let alone in humans. To the extent that they are valid, the data remain compatible with a wide range of plausible scenarios.
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The abstract for this document is available on CSA Illumina.To view the Abstract, click the Abstract button above the document title.