Race differences in intelligence: A global perspective
Af professor emeritus Richard Lynn
Abstract
Presents a review of the world literature on racial differences
in intelligence. Studies using intelligence tests; Studies of
reaction times; Contributions to civilization.
***
The world literature on racial differences in intelligence is
reviewed from three points of view. Firstly, studies using
intelligence tests indicate that Caucasoids in North America,
Europe and Australasia generally obtain mean IQs of around 100.
Mongoloids typically obtain slightly higher means in the range of
100-106. African Negroids obtain mean IQs of around 70, while
Negroid-Caucasoids in the United States and Britain obtain means of
about 85. Amerindians and the South East Asian races typically
obtain means in the range of 85-95.
A second source of evidence comes from studies of reaction times
which provide measures of the neurological efficiency of the brain.
These studies show that Mongoloids have the fastest reaction times
followed by Caucasoids and then by Negroids. Thirdly, the races can
be assessed for their contributions to civilization. Here the
Caucasoids and the Mongoloids have made the most significant
advances both in the foundation of the early civilizations and in
more recent developments.
The existence of racial differences in intelligence has been
known since the time of the First World war when tests given to
large numbers of military conscripts in the United States revealed
that blacks had an average intelligence level about 15 IQ points
below that of whites. In the following decades there has been
debate over the question of whether these differences have a
genetic basis. This debate has largely taken place in the context
of the differences in intelligence found in different racial
populations in the United States. Genetic theorists have pointed to
the high heritability of intelligence and the difficulties of
formulating credible environmentalist explanations to explain the
difference (Jensen 1972, 1973, 1980; Eysenck, 1971).
Environmentalists have pointed to a variety of factors which they
consider capable of explaining the low Negroid IQ, of which the
most important are bias in the tests, the adverse social and
economic living conditions experienced by blacks, discrimination
and prejudice from white majorities and the historical legacy of
slavery which has demoralized blacks and destroyed their family
structure (Flynn, 1980; Jaynes and Williams, 1989; Mackintosh and
Mascie-Taylor, 1985). Neither side has yet succeeded in convincing
the other and the issue remains unresolved, although a recent poll
has shown that the majority of experts now believe there is some
genetic basis to the low black IQ (Snyderman and Rothman,
1988).
The purpose of the present paper is to consider the problem of
racial differences in intelligence in a global perspective. Part
one of the paper contains a review of the many studies which have
been made of the intelligence of different races throughout the
world. The principal question here is whether the world wide
evidence supports the genetic or the environmental position.
In general terms the genetic theory requires that there should
be a reasonably high degree of consistency of the intelligence
levels shown by populations of different races in a variety of
geographical locations. Thus, Negroids should universally have
lower intelligence levels than Caucasoids and this difference
should be found in Africa and the West Indies as well as in the
United States and Britain. The reason for this is that the genes or
alleles (alternative forms of genes) for low intelligence, if these
exist, should be present in all Negroid populations and not merely
in those whose ancestors were transported as slaves to the New
World. Furthermore, Negroids in the United States and Britain are
nearly all Negroid-Caucasoid hybrids (Reed, 1969). Their Caucasoid
genes should, on the genetic hypothesis, raise their intelligence
level as compared with the pure Negroids of Africa. Hence the
genetic theory demands that African Negroids should have lower
intelligence levels than the Negroid-Caucasoid hybrids of the
United States and Britain. Whether or not this is the case can be
regarded as a test of the genetic theory and any studies showing
that pure African Negroids have higher IQs than American or British
Negroid hybrids would falsify the genetic hypothesis.
A similar degree of consistency of intelligence levels should be
found for all races if the intelligence is largely genetically
determined. The intelligence of Caucasoids should be approximately
the same, whether they live in the United States, Britain, Europe,
Australia or New Zealand. The same consistency should be present in
the third major race of mankind, the Orientals or Mongoloids, who
are present not only in their native habitat of north east Asia but
also in the United States and Europe. Hence a world wide
examination of the consistency of racial differences in
intelligence would provide a perspective on the genetic and
environmental theories which is lacking in the studies carried out
in the local contexts of the United States and, more recently, in
Britain.
Part two of the paper deals with the question of whether the
racial differences in intelligence as measured by intelligence
tests are also present in reaction times, i.e. the speed of
response to simple stimuli. The interest of this question is that
recent work has shown that reaction times are a measure of
intelligence and appear to represent differences in the
neurological efficiency of brain processes (Jensen, 1982; Eysenck,
1982). A positive finding of racial differences in reaction times
would rule out many of the explanations for the intelligence
differences advanced by environmentalists such as bias in the
tests, the legacy of slavery and so forth, and would point to a
genetically determined neurological basis for the differences.
Whether or not there are racial differences in reaction times which
run parallel with those in intelligence therefore provides a
further test of the genetic and environmental theories.
Part three of the paper considers the racial differences in the
foundation and advancement of civilization. The establishment of
civilization required numerous discoveries such as the invention of
writing and arithmetic and these must have been due to the work of
highly intelligent individuals. This part of the paper considers
whether the racial differences in the establishment of
civilizations are the same as those found in the performance of
intelligence tests.
Intelligence Test Performance
Intelligence tests were developed in the first two decades of
the century and in the following seventy years numerous studies
have been published of the intelligence of different peoples in
many parts of the world. The principal studies have been collated
and classified by the race and are summarized in Tables 1 through
6.
Intelligence was initially conceptualized as a single entity
quantified by the intelligence quotient and many studies have
reported racial differences in terms of a single IQ. theoretical
basis for representing intelligence in terms of a single IQ is
Spearman's (1927) work identifying a general factor present in all
cognitive tests and his conceptualization of this as general
intelligence, now known as Spearman's g, and identified as a
generalized problem solving ability which enters into the
performance of all cognitive tasks.
This theory of intelligence was challenged in the nineteen
thirties by Thurstone (1938) who proposed an alternative model
which dispensed with the concept of Spearman's g and postulated six
primary mental abilities designated reasoning, spatial, numerical,
verbal, perceptual speed and fluency abilities. In the late
nineteen-forties an integration of the Spearman and Thurstone
models was proposed by Burt (1949). This consisted of a
hierarchical model of intelligence in which Spearman's general
factor was split into two correlated group factors now generally
known as the verbal and visuospatial abilities. These can in turn
be broken down further into narrower primary abilities, of which
some twenty to thirty have been identified (Cattell, 1971). Burt's
model is widely accepted in contemporary psychology and is adopted
in this paper. Where possible means for different populations are
given for general intelligence (Spearman's g) and for the verbal
and visuospatial abilities.
Intelligence tests are normally calibrated with the mean IQ set
at 100 and the standard deviation at 15. This metric has been
adopted and the mean IQ of American Caucasoids set at 100 to serve
as the standard in terms of which IQs of all other populations are
expressed. Further details of the methods used of a single IQ. The
for the calculations of mean IQs for different populations are
given in the appendix.
Caucasoids
Mean IQs for Caucasoid peoples in the United States, Britain,
Continental Europe, Australia and New Zealand are set out in Table
1. In this and in subsequent tables summary results are given for
the geographical location of the sample, the age of the subjects,
tile numbers, the tests used and mean IQs for general, verbal and
visuospatial intelligence. General intelligence is conceptualized
as Spearman's g, the general factor present in all cognitive tasks,
and most effectively measured by tests of reasoning ability such as
Raven's Progressive Matrices and Cattell's Culture Fair Test. It
can also be measured by omnibus tests such as the Wechslers and the
Stanford Binet. Results from all these tests are entered in the
tables under general intelligence. Verbal IQs in the tables are
derived from the verbal scales of the Wechslers and from verbal
comprehension scales in such tests as the Differential Aptitude and
the McCarthy. Visuospatial IQs are derived from the performance
scales of the Wechslers and from visuospatial scales in the
Differential Aptitude, the McCarthy and similar tests, and from
figure copying tests such as the Draw-a-Man.
