For this study, European WAIS III performance subtest norms were compared to the original US norms. When European WAIS III raw scores were scored using US norms, the resulting perceptual organization index (POI) means were significantly higher than the processing speed index (PSI) means. The POI/PSI difference is roughly 5-10 points for the German…

Two structural laws for intelligence tests are discussed: one law concerns the sign of correlation coefficients and gives conditions under which all correlations between test items will be positive; and one law concerns the relative sizes of the correlation coefficients between intelligence items. A cylindrical structure extends these laws. (SLD)

A number of studies in the United States have found that Jews obtain higher average IQs than white gentiles. This paper examines whether this is also the case in Britain. Three early studies are summarized that found that Jews in Britain have mean IQs in the range of 110-113. New data are presented for two nationally representative samples of 7-16…

Intellectual abilities were measured for 217 German and 205 American college students using tests (in the subjects' native languages) in which equivalence was established by an item-response theory-based differential-item-functioning (DIF) analysis. Comparisons between groups were not the same before and after removal of DIF items. (SLD)