We examined whether the General Factor of Personality (GFP) is related to the "g" factor of cognitive ability using data from the Vietnam Experience Study which randomly sampled 4462 Vietnam War veterans from a total sample of about five million Vietnam era army veterans. Exclusionary criteria included passing a fitness test, achieving a…

A link between pre-morbid intelligence and all cause mortality is becoming well established, but the aetiology of the association is not understood. Less is known about links with cause specific mortality and with morbidity. The aim of this study is to examine the association between intelligence measured in adolescence and a broad range of health…

This study investigated the possibility that apparent sex differences in IQ are at least partly created by the degree of sample restriction from the baseline population. We used a nationally representative sample, the 1970 British Cohort Study. Sample sizes varied from 6518 to 11,389 between data-collection sweeps. Principal components analysis of…

There is scientific and popular dispute about whether there are sex differences in cognitive abilities and whether they are relevant to the proportions of men and women who attain high-level achievements, such as Nobel Prizes. A recent meta-analysis (Lynn, R., and Irwing, P. (2004). Sex differences on the progressive matrices: a meta-analysis.…

Individual differences in confidence judgments made by subjects on the accuracy of their answers to psychological test items were studied with 271 Australian college students. Findings suggest that confidence ratings, like the accuracy scores from the tests of human abilities, are stable and reliable measures of between-subjects variability. (SLD)

Two studies (N=4,261 persons) illustrate an inverse relationship between ability level and correlations among IQ measures. Low IQ subjects showed higher correlations than did high IQ subjects. Intercorrelations of IQ subtests, intercorrelations of cognitive ability measures, and correlations of IQ with measures of cognitive ability displayed the…