Inspection of the results set out in the table will show firstly
that Caucasoids in the United States and Britain obtain virtually
identical mean IQs. This was first demonstrated in the 1932
Scottish survey of 11 years olds who obtained a mean IQ of 99 on
the American Stanford Binet. The subsequent studies shown in the
table under Scotland and Britain confirm this result. The earlier
standardization of tests in the United States were generally based
on normative samples of Caucasoids only, such as the early Stanford
Binet and Wechsler tests, but the later standardizations such as
the WISC-R included Negroids. For this reason an adjustment has to
be made to American means for later tests, because when tile mean
of the American total population is set at 100, the mean of
American Caucasoids is 102.25, as derived from the standardization
sample of tile WISC-R (Jensen and Reynolds, 1982).
Further inspection of the results set out in Table 1 shows that
the mean IQs from all these Caucasoid populations lies in the range
of 94-107, with the single exception of a low value of 87 for Spain
found by Nieto Alegre et al (1967). The variations between and
within the countries are probably due principally to differences in
sampling accuracy and procedures and to differences in living
standards. Differences in sampling accuracy and procedures can
occur because of the difficulty of obtaining representative samples
and to differences in whether the mentally retarded are included.
In the case of children, those in private schools may or may not be
included in the samples. Sampling differences are probably largely
responsible for a number of the discrepancies in the means obtained
from the same country, e.g. the two studies of general intelligence
in Australia give means of 95 and 104, and the three studies of
France give means of 98, 104 and 94.
The largest discrepancy in the table is between the mean IQ of
87 for Spain obtained by Nieto Alegre et al and the mean of 98
obtained by Buj. This probably arises from a sampling difference
between the two studies. Nieto Alegre et al obtained their sample
from military conscripts drawn from the whole of Spain, whereas Buj
drew his samples for Spain and other countries from the populations
of the capital cities. While the sampling procedure adopted by Buj
seems reasonable, it is probable that in less economically
developed countries like Spain with a rather backward peasant
population there are considerable differences between the mean IQs
in the rural areas and in cities. In fact in the Nieto Alegre study
there was a range of approximately 15 IQ points between the means
of the conscripts from the poorest rural regions and the most
prosperous and more urbanized centers. As countries have become
more industrialized the numbers of their rural peasantry have
declined and rural-urban differences in intelligence have largely
disappeared. Thus Scotland was a largely urbanized country by the
1930s and at this time there was virtually no difference in mean IQ
between urban and rural children (Scottish Council for Research in
Education, 1939).
In addition to differences in sampling, some of the differences
between these Caucasoid populations may also be ascribed to
differences in living standards. There is a wide range of these
among this set of nations. For instance, in Spain which produced
the lowest mean IQ of 87 for military conscripts tested in 1965,
the per capita income in that year was 770 US dollars as compared
with $2,003 in Britain and $4,058 in the United States (United
Nations, 1970). Low incomes have an adverse effect on intelligence
because poor people have less to spend on nutritious foods and tend
to have less leisure to give their children cognitive stimulation.
Nevertheless, in spite of these considerable differences in living
standards, the overall picture of the results summarized in Table 1
is one of fairly close similarity of mean IQs among these diverse
Caucasoid populations.
The last entries in Table 1 are for the IQs of Indians derived
from the Indian subcontinent, South Africa and Britain. The mean of
86 in India is derived from a review by Sinha (1968) of the results
of 17 studies of children aged between 9 and 15 years and totalling
in excess of 5,000. Mean IQs lie in the range of 81 to 94, with an
overall mean of approximately 86. But ethic Indians in Britain
obtain a mean of 96 which is within the range of other Caucasoid
populations. Their verbal IQ of 89 is depressed, but this is
probably because their families are recent immigrants and have not
yet mastered the language. The British results suggest that when
Indians is are reared in an economically developed environment
their intelligence level is about tile same as that of European
Caucasoids.
Mongoloids
The Mongoloid peoples are those indigenous to north east Asia,
north of the Himalayas and east of the Yenisey river. Their mean
IQs are set out in Table 2. It will be seen that for general
intelligence the Mongoloid peoples tend in the majority of studies
to obtain somewhat higher means than Caucasoids. This is the case
in tile United States, Canada, Europe, Japan, Hong Kong, Taiwan,
Singapore and The People's Republic of China. The range is from 97
to 110, with a mean of around 106. The lowest figure is the mean of
97 obtained by Stevenson et al for Japanese 6 year olds. One
explanation for this result is probably that Mongoloids tend to be
late maturers. There is a good deal of evidence for this reviewed
in Lynn (1987). It will be noted that the same investigators
obtained a mean of 102 for Japanese 11 year olds. A further factor
is that Stevenson obtained his American comparison sample from the
city of Minneapolis in Minnesota and the mean Caucasoid IQ in
Minnesota is 105 (Flynn, 1980, p. 107). This means that 5 IQ points
should be added to all of Stevenson's Japanese means.
There is some dispute about the mean IQs of ethnic Mongoloids in
the United States. Vernon (1982) reviewed the literature and
concluded that the mean non-verbal IQ (general intelligence) was
around 110 and the verbal IQ 97. These figures have been questioned
by Flynn (1989) who maintains that the respective means are
approximately 100 and 97. The best single study of American ethnic
Mongoloids appears to be the Coleman et al (1966) report of five
age groups spanning the years 6-16 from which Flynn's figures are
derived. But there are problems with the Coleman study. One is that
in this and other studies the category of Orientals may include
Filipinos, whose mean IQ is about 85 (Flynn, 1991) and who
therefore pull down the mean of ethnic Chinese end Japanese.
Filipinos constitute about 20 per cent of American Orientals and if
these are taken out of the Coleman sample the remainder who are
largely ethnic Chinese and Japanese obtain a mean non-verbal IQ of
103 and a mean verbal IQ of 98.
A further problem in the Coleman data concerns the nature of the
tests of "non verbal ability". Coleman himself is careful to state
that the non verbal tests used in his study were not measures of
intelligence. The tests were of math ability largely set out in
verbal format and this will have given the tests a verbal bias and
handicapped Orientals (Coleman 1990). Probably the Coleman non
verbal ability tests should not be considered as good measures of
general intelligence or Spearman's g. The weaknesses of the
American studies of ethnic Orientals is that hardly any of them
provide a good measure of visuospatial abilities or of Spearman's
g.
If Flynn should prove to be correct it would appear that the
mean IQ of American ethnic Orientals is a little below that of
Mongoloids in the countries of the Pacific rim. The explanation for
this may be that the early Chinese and Japanese immigrants from
whom the majority of ethnic Orientals are derived may have been
below the average intelligence levels of their parent populations
in Asia. The early immigrants came largely as laborers to build the
railways and do other unskilled work developing the infrastructure
of the west coast. This not particularly desirable work may have
attracted those of less than average ability. If this is so, the
high educational and occupational achievements of ethnic Orientals
in the United States may be due to high work motivation rather than
high intelligence levels.
