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Richard Lynn

Publications and source records attributed to Richard Lynn.

12 recordsLinked to original sources
PubMed2006

Intelligence differences between European and oriental Jews in Israel.

A number of studies have found that Ashkenazi Jews in the United States have a high average IQ. It has been proposed by Cochran, Hardy and Harpending (2006) that this can be explained by the occupational constraints imposed on the Ashkenazi for many centuries in Europe, when they were largely confined to money-lending. They propose that this selected for the high verbal and mathematical intelligence that has several times been found in American Ashkenazim. The current study investigates how far this theory holds for European and Oriental Jews in Israel. A review of studies shows that Oriental Jews in Israel have an average IQ 14 points lower than that of European (largely Ashkenazi) Jews. It is proposed that this difference can be explained in terms of the Cochran, Hardy and Harpending theory because Oriental Jews were permitted to engage in a much wider range of occupations and hence did not come under the selection pressure to develop the high verbal and mathematical intelligence that was present for Ashkenazim.

Asia↗
PubMed2006

Intelligence: is there a sex difference in IQ scores?

Arising from: S. Blinkhorn Nature 438, 31-32 (2005); Blinkhorn replies. Steve Blinkhorncriticizes our study of samples of university students, in which we found that the average IQ of men is 4.6 points higher than that of women, as measured by the Progressive (or Raven's) Matrices. He maintains that there is a negligible sex difference in adult intelligence. We believe that the principal error of Blinkhorn's criticism is that he does not consider our result in the context of several other studies showing that adult males have an IQ advantage of around 4-6 IQ points.

Adolescent↗
PubMed2006

Using multiple sources to improve and measure case ascertainment in surveillance studies: 20 years of the British Paediatric Surveillance Unit.

BACKGROUND: The British Paediatric Surveillance Unit (BPSU) was established in 1986 to facilitate national surveillance of uncommon paediatric disorders. This study investigated the effectiveness of using multiple source reporting and capture-recapture analysis to maximize case ascertainment in studies undertaken through the BPSU. METHODS: Structured review of all surveillance studies completed through the BPSU. Quantitative and qualitative analysis of the effectiveness of multiple reporting sources and capture-recapture methods was made. RESULTS: Of 71 studies undertaken through the BPSU, 59 were included in this review and 38 used additional data sources. Established national sources were most readily adapted for use as secondary data sources, including routine health data, communicable disease and specialty-specific surveillance units, whilst the involvement of parent groups and the media was less successful. Six studies employed capture-recapture techniques to estimate the completeness of case ascertainment. CONCLUSIONS: Active surveillance through the BPSU remains a timely and reliable primary source of cases, but employing additional reporting sources is effective in enhancing case ascertainment. When the assumptions for its valid use are met, capture-recapture analysis allows the estimation of completeness of ascertainment. It is essential to define the purpose of an additional source at the outset of a study and to ensure that subsequent analysis is appropriate.

Data Collection↗
PubMed2005

Ethnic and racial differences on the Standard Progressive Matrices in Mexico.

Raven's Standard Progressive Matrices test was administered to a representative sample of 920 white, Mestizo and Native Mexican Indian children aged 7-10 years in Mexico. The mean IQs in relation to a British mean of 100 obtained from the 1979 British standardization sample and adjusted for the estimated subsequent increase were: 98.0 for whites, 94.3 for Mestizos and 83.3 for Native Mexican Indians.

Achievement↗
PubMed2005

Sex differences in means and variability on the progressive matrices in university students: a meta-analysis.

A meta-analysis is presented of 22 studies of sex differences in university students of means and variances on the Progressive Matrices. The results disconfirm the frequent assertion that there is no sex difference in the mean but that males have greater variability. To the contrary, the results showed that males obtained a higher mean than females by between .22d and .33d, the equivalent of 3.3 and 5.0 IQ conventional points, respectively. In the 8 studies of the SPM for which standard deviations were available, females showed significantly greater variability (F(882,656) = 1.20, p < .02), whilst in the 10 studies of the APM there was no significant difference in variability (F(3344,5660) = 1.00, p > .05).

