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The short answer: No, sex differences in professions is not a good basis for judging the intelligence of males and females. I would like to address some of the assumptions and misconceptions in the question. First, I would like to deconstruct the question, and then answer it. Deconstructing the question One of the earlier titles of the question was "Are ...


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As a general note, precision in measurement of intelligence declines as you move to more extreme levels. There is greater uncertainty in measurement in the 145 range than there is at the 100 range. Norm samples get smaller, and most measures of intelligence are designed for the normal range. Categories: You might find the article on IQ classification useful....


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Literal IQ: In a literal sense, IQ is a standardised score derived from intelligence tests. Typically IQ is scaled to have a a mean of 100 and a standard deviation of 15. In that sense, it is a normative score. For children, the norm is defined relative to other children of a similar age, for adults, it is defined relative to an adult population. IQ as g: ...


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You are asking two very excellent questions. Is the decline in fluid intelligence commonly accepted as true? These days it seems generally accepted, that the trend is true. However, this hasn´t been the case a few yeas ago, e.g. see the introduction in Elsayed, Ismail, & Young (1980) for a little impression. The reason behind this is the limited ...


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IQ scores in general: An IQ score is a normative score. The norm group is typically defined as the general population, and where the respondent is a child, the norm group is defined in terms of the general population of children of that same age. IQ scores typically have a mean of 100 and a standard deviation of 15. In order to get an estimate of ...


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There is little neurological evidence that finds a difference between men and women. However there are psychological studies that do find a small difference in mental strengths. This interesting TED talk debunking psychological myths by a lecturer from the University of Liverpool discusses the psychological differences between men and women. Males and ...


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Recent studies on this topic deal with more detailed questions, that are analysed using structural equation models (Deary et al., 2006). A main goal has been the identification of specific genes. No single genes have been found until today and Sternberg (2012) also points out that the concept of heritability itself is indirect and maybe inappropriate if ...


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Is there any evidence of malleability of fluid intelligence? In the downward direction, definitely yes. There are many ways you can directly pull fluid intelligence downwards. Things like being exposed to much lead, suffering from iodine deficiency (especially a developing fetus during pregnancy, see e.g. (Qian et al, 2005)), or by not getting decent ...


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Because it has been a few years since Jeromy's original answer, and because I just read a very apt article, I will venture an update on the state of the field with respect to the BPI's validity. Overall, despite more research into brain training and Lumosity, there is little to no peer-reviewed evidence supporting the Lumosity BPI's validity, nor evidence ...


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Firmin et al. (2008) tested the validity of a handful of online IQ tests by having college students complete IQ tests at three different websites and also complete a validated lab measure, the Reynolds Intellectual Assessment Scales (RIAS). They found that there were moderate correlations ($r$ values were around 0.4 to 0.5) between some of the online tests ...


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Actually, standard IQ tests, such as Raven's matrices, tend to assess intelligence better if they are not timed. In this paper by Philip Vernon (1988) it was found that the g-factor extracted slightly more variance for the same test if the test was not timed than if it had a time limit. This means if you ask yourself: "What is this test measuring?", you can ...


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Multiple causes of not reading instructions As @crash notes, there are likely many explanations for not reading instructions. It may be motivated by not caring about task performance. And such dispositions may be specific to the particular task or setting, or they might be partially related to some general disposition of the individual in terms of ...


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The question you have asked is not a new one. In fact, from the times of classical antiquity, Plato considered artistic creativity as a result of god-given madness. When it comes to popular figures in the arts and sciences, however, it is important to note that the illness is not restricted to them by any means. Lord Byron and Beethoven are said to be manic-...


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I think what happens is that researchers often don't report on - or at least don't highlight - uninteresting results, partly because of the difficulty getting uninteresting results published. So given that gender differences in IQ in general are eliminated for validity, a lack of gender differences in IQ amongst a seemingly arbitrary sub-population such as ...


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The Torrance Test of Creative Thinking is a good place to start. It scores for fluency (number of responses) as well as originality (statistical rarity of responses) and elaboration (level of detail) on a variety of different tasks. The validity of the TTCT has been examined with several long-term studies, so there is a fair amount of data on its ...


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Yes, practice even as simple retest improves scores in matrices-like tests: Raven’s APM scores increase significantly on repeated testing without any targeted training (e.g., Bors & Vigneau, 2003; Bors & Forrin, 1995; Denney & Heidrich, 1990). Bors DA, Vigneau F. The effect of practice on Raven’s advanced progressive matrices. Learning ...


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The correlation between physical attractiveness and IQ is somewhere between insignificant and mildly positive, with a slightly higher correlation for men. The correlation between physical attractiveness and perceived intelligence is more significant. There are typically two approaches to explain the (albeit mild) correlation: Nature: From an evolutionary ...


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To add to the existing answers (of which @what's gets special mention), an issue I don't think has really been addressed is the statistical reason for it being so difficult to measure extremely high IQs. By design, IQ is scaled so that it's normally distributed, with a mean of 100, and a standard deviation (SD) of 15. A well known feature of the normal ...


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Kazimierz Dabrowski had a great theory (the Theory of Positive Disintegration) about the relationship between psychoneuroses, the most common symptoms of mental illness, and the developmental trajectories of gifted people. In brief, gifted people are more likely to live out-of-sync with their social environments (too smart, too intense, too righteous, too ...


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I hadn't heard of the Bhatia measure before. A little research (see page 42 of Sharma and Sharma) explains that it is a performance based measure of ability for children in India. In general, you should obtain the test manual to learn about the recommended scoring procedure. A quick Google suggests it might be available from here: http://www.npcindia.com/ ...


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So you're basically asking what are the causes of interpersonal differences in intelligence as typically measured by standardised psychometric tests. This question forms the basis for a large proportion of the literature on intelligence. For example see a journal like Intelligence. For a review you could read Intelligence: Knowns and Unknowns A few quick ...


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A systematic meta-analysis of the relationship between IQ and obesity (Yu, Han, Cao and Guo, 2010) suggested that lower IQ in childhood was associated with later adult obesity via educational level. No evidence of a relationship between IQ and obesity was found for adults. Our study and review of the literature overall suggests that there are inverse FIQ/...


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Consider, a normal IQ score falls between the range 85-115 which is approximately 70% of the population (and only 15% of people have an IQ of 115 or above), while an extended average IQ range tends to encompass those between 80-119 which is "x"% of the population. In order to qualify for the International High IQ Society, one must have an IQ of 125 or above, ...


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Short answer IQ scores are distributed normally, because they follow the central limit theorem. Background When we measure IQ scores in sufficiently large populations, they will be normally distributed. This holds for healthy controls, as well as groups of people with ADHD or reading disabilities (Kaplan et al., 2000), and also in people with mild to ...


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PCA or EFA: A standard approach to calculating a g factor would be to use principal components analysis (PCA) or exploratory factor analysis (EFA). Basically, you administer a broad battery of cognitive ability measures. Then you use these tests as variables in a PCA or EFA. This will partition the variance in the tests into a set of uncorrelated factors. ...


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There are a few ways that you could answer this question. First, IQ is defined with a mean of 100 and a standard deviation of 15. But this is a normative score and relative to a given target population typically defined by time, geography, and various inclusion criteria. In particular, IQ scores have increased over time (i.e., Flynn effect). So by this ...


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