A striking feature of the results for Mongoloids is that their
verbal IQs are consistently lower than their visuospatial IQs. In
most studies the differences are substantial amounting to between
10 to 15 IQ points. This pattern is present in Japan, Hong Kong,
the United States and Canada. It has also been found among ethnic
Japanese in Hawaii although these data are not presented in a form
from which mean IQs can be calculated (Nagoshi and Johnson,
1987).
This difference is also picked up in the United States in
performance on the Scholastic Aptitude Test (SAT), on which ethnic
Orientals invariably do better than Caucasians on the mathematics
test (largely a measure of general intelligence and visuospatial
ability) but less well than Caucasians on the verbal test (Weiner,
1988). A further manifestation of the strong visuospatial and weak
verbal abilities of ethnic Oriental Americans lies in their
tendency to do well in professions like science, architecture and
engineering which call for strong visuospatial abilities and poorly
in law which calls for strong verbal abilities. This pattern of
occupational achievement has been well documented by Weyl
(1969,1989) in his studies of the achievements of the major
American ethnic populations. His method involves the analysis of
the frequencies of ethnic names among those who have achieved
occupational distinction calculated in relation to their
frequencies in the general population. Thus he finds that common
Chinese names like Wong are greatly overrepresented in American Men
and Women of Science, as compared with their frequency in the
general population, but under represented in Who's Who in American
Law. On the basis of this method he constructs a performance
co-efficient for which average achievement is 100. A co-efficient
of 200 means that an ethnic group appears twice as frequently in
reference works of occupational distinction as would be expected
from its numbers in the total population, while a co-efficient of
50 means that it appears half as often. In his first study he finds
that ethnic Chinese obtained performance coefficients of 506 in
architecture, 303 in engineering and 438 in science but only 54 in
law (Weyl, 1969). His second study on later data confirms this
pattern for the 1980s, when ethnic Chinese obtained a performance
co-efficient for science of 620, while for law their performance
co-efficient was only 24.
It is easy to understand how this remarkable disparity arises.
Adolescents typically discover that they tend to be good at some
things and poor at others. There is a natural tendency for young
people to concentrate on those activities they are good at, be they
sciences, languages, arts, music, sport or whatever, and to make
their careers in them. The reason that different people are good at
different things depends partly on genetic and partly on
environmental differences. The widespread appearance of the strong
visuospatial -- weak verbal ability pattern among Mongoloids in so
many diverse geographical locations suggests that it has a genetic
basis and that this is responsible for their striking
over-achievement in the sciences and architecture and
under-achievement in law.
Negroids
The mean IQs of Negroids have invariably been found to be
substantially lower than those of Caucasoids. Many studies have
been done in the United States and by the mid- 1960's Shuey (1966)
was able to present a summary of 362 investigations. The overall
mean IQ of American Negroids was approximately X5. Subsequent
studies in the United States such as those of Coleman (1966),
Broman, Nichols and Kennedy (1975) and others have confirmed that
this is about the right figure.
As a result of these studies it is sometimes assumed that the
mean IQ of all Negroids is approximately 85 or 1 standard deviation
below that of Caucasoids. However, it has to be noted that almost
all American Negroids are Negroid-Caucasoid hybrids (Reed, 1989)
and the same is probably true of most Negroids in the West Indies
and Britain. To obtain mean IQs of pure Negroids it is necessary to
take samples in Africa. For this reason mean IQs for pure African
Negroids are listed separately in Table 3 from Negroid-Caucasoid
hybrids in the United States, Britain, the West Indies and South
Africa.
The first good study of the intelligence of pure African
Negroids was carried out in South Africa by Fick (1929). He used
the American Army Beta Test, a non verbal test devised in the
United States in the First World War for testing recruits who could
not speak English, and administered it to 10-14 year old Caucasoid,
Negroid and Colored (NegroidCaucasoid hybrids) school children. In
relation to the Caucasoid mean of 100, based on more than 10,000
children, largely urban pure Negroid children obtained a mean IQ of
65, while urban Colored children obtained a mean IQ of 84. It is
interesting to note that these South African Coloreds or
Negroid-Caucasoid hybrids obtained a mean IQ virtually identical to
that of American Caucasoid-Negroid hybrids.
The other studies of the IQs of pure Negroids summarized in
Table 3 show means in the range 65-81. Vernon tested his small
sample in Kampala with a number of tests and the overall mean was
about 80, but this sample was drawn from an academic secondary
school and the result suggests that the mean for the population
would be around 70. The best single study of the Negroid
intelligence is probably that of Owen (1989), who presents results
for 1093 16 year olds in the eighth grade who had been in school
for around 8 years and should have been well versed in paper and
pencil tests. The test used was the South African Junior Aptitude
which is well constructed and standardized and provides measures of
verbal and non verbal reasoning, spatial ability, verbal
comprehension, perceptual speed and memory. The mean IQ of the
sample in comparison with Caucasoid South African norms is 69. It
is also around the median of the studies listed in Table 3. It is
proposed therefore to round this figure up to 70 and take this as
the approximate mean for pure Negroids.
Negroid-Caucasoid Hybrids
As noted, virtually all American Negroids are hybrids with some
Caucasoid ancestry. The same is probably the case with West Indian
and British Negroids. Although this has never been documented, West
Indian Negroids lived as slaves on white owned plantations from the
17th to the 19th century in similar conditions to those of Negroids
in the United States. There was undoubtedly a certain amount of
interbreeding between white estate owners and Negroid slaves, which
gave rise to a number of Negroid-Caucasoid hybrids whose existence
as a considerable class was noted by Anthony Trollope in his Tour
of the West Indies.
The results for Negroid-Caucasoid hybrids are shown in Table 4.
For the United States, seven major post Shuey (1966) studies are
listed because of their special interest by virtue of the large
number of subjects, because they yield IQs for the verbal and
visuospatial abilities, or because they are derived from young
children. These show that the Negroid mean IQ of approximately 85
is present among children as young as 2-6 year olds.
In Britain the three major studies of Negroids obtained mean IQs
of 86, 94 and 87, broadly similar to those in the United States.
Figures are available for two of the Caribbean islands, namely
Barbados (mean IQ = 82) and Jamaica (mean IQ = 66-75).
The Negroid-Caucasoid differences appear to be of about the same
magnitude for general intelligence and the verbal and visuospatial
abilities. Detailed studies by Jensen and his colleagues have shown
that when samples are carefully matched the Negroid-Caucasoid
differences are greatest for general intelligence (Spearman's g)
and for the visuospatial abilities and less for verbal ability
(Jensen and Reynolds, 1982; Reynolds and Jensen, 1983; Naglieri and
Jensen, 1987). Nevertheless, the broad picture, taking the results
as a whole, is that the three abilities are of approximately equal
magnitude. This also appears to be the case in South Africa
according to the results of Owen.
Amerindians
The results of studies of the intelligence of Amerindians are
summarized in Table 5. The mean general IQs have invariably been
found to be somewhat below that of Caucasoids. The largest study is
that of Coleman et al (1966) which obtained a mean of 94, but a
number of studies have reported means in the 70-90 range. The
median of the 15 studies listed is 89 which can be taken as a
reasonable approximation, indicating that the Amerindian mean IQ
falls someway between that of Caucasoids and Negroid-Caucasoid
hybrids. The same intermediate position is occupied by Amerindians
in performance on the Scholastic Aptitude Test (Weiner, 1988).
In addition, all the studies of Amerindians have found that they
have higher visuospatial than verbal IQs. The studies listed are
those where the Amerindians speak English as their first language,
so this pattern of results is unlikely to be solely due to the
difficulty of taking the verbal tests in an unfamiliar language.