Adolescent↗
PubMed2004

The growth of IQ among Estonian schoolchildren from ages 7 to 19.

The Standard Progressive Matrices test was standardized in Estonia on a representative sample of 4874 schoolchildren aged from 7 to 19 years. When the IQ of Estonian children was expressed in relation to British and Icelandic norms, both demonstrated a similar sigmoid relationship. The youngest Estonian group scored higher than the British and Icelandic norms: after first grade, the score fell below 100 and remained lower until age 12, and after that age it increased above the mean level of these two comparison countries. The difference between the junior school children and the secondary school children may be due to schooling, sampling error or different trajectories of intellectual maturation in different populations. Systematic differences in the growth pattern suggest that the development of intellectual capacities proceeds at different rates and the maturation process can take longer in some populations than in others.

Adolescent↗
PubMed2003

Sex differences on the progressive matrices: some data from Hong Kong.

There has been a debate between N. J. Mackintosh and the first author of this paper on whether the sex difference on the Progressive Matrices is zero or, at most, 1-2 IQ points in favour of either sex, as maintained by Mackintosh, or whether from the age of 15 years onwards males obtain higher average scores than females by more than 2 IQ points, as maintained by Lynn. New data relevant to this controversy are presented from Hong Kong consisting of sex differences on the standardization sample of the Advanced Progressive Matrices on 15- to 18-year-olds. The results are that males obtained a higher mean score than females of 1.6 raw score points, equivalent to an advantage of 3.2 or 4.1 IQ points, according to two alternative methods of calculation. The results provide further confirmation that in later adolescence and among adults, males obtain significantly higher mean IQs on the Progressive Matrices than females.

Adolescent↗
PubMed2003

A new estimate of the IQ in Estonia.

The Standard Progressive Matrices was standardized in Estonia in 2001 on a sample of 1,835 7- to 11-yr.-olds. The mean IQ of the Estonian sample was estimated at 98 in relation to a British IQ of 100 and 99 based on the combined results for two studies.

Adolescent↗
PubMed2002

Sex differences in general knowledge, semantic memory and reasoning ability.

This paper has the three objectives of attempting to replicate a previous study in which it was found that males have substantially greater general knowledge in most fields or domains than females, and of determining how far sex differences in general knowledge are a function of differences in either Gf (fluid intelligence), or experience. The results confirmed the previous study to the effect that males have higher means in a general knowledge factor of approximately.50 d (half a standard deviation). It was found further that there was no significant sex difference in Gf measured by Baddeley's Grammatical Reasoning Test, and only a low correlation between general knowledge and Gf. Analysis of covariance showed that differential experience as indicated by 'A'-level points and socio-economic status had only a marginal impact on the observed sex difference. The results are interpreted as showing that sex differences in general knowledge cannot be explained as a function of differences in either Gf or experience. It is proposed further that general knowledge should be regarded as a new second-order factor and designated as semantic memory.

Adolescent↗
PubMed2002

A study of IQ in Lithuania.

Data for the Colored Progressive Matrices were collected for a sample of 259 8- to 12-yr.-old children in Lithuania in 1999. In relation to the British 1979 standardization sample the mean IQ of the Lithuanian children was 92.2. Adjusted for the estimated secular increase of intelligence in Britain, the Lithuanian mean IQ is estimated at 90.

Child↗
PubMed2002

A study of intelligence in Estonia.

The Standard Progressive Matrices was standardised in Estonia in 2001 on a sample of 2,689 12- to 18-yr.-olds. The mean IQ of the Estonian sample was approximately 5 points higher than British IQ norms of 1979. Adjustment for the estimated secular increase of intelligence in Britain reduces the mean IQ of the Estonian sample to 100.2, in relation to a British mean of 100. A particular interest of the result from Estonia is that the intelligence of a European population is apparently not impaired by decades of low living standards.

Adolescent↗