Norms for the Progressive Matrices for Libya and Tunisia
Lynn, Richard, Abdalla, Saleh El-Ghmary, Al-Shahomee, Alsedig Abdalgadr, Mankind Quarterly
Results are reported for intelligence in Tunisia based on a standardization sample of adults on the Standard Progressive Matrices and in Libya for a standardization sample of 6- to 11-year-olds on the Colored Progressive Matrices. In relation to a British IQ of 100, the mean IQ of the Tunisian sample is 84, and the mean IQ of the Libyan sample is 86.5. In the Libyan sample younger children performed better than older children. There was no difference between girls and boys in either means or variability.
Key Words: Intelligence; Progressive Matrices; Tunisia; Libya; Sex differences; Variability.
Not much is known about the intelligence of Nordi Africans. In a compilation of the intelligence of die populations of 113 nations, Lynn & Vanhanen (2002, 2006) were only able to give an IQ for Egypt (81) among the Nordi African nations. They assigned in addition an IQ of 85 to Morocco, but tiiis was based on immigrants in the Netiierlands who are not necessarily representative of the population. In order to fill diis gap in existing knowledge, we present here some data for population intelligence in Tunisia and Libya.
The data for intelligence in Tunisia come from a standardization of Raven's Standard Progressive Matrices (RPM, Raven et al., 2000) on adults carried out in 2001. The results are summarized by Abdel-Khalek & Raven (2006). The sample size was 509 and a score of 47 is given for die 50th percentile of 20year-olds, togedier widi a score of 54 for British 20-year-olds obtained in die 1992 standardization. The raw score difference of 7 is approximately equivalent to 14 IQ points, giving the Tunisian sample an IQ of 86. If a Flynn effect adjustment is made for an increase in the British IQ of 2 IQ points per decade, the British IQ will have increased by 2 IQ points from 1992 to 2001, and hence the difference between Britain and Tunisia will become 16 IQ points, reducing the Tunisian mean to 84, in relation to a British IQ of 100.
A further calculation of the IQ in Tunisia has recently been made by Rindermann (2007) . He adopts scores obtained in the 2003 PISA study of mathematics in 15-year-old school students as a measure of intelligence. In this study the mean score in 29 OECD economically developed countries was 489 (sd=104), and the mean score in Tunisia was 359 (sd=82). The difference between the economically developed countries and the Tunisians is 1.40 sd units, equivalent to an IQ difference of 21 IQ points. This calculation confirms earlier studies reviewed in Lynn & Vanhanen (2002, 2006) showing that the use of mathematics tests as proxies for intelligence tends to magnify the differences obtained from IQ tests. Nevertheless, the results from the Standard Progressive Matrices and from the mathematics test are broadly consistent, giving IQs of 84 and 79, respectively.
The CPM test in Libya
The Colored Progressive Matrices test (CPM, Raven et al., 1995) was standardized in Libya during the months of January and February 2006. A representative sample of 100 children from each of the six age groups 6.0 through 11.6 years old were tested. The sampling procedure comprised a multi-stage random sampling method (cluster sampling). The CPM was administered to pupils in first to sixth grades who where randomly selected from 7 elementary schools in the large city of El-Beida, 4 elementary schools in the small city of Shahat, and from 9 villages, selecting one school in each village. Children in Libya begin school at the age of 6.0 years and boys and girls are educated together. This ensures that the boys and girls are matched for educational experience and family background.
The results are summarized in Table 1. This gives the mean scores obtained by boys and girls of each age (age 6 = 6.5 years, age 7 = 7.5 years, etc), the standard deviations, the variance ratios (variance of the boys divided by variance of the girls) , and the percentile equivalents of the means of the boys and girls combined on the British norms for the Standard Progressive Matrices collected in 1979 given in Raven (1981). …