The verbal-visuospatial disparity is also picked up in the
Scholastic Aptitude Test, where Amerindians invariably score higher
on the mathematical test than on the verbal (Weiner, 1988).
The strong visuospatial-weak verbal pattern of abilities in the
Amerindians resembles that of the Mongoloids, although in the
Mongoloids the whole ability profile is shifted upwards by some
10-15 IQ points. This similarity is not altogether surprising in
view of the close genetic relationship of the two races,
Amerindians being an offshoot of the Mongoloids who crossed the
Bering Straits from north east Siberia into Alaska at some time in
prehistory. The similarity of the cognitive profile of tile two
races suggests that this profile was present in the common stock
from which both contemporary races at-e derived, and that some
factor raised the intelligence levels in the Mongoloids following
the geographical differentiation of the two races.
South East Asians
The South East Asian races comprise Polynesians, Micronesians,
Melanesians, Maoris and Australian Aborigins. The results of
intelligence test studies of these subs-aces are shown in Table 6.
Apart from tile low mean of 67 tot a small sample of Australian
Aborigine children all the mean Iqs lie in the range of 80-95. The
one study to include measures of general, verbal and visuospatial
abilities for New Zealand Maoris shows that this group does not
share the strong visuospatial-weak verbal ability profile of
Mongoloids and Amerindians Although the intelligence of this group
of peoples has not been extensively researched there are sufficient
studies to suggest a mean IQ of about 90.
Racial Differences in Reaction Times
It has often been argued that the racial differences in
intelligence test performance may be due to the tests being biased
or to a variety of environmental factors such as differences in
education experience of clearing with visual representations
motivation, attitudes towards test taking and nutrition. The
alternative theory is that these differences have a genetic basis.
In order to test for which of these different explanations is
correct, a study has been carried out to determine whether the
racial differences in intelligence are also present in reaction
times. The rationale of the study is that reaction times provide a
measure of the brains neurological efficiency in dealing with very
simple tasks and are unaffected by education, motivation and other
environmental factors with the possible exception of extreme
malnutrition.
It has been shown in a number of studies that reaction times are
positively associated with intelligence and the explanation widely
accepted for this association is that reaction times provide a
measure of the neurological efficiency of the brain in analysis and
decision making (Jensen, 1982; Eysenck, 1982). Hence if there are
racial differences in reaction times of the same kind as those
present in intelligence test performance, it can be inferred that
these differences lie at the neurological level and probably
reflect genetic differences.
Reaction times consist of the speed with which a subject reacts
to simple stimuli. Normally a light comes on and the subject has to
press a button to turn it off. Reaction time tasks can be varied to
present different degrees of difficulty. In the present study three
reaction time tasks were used of different degrees of difficulty.
In the simplest task a single light comes on and the subject moves
his hand to switch it off. This response normally takes around half
a second. In more complex situations, one of several lights comes
on and has to be switched off. These are known as choice reaction
times and take a little longer. In a still more complex task, three
lights come on of which two are close together and one stands
apart. Here the subject has to judge which is the light that stands
apart and switch it off. This is known as the odd man out task. It
is more difficult than the simpler reaction time tasks and
typically takes about twice as long.
All three reaction time tasks were used in the present study. In
addition, the apparatus used in the investigation was designed to
measure two separate processes in reaction time tasks known as
movement times and decision times. In these tasks the subject has
to make a decision about what to do (decision times) and then
execute the decision by moving the finger to switch off the light
(movement times). Both these times were recorded automatically on
disks by a microcomputer.
The subjects used in the study consisted of 9 year old children
representative of the three major races of Mongoloids, Caucasoids
and Negroids. The Mongoloids were obtained from Hong Kong and
Japan, the Caucasoids from Britain and Ireland and the Negroids
from South Africa. All the children were drawn as socially
representative samples from typical public primary schools in their
respective countries with the exception of the Irish children who
came from rural areas and whose mean IQ was rather lower than would
otherwise have been expected.
In all the five samples decision times, movement times and
variabilities were negatively correlated with intelligence. Further
details of tile reaction time apparatus, testing procedures and
analyses of the relationship between tile reaction time measures
and intelligence for the samples are given in Shigehisa and Lynn
(1991), Chan, Eysenck and Lynn (1991) and Lynn and Holmshaw
(1991).
Summary statistics for tile five samples giving the numbers
tested, mean IQs, means for tile 12 reaction time measures and
standard deviations for tile entire sample are shown in Table 7.
The last column of the table gives product moment correlations
between tile Progressive Matrices and the 12 reaction time
measures. It will be seen that the Hong kong and Japanese children
obtained tile highest mean IQs, fastest decision times and low
decision time variabilities, the British and Irish children were
inter-mediate, while tile South African Negroids obtained the
lowest means on tile Progressive Matrices, slowest decision times
and highest variabilities. All tile correlations are high and five
of tile six are statistically significant.
The movement times of the five populations do not show any
consistent overall relationship with Progressive Matrices scores.
It is however interesting to note that tile Negroid children tend
to have fast movement times. In the complex and odd man out tasks
their movement times are significantly faster than those of British
Irish and Chinese children.
It is known that tile speed of reaction times is genetically
determined to a significant extent. This has been shown by Vernon
(1989) in a study of 50 identical and 52 nonidentical twins, which
produced a heritability coefficient of .51 for reaction times.
Somewhat similar results have been reported by Ho, Baker and
Decker- (1988) for two other speed of information processing tasks
which gave heritability coefficients of .47 and .24. These authors
have also shown that the positive correlation between treasures of
speed of information processing and intelligence arises from common
genetic processes suggesting that common genetically controlled
neurological mechanisms are involved in the performance of both
types of task.
It is therefore considered that the most reasonable
interpretation of the Mongoloid-Caucasoid-Negroid results is that
these reflect genetic differences between the three racial groups.
It is not considered likely that educational differences could be
involved because of the extreme simplicity of the tasks.
Motivational differences are improbable, because reaction times
seem unaffected by motivation (Jensen, 1982). It might be thought
that nutritional differences might be involved.
However, the fact that the Negroid children performed faster
than the Caucasoid on movement times makes it unlikely that poor
nutrition could have reduced neural conduction rates. We are
therefore left with genetically determined differences in
information processing capacities as the most probable explanation
of the Mongoloid-Caucasoid-Negroid differences in decision
times.
Contributions to Civilization
A third source of evidence on racial differences in intelligence
lies in the degree to which the various races have made significant
intellectual, scientific and technological discoveries and
inventions. The argument is that these advances are likely to be
made by a few outstanding and highly intelligent individuals. There
will be more of these in a population where the average level of
intelligence is high, and hence the intelligence levels of
populations and whole races can be inferred from their intellectual
achievements.
The first writer to advance this argument was Galton (1869) but
he limited his analysis to the Greeks of the classical period,
England and Scotland, the Negroids and the Australian Aborigines.
His conclusion was that the Greeks produced the greatest number of
intellectual advances and could therefore be considered the most
intelligent population. He placed the Scots marginally above the
English, and a long way below these he placed the Negroids and the
Aborigines.
Galton's treatment of the problem was sketchy but it provided
the initial idea on which others were to build. The most extensive
analysis of this kind was carried out by Baker (1974). He first set
up twenty one criteria by which the achievements of early
civilizations could be judged. These were as follows:
1. In the ordinary circumstances of life in public places, they
cover the greater part
of the trunk with clothes.
2. They keep the body clean and take care to dispose of its
waste products.
3. They do not practice severe mutilation or deformation of the
body, except for
medical reasons.
4. They have knowledge of building in brick or stone, if the
necessary materials are
available in their territory.
5. Many of them live in towns or cities, which are linked by
roads.
6. They cultivate food-plants.
7. They domesticate animals and use some of the larger ones for
transport (or have
in the past so used them), if suitable species are available.
8. They have knowledge of the use of metals, if these are
available.
9. They use wheels.
10. They exchange property by tile use of money.
11. They order their society by a system of laws, which are
enforced in such a way
that they ordinarily go about their various concerns in times of
peace without
danger of attack or arbitrary arrest.
12. They permit accused persons to defend themselves and to
bring witnesses for their
defence.
13. They do not use torture to extract information or for
punishment.
14. They do not practice cannibalism.
15. Their religious systems include ethical elements and are not
purely or grossly
superstitious.
16. They use a script (not simply a succession of pictures) to
communicate ideas.
17. There is some facility in the abstract use of numbers,
without consideration of
actual objects (or in other words, at least a start has been made
in mathematics).
18. A calendar is in use, accurate to within a few days in the
year.
19. Arrangements are made for the instruction or the young in
intellectual subjects.
20. There is some appreciation of the fine arts.
21. Knowledge and understanding are valued as ends in
themselves.
Having set up these criteria, Baker proceeded to analyze the
historical record of the races to ascertain which have originated
civilizations. His conclusion was that the Caucasoid peoples
developed all 21 components of civilization in four independent
locations. These were the Sumerian in the valley of the Tigris and
the Euphrates, the Cretian, the Indus Valley, and the ancient
Egyptian. The Mongoloids also developed a full civilization in the
Sinic civilization in China. The Amerindians achieved about half of
the 21 components in the Maya society of Guatemala, a little less
in the Inca and Aztec societies, but these peoples never invented a
written script, the wheel (except possibly in children's toys), the
principle of the arch in their architecture, metal working, or
money for the exchange of goods. The Negroids and the Australian
aborigines achieved virtually none of the criteria of
civilization.
While Baker confined his analysis to the achievements of the
races in originating civilizations, there can be little doubt that
the same race differences appear in the historically later
development of more advanced cultures. During the last 2,000 years
the many discoveries that constitute developed peoples have been
made only by the Caucasoid and Mongoloid peoples. For the first
sixteen hundred or so years of this period a case can be made out
that the Mongoloid civilization in China was marginally ahead. The
Han period of around 200-100 BC saw the introduction of written
examinations for candidates for the mandarin civil service, an idea
which was considered an advance when it was introduced into Britain
some 2,000 years later (Bowman, 1989). Printing was invented in
China by about 800, some 600 years before it was developed in
Germany. When Marco Polo visited China about the year 1300 he was
amazed at the quality of civilization in the numerous prosperous
cities and particularly at the use of paper money, a concept not
introduced into the general use in Europe until the nineteenth and
twentieth centuries. The Chinese discovered gunpowder about the
year 1050 and developed the technology for using it for guns and
not only, as popularly supposed, for fireworks. They were the first
to invent the principle of the magnetic compass. Their technology
for the manufacture of high quality porcelain was well ahead of
anything in Europe until the late eighteenth century. Details of
these and many other Chinese scientific and technological
achievements are given in Needham (1954).
During the last five centuries the Caucasoid peoples of Europe
and latterly of North America have pulled ahead of the Mongoloids
in science and technology. This is probably because China has been
run as a single bureaucratic empire in which innovation has been
discouraged first under the emperors and more recently under the
communists while Japan was isolated from outside influences until
relatively recently. Europe, in contrast, has been divided into
numerous states, many of which afforded a high degree of personal
freedom of thought, expression and technological innovation, and
between which there was open communication. Nevertheless, although
the Europeans have generally been ahead of the Mongoloids during
the last five centuries, since 1950 the Japanese have provided a
strong challenge and have surpassed the West in the production of a
number of high quality technological goods.
A useful source for evaluating the contributions of the human
races to scientific and technological achievements is available in
Asimov's (1989) Chronology of Science and Discovery. This lists
approximately 1,500 of the most important scientific and
technological discoveries and inventions which have ever been made.
The first three are bipedality the manufacture of stone tools and
the use of fire which antedate the evolution of the races.
Thereafter every single invention and discovery was made by the
Caucasian or Mongoloid peoples. This compilation confirms the
historical record. Who can doubt that the Caucasoids and the
Mongoloids are the only two races that have made any
significant contribution to civilization.
Conclusion
The studies of racial differences in intelligence test results
reaction times and scientific and technological discoveries show a
high degree of consistency. All three sources of evidence indicate
that the two races with the highest intelligence levels are the
Mongoloids and the Caucasoids. These are followed by the
Amerindians, while the south east Asian races and the Negroids are
ranked lowest. The intelligence test results and the reaction times
tend to indicate that average Mongoloid intelligence levels are a
little higher than those of Caucasoids, but the difference is
relatively small as compared with other racial differences.
The general consistency of the results from the three sources of
evidence, and the consistency of the different intellectual
achievements of the races over a long historical period, points to
a substantial genetic determination for these differences. If
genetic factors were not involved, there would have been much
greater variation over time and place and the observed
consistencies would not be present. Whatever criteria are adopted,
the Caucasoids and the Mongoloids are the two most intelligent
races and the historical record shows that this has been the case
for approximately the last 5,000 years.
The environmentalist may argue that the Negroid peoples in
Africa, the Caribbean, the United States and Britain, and the
Amerindians, Maoris and Australian aborigines, all live in socially
and economically impoverished conditions, as compared with
Caucasoids and Mongoloids, and that these conditions are
responsible for some or perhaps all of their low intelligence. This
argument can be met by the concept of genotype-environment
correlation, originally proposed by Plomin, De Fries and Loehlin
(1977) and developed by Scarr and McCartney (1983).
There are two processes of genotype-environment correlation
which are relevant to the present problem. The first is "passive"
and has the effect that children tend to be reared in environments
which are e cot related with their own genetic potentialities. The
principle applies for any trait which has a heritability, and this
is undoubtably true of intelligence, and in the case of
intelligence means that intelligent parents transmit the
characteristic genetically through their genes and environmentally
through tile advantageous environment which they provide for their
children The two modes of transmission have the effect that
intelligent children tend to be reared in
intelligence-enhancing
environments. This brings the genotypes and the advantageous
environments into positive correlation and implies that those
reared in advantageous environments tend to have superior
genotypes. This applies, for instance, to middle class children as
compared with working class children, and can also, arguably, be
applied to Caucasoid and Mongoloid children as contrasted with
those of other races.
There is a second "active" type of genotype-environment
correlation which states that people play an active role in
creating their own environments. Genotypically intelligent peoples
are able to create a socially and economically affluent environment
to an extent which cannot be done by less intelligent peoples.
Scarr and McCartney call this "niche building", and the two peoples
who have been successful in building socially and economically
developed niches in which to live and rear their children have been
the Caucasoids and the Mongoloids.
The argument frequently advanced that poor social and economic
conditions are responsible for the lower intelligence of the
Negroids, Aborigines and Amerindians places tile cart before the
horse. It assumes that the impoverished environments of these
peoples are simply the result of external circumstances over which
these peoples themselves have no control. Such a claim does not
stand up to examination. There are so many cases which it cannot
explain, such as the achievements of Chinese, Japanese, Korean and
Vietnamese immigrants in the United States and of Indians in
Britain and Africa. The only plausible explanation for why these
peoples have succeeded where others, initially more advantageously
placed, have failed is that they have the right genotypes for
building socially and economically prosperous environments for
themselves and their families.
Appendix: Notes on the Calculation of IQs
One of the principal problems in the calculation of the mean IQs
for the various racial populations concerns the date at which the
data were collected. Mean IQs in the economically advanced nations
have been increasing during the last half century (Lynn and
Hampson, 1986; Flynn, 1987). This poses the problem of whether an
adjustment should be made for this increase in studies where a test
standardized in the United States, Britain, Australia or New
Zealand has been administered some years later to another
population. The adjustment involves making an addition to the
American, British or Australasian means to allow for the time
interval between the two test administrations. The effect is
generally to increase Caucasoid IQs in relation to those of other
peoples. The increases are however quite small and do not remove
the higher means obtained by Mongoloid populations, as shown in
Lynn (1987).
For the present paper it was decided not to make such
adjustments on two grounds. Firstly, the rates of secular increase
of intelligence vary widely from about 1 to 6 IQ points per decade
in studies of different age groups and different tests. It is
therefore impossible to obtain any precise estimate of what
adjustment would be appropriate for many of the tests. Secondly,
the great majority of the studies employ tests initially
standardized in the United States, Britain, Australia or New
Zealand. These countries have high standards of living in relation
to other populations and therefore enjoy some environmental
advantage for the development of intelligence. This advantage is to
some degree counterbalanced by the earlier administration of the
tests. The decision was therefore made not to adjust the results
for other populations for the time differential between tile two
test administrations but to report the mean IQs as originally
published. However, tests given to racial groups in the same
country as the standardization samples have been reduced to allow
for tile secular increase in the mean IQ of the base population.
This correction applies to the Kline and Lee (1972) Canadian
Chinese sample, whose mean IQs are reduced by 7 IQ points to allow
for the secular increase of intelligence 1947-1970; and to the
Belgian Korean sample whose IQs are reduced by 10 points to allow
for a secular increase of intelligence in Belgium 19541983.
Figures for general intelligence are derived either from
nonverbal reasoning tests such as the Progressive Matrices and the
Culture Fair, or from full scale Wechsler IQs. In some studies only
verbal and performance Wechsler IQs are reported and where this is
tile case these have been averaged to give an approximate figure
for the full scale IQ. Where means for Wechsler subtests are
reported, tile verbal IQs are calculated from Vocabulary,
Information, Comprehension, Similarities and Arithmetic, and
Visuospatial IQs from Block Design, Object Assembly, Picture
Arrangement, Picture Completion and Mazes. The reason for this is
that factor analysis has shown that these are tile best measures of
tile two abilities (Jensen and Reynolds, 1982). In the case of
non-American standardizations of tile Wechslers, IQs are calculated
from the WISC tests by reading tile means off tile standardization
tables and converting to American IQs. Buj's IQs are given in
relation to a British mean of 100.
Table 1: Mean IQs of various Caucasoid populations
| Caucasoids |
Age |
Number |
Test |
| Sample |
| United States |
- |
- |
- |
| Austria |
adults |
187 |
Culture Fair |
| Australia |
9-13 |
35,000 |
Otis
|
|
Australia
|
6 |
600 |
Coloured PM |
| Australia |
8-12 |
400 |
WISC |
| Belgium |
adults |
247 |
Culture Fair |
| Belgium |
5-15 |
600 |
WISC |
| Belgium |
10-16 |
920 |
Culture Fair |
| Britain |
13-15 |
10,000 |
Differential Aptitude |
| Britain |
adults |
1,405 |
Culture Fair |
| Bulgaria |
adults |
215 |
Culture Fair |
| Czechoslovakia |
adults |
363 |
Culture Fair |
| Czechoslovakia |
6 |
832 |
Coloured PM |
| Denmark |
12 |
628 |
Progressive Matrices |
| Denmark |
adults |
122 |
Culture Fair |
| Finland |
adults |
120 |
Culture Fair |
| France |
adults |
1,320 |
Culture Fair |
| France |
6-9 |
618 |
Coloured PM |
| Germany, DR |
7-11 |
454 |
Coloured PM |
| Germany FR |
6 |
3,607 |
Coloured PM |
| Germany FR |
adults |
1,572 |
Culture Fair |
|
Caucasoids
|
Intelligence |
|
|
General |
Verbal |
Visuo-spatial |
| Sample |
| United States |
100 |
100 |
100 |
| Austria |
101 |
- |
- |
| Australia |
95 |
| Australia |
104 |
| Australia |
- |
- |
104 |
| Belgium |
98 |
| Belgium |
- |
- |
101 |
| Belgium |
104 |
| Britain |
101 |
102 |
102 |
| Britain |
100 |
| Bulgaria |
94 |
| Czechoslovakia |
98 |
| Czechoslovakia |
104 |
| Denmark |
100 |
| Denmark |
99 |
| Finland |
96 |
| France |
104 |
| Germany, DR |
100 |
| Germany FR |
102 |
| Germany FR |
107 |
|
Caucasoids
|
| Sample |
Source |
| United States |
| Austria |
Buj. 1981 |
| Australia |
McIntyre, 1938 |
| Australia |
Reddington and Jackson, 1980 |
| Australia |
Radcliffe and Trainer, 1969 |
| Belgium |
Buj, 1981 |
| Belgium |
Berte, 1961 |
| Belgium |
Goosens, 1962 |
| Britain |
Lynn, Hampson and Iwawaki, 1987 |
| Britain |
Buj, 1981 |
| Bulgaria |
Buj, 1981 |
| Czechoslovakia |
Buj, 1981 |
| Czechoslovakia |
Raven, 1986 |
| Denmark |
Veileskov, 1968 |
| Denmark |
Buj, 1981
|
| Finland |
Buj, 1981 |
| France |
Buj, 1981 |
| France |
Bourdier, 1964 |
| Germany, DR |
Kurth, 1969 |
| Germany FR |
Schmidtke, Schaller & Becker, 1978 |
| Germany FR |
Buj, 1981
|
|
Caucasoids
|
| Sample |
Age |
Number |
Test |
| Greece |
adults |
220 |
Culture Fair |
| Hungary |
adults |
260 |
Culture Fair |
| Ireland |
adults |
75 |
Culture Fair |
| Italy |
adults |
1,380 |
Culture Fair |
| Italy |
10-16 |
614 |
Progressive Matrices |
| Netherlands |
adults |
333 |
Culture Fair |
| New Zealand |
9-15 |
26,000 |
Otis |
| New Zealand |
8-16 |
2,635 |
Progressive Matrices |
| Norway |
adults |
100 |
Culture Fair |
| Poland |
adults |
835 |
Culture Fair |
| Poland |
10 |
213 |
WISC |
| Portugal |
adults |
242 |
Culture Fair |
| Romania |
6 |
300 |
Coloured PM
|
| Scotland |
11 |
1,000 |
Stanford Binet
|
| Scotland |
11 |
1,215 |
Terman Merrill
|
| Spain |
10 |
113,749 |
Progressive Matrices
|
| Spain |
adults |
848 |
Culture Fair |
| Sweden |
adults |
205 |
Culture Fair |
| Sweden |
6-15 |
1,106 |
WISC |
| Switzerland |
adults |
163 |
Culture Fair |
| Yugoslavia |
adults |
525 |
Culture Fair |
| India |
children |
5,000 |
various |
| British Indians |
11 |
170 |
British Ability |
| S.African Indians |
16 |
1,063 |
Junior Aptitude |
| Caucasoids |
Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
| Greece |
97 |
| Hungary |
99 |
| Ireland |
78 |
| Italy |
101 |
| Italy |
100 |
| Netherlands |
107 |
| New Zealand |
99 |
| New Zealand |
102 |
| Norway |
100 |
| Poland |
106 |
| Poland |
107 |
| Portugal |
101 |
| Romania |
95 |
| Scotland |
99 |
| Scotland |
102 |
| Spain |
87 |
| Spain |
98 |
| Sweden |
104 |
| Sweden |
- |
- |
104 |
| Switzerland |
101 |
| Yugoslavia |
104 |
| India |
86 |
| British Indians |
96 |
89 |
| S.African Indians |
85 |
| Caucasoids |
Intelligence Source |
| Sample |
| Greece |
Buj, 1981 |
| Hungary |
Buj, 1981 |
| Ireland |
Buj, 1981 |
| Italy |
Buj, 1981 |
| Italy |
Tesi and Young, 1962 |
| Netherlands |
Buj, 1981 |
| New Zealand |
Redmond and Davies, 1940 |
| New Zealand |
Raven and Court, 1989 |
| Norway |
Buj, 1981 |
| Poland |
Buj, 1981 |
| Poland |
Firkowska et al 1978 |
| Portugal |
Buj, 1981 |
| Romania |
Zahirnic et al 1974 |
| Scotland |
Scottish Council, 1933 |
| Scotland |
Scottish Council, 1949 |
| Spain |
Nieto-Alegre et al 1967 |
| Spain |
Buj, 1981 |
| Sweden |
Buj, 1981 |
| Sweden |
Scandinaviska Test for laget, 1970 |
| Switzerland |
Buj, 1981 |
| Yugoslavia |
Buj, 1981 |
| India |
Sinha, 1986 |
| British Indians |
Mackintosh and Mascie-Taylor, 1985 |
| S.African Indians |
Owen, 1989 |
Table 2: Mean IQs of various Mongoloid populations
| Mongoloids |
| Sample |
Age |
Number |
Test |
| Japan |
5-16 |
1,070 |
WISC |
| Japan |
6 |
240 |
Vocabulary-spatial |
| Japan |
11 |
240 |
Vocabulary-spatial |
| Japan |
2-8 |
550 |
McCarthy Scales |
| Japan |
4-6 |
600 |
WPPSI |
| Japan |
6-16 |
1,100 |
WISC-R |
| Japan |
13-15 |
178 |
Differential Aptitude |
| Japan |
13-14 |
216 |
Kyoto-NX |
| Japan |
3-9 |
347 |
Columbia MMS |
| Japan |
9 |
444 |
Progressive Matrices |
| Hong Kong |
6-15 |
4,500 |
Progressive Matrices |
| Hong Kong |
10 |
197 |
PM, Space Relations, Fluency |
| Hong Kong |
9 |
376 |
Cattell Culture Fair |
| Hong Kong |
6 |
4,858 |
Coloured PM |
| Mongoloids |
Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
| Japan |
- |
- |
103 |
| Japan |
97 |
89 |
105 |
| Japan |
102 |
98 |
107 |
| Japan |
100 |
92 |
108 |
| Japan |
103 |
98 |
108 |
| Japan |
103 |
101 |
107 |
| Japan |
104 |
- |
114 |
| Japan |
101 |
100 |
103 |
| Japan |
110 |
- |
- |
| Japan |
110 |
- |
- |
| Hong Kong |
110 |
- |
- |
| Hong Kong |
108 |
92 |
114 |
| Hong Kong |
113 |
- |
- |
| Hong Kong |
116 |
- |
|
Mongoloids
|
| Sample |
Source |
| Japan |
Lynn, 1977 a |
| Japan |
Stevenson, Stigler, Lee, Lucker Kitamura and Hsu, 1985 |
| Japan |
- " - |
| Japan |
Lynn and Hampson, 1986 a |
| Japan |
Lynn and Hampson, 1986 b |
| Japan |
Lynn and Hampson, 1986 c |
| Japan |
Lynn, Hampson and Iwawaki, 1987 |
| Japan |
Lynn, Hampson and Bingham, 1987 |
| Japan |
Misawa, Motegei, Fujita and Hattori, 1984 |
| Japan |
Shigehisa and Lynn, 1991 |
| Hong Kong |
Lynn, Pagliari and Chan, 1988 |
| Hong Kong |
Lynn, Pagliari and Chan, 1988 |
| Hong Kong |
Lynn, Hampson and Lee, 1988 |
| Hong Kong |
Chan and Lynn, 1989 |
| Mongoloids |
| Sample |
Age |
Number |
Test |
| P R China |
6-16 |
5,108 |
Progressive Matrices |
| Taiwan |
16 |
1,290 |
Culture Fair |
| Singapore |
13 |
147 |
Progressive Matrices |
| Belgium-Koreans |
6-14 |
19 |
WISC |
| United States |
6-17 |
4,994 |
Various |
| United States |
6-11 |
478 |
Various |
| United States |
6-10 |
2,000 |
Figure copying |
| United States |
6 |
80 |
Hunter Aptitude |
| United States |
6-14 |
112 |
Various |
| Koreans |
| Canada-Calgary |
15 |
122 |
Differential aptitude |
| Canada-Vancouver |
6-8 |
38 |
WISC |
| Mongoloids |
Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
| P R China |
101 |
| Taiwan |
105 |
- |
- |
| Singapore |
110 |
- |
- |
| Belgium-Koreans |
110 |
102 |
115 |
| United States |
100 |
97 |
- |
| United States |
101 |
- |
- |
| United States |
105 |
| United States |
106 |
97 |
106 |
| United States |
107 |
| Koreans |
| Canada-Calgary |
105 |
97 |
108 |
| Canada-Vancouver |
100 |
94 |
107 |
|
Mongoloids
|
| Sample |
Source |
| P R China |
Lynn,1991 |
| Taiwan |
Rodd, 1959 |
| Singapore |
Lynn, 1977b |
| Belgium-Koreans |
Frydman and Lynn, 1989 |
| United States |
Coleman et al, 1966; Flynn, 1991 |
| United States |
Jensen and Inouye, 1980 |
| United States |
Jensen, 1973 |
| United States |
Lesser, Fifer and Clark, 1965 |
| United States |
Winick, Meyer and Harris, 1975 |
| Koreans |
| Canada-Calgary |
Vernon, 1982 |
| Canada-Vancouver |
Kline and Lee, 1972 |
Table 3: Mean IQs of various Negroid populations
|
Negroids
|
| Sample |
Age |
Number |
Test |
| Congo |
adults |
320 |
Progressive Matrices |
| Ghana |
adults |
225 |
Culture Fair |
| Nigeria |
6-13 |
87 |
Colored Matrices, PMA |
| Nigeria |
adults |
- |
Progressive Matrices |
| South Africa |
8-16 |
1,220 |
Progressive Matrices |
| South Africa |
adults |
703 |
Progressive Matrices |
| South Africa |
10-14 |
293 |
Army Beta |
| South Africa |
9 |
350 |
Progressive Matrices |
| South Africa |
16 |
1,093 |
Junior Aptitude |
| Uganda |
12 |
50 |
Various |
| Zambia |
adults |
1,011 |
Progressive Matrices |
| Negroids |
Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
Source |
| Congo |
65 |
- |
- |
Ombredane, Robaye and Robaye, 1952 |
| Ghana |
80 |
- |
- |
Buj, 1981 |
| Nigeria |
75 |
- |
81 |
Fahrmeier, 1975 |
| Nigeria |
86 |
- |
- |
Wober, 1969 |
| South Africa |
81 |
- |
- |
Notcutt, 1950 |
| South Africa |
75 |
- |
- |
Notcutt, 1950 |
| South Africa |
65 |
- |
- |
Fick, 1929 |
| South Africa |
67 |
- |
- |
Lynn and Holmshaw, 1991 |
| South Africa |
69 |
60 |
69 |
Owen, 1989 |
| Uganda |
80 |
- |
- |
Vernon, 1969 |
| Zambia |
75 |
- |
- |
Pons, 1974; Crawford Nutt, 1976 |
Table 4: Mean IQs of various Negroid-- Caucasoid hybrid
Populations
| Negroid-Caucasoid Hybrids |
| Sample |
Age |
Number |
Test |
| United States |
- |
- |
362 Studies |
| United States |
4 |
4,550 |
Stanford Binet |
| United States |
2 |
46 |
Stanford Binet |
| United States |
6-18 |
4115 |
Verbal and non-verbal |
| United States |
6 |
111 |
WISC |
| United States |
6-16 |
305 |
WISC-R |
| United States |
7-14 |
642 |
PMA |
| United States |
6-11 |
2,518 |
Various |
| S Africa coloureds |
10-14 |
4,721 |
Army Beta |
| Barbados |
9-15 |
108 |
WISC-R |
| Britain |
11 |
113 |
NFER |
| Britain |
10 |
125 |
British Ability Scales |
| Britain |
8-12 |
205 |
NFER |
| Jamaica |
10-11 |
50 |
various |
| Jamaica |
11 |
50 |
Moray House |
| Jamaica |
5-12 |
71 |
WISC |
| Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
| United States |
85 |
| United States |
87 |
| United States |
86 |
| United States |
84 |
89 |
| United States |
81 |
86 |
80 |
| United States |
84 |
87 |
88 |
| United States |
77 |
77 |
83 |
| United States |
84 |
| S Africa coloureds |
84 |
| Barbados |
82 |
84 |
84 |
| Britain |
86 |
87 |
| Britain |
94 |
92 |
| Britain |
87 |
| Jamaica |
75 |
82 |
90 |
| Jamaica |
72 |
72 |
| Jamaica |
66 |
74 |
64 |
| Sample |
Source |
| United States |
Shuey, 1966 |
| United States |
Broman, Nichols and Kennedy,1975 |
| United States |
Montie and Fagan, 1988 |
| United States |
Coleman et al, 1966 |
| United States |
Miele, 1979 |
| United States |
Jensen and Reynolds, 1982 |
| United States |
Baughman and Dahistrom, 1968 |
| United States |
Jensen and Inouye, 1980 |
| S Africa coloureds |
Fick, 1929 |
| Barbados |
Galler, Ramsey and Forde, 1986 |
|
Britain
|
Mackintosh and Mascie-Taylor, 1985 |
| Britain |
Mackintosh and Mascie-Taylor, 1985 |
| Britain |
Scarr, Caparulo, Bernardo, Tower and Caplan, 1983 |
| Jamaica |
Vernon, 1969
|
| Jamaica |
Manley, 1963; Vernon, 1969 |
| Jamaica |
Hertzig, Birch, Richardson and Tizard, 1972 |
Table 5: Mean IQs of Amerindians Amerindians
| Sample |
Age |
Number |
Test |
| United States |
6-17 |
4,994 |
verbal & non-verbal |
| Navajo |
5-8 |
44 |
WISC |
| Navajo |
4-5 |
27 |
WPPSI |
| Navajo |
6-7 |
26 |
WISC |
| Navajo |
16-17 |
100 |
WAIS |
| Navajo |
- |
44 |
WISC-R |
| Oneidas |
7-14 |
82 |
WISC |
| Canadian Indians |
- |
236 |
WISC-R |
| Ojibwa, Canada |
- |
35 |
WISC-R |
| Ojibwa & Crees, Canada |
6-7 |
33 |
WISC |
| -"- |
9-10 |
31 |
WISC |
| -"- |
14-15 |
36 |
WISC |
| -"- |
16-20 |
60 |
WAIS |
| Dakota Indians |
6-16 |
200 |
WISC-R |
| Papago |
6-16 |
240 |
WISC-R |
| Amerindians |
Intelligence |
| Sample |
General |
Verbal |
Visuo-spatial |
| United States |
94 |
89 |
| Navajo |
79 |
65 |
93 |
| Navajo |
75 |
64 |
91 |
| Navajo |
78 |
66 |
96 |
| Navajo |
89 |
84 |
95 |
| Navajo |
78 |
84 |
95 |
| Oneidas |
91 |
86 |
97 |
| Canadian Indians |
97 |
90 |
105 |
| Ojibwa, Canada |
97 |
91 |
104 |
| Ojibwa & Crees, Canada |
86 |
70 |
101 |
| -"- |
90 |
81 |
100 |
| -"- |
89 |
78 |
101 |
| -"- |
87 |
91 |
103 |
| Dakota Indians |
95 |
86 |
102 |
| Papago |
86 |
75 |
96 |
|
Amerindians
|
Source |
| Sample |
| United States |
Coleman et al, 1966 |
| Navajo |
Thurber, 1976 |
| Navajo |
Cundick, 1970 |
| Navajo |
Cundick, 1970 |
| Navajo |
Howell, Evans & Downing, 1958 |
| Navajo |
Teeter, Moore & Peterson, 1982 |
| Oneidas |
Turner & Penford, 1952 |
| Canadian Indians |
Crawley in McShane & Plas, 1984 |
| Ojibwa, Canada |
McShane & Plas, 1984 |
| Ojibwa & Crees, Canada |
St John, Krichev & Bauman, 1976 |
| -"- |
-"- |
| -"- |
-"- |
| -"- |
-"- |
| Dakota Indians |
Browne, 1984 |
| Papago |
Reschly & Jipson, 1976 |
Table 6: Mean IQs of various south East Asian populations
|
South East Asians
|
| Sample |
Age |
Number |
Test |
| Australia |
- |
- |
Peabody Picture |
| Aborigines |
5-13 |
83 |
Vocabulary |
| Australia |
- |
- |
Peabody Picture |
| Aborigines |
3-4 |
22 |
Vocabulary |
| Australia |
- |
- |
| Aborigines |
9 |
1,000 |
Queensland |
| New Zealand |
- |
- |
Primary Mental |
| Maoris |
13 |
151 |
Abilities |
| New Zealand |
- |
- |
Progressive |
| Maoris |
8-14 |
303 |
Queensland |
| New Zealand |
- |
- |
Progressive |
| Polynesians |
8-9 |
71 |
Achievement |
|
Carolines
|
| Micronesians |
12-18 |
400 |
Culture Fair |
| Singapore |
| Malays |
14 |
190 |
Progressive Matrices |
|
Intelligence
|
| Sample |
General |
Verbal |
Visuo-spatial |
| Australia |
| Aborigines |
- |
80 |
| Australia |
| Aborigines |
- |
67 |
| Australia |
| Aborigines |
85 |
| New Zealand |
| Maoris |
92 |
95 |
87 |
| New Zealand |
| Maoris |
90 |
| New Zealand |
| Polynesians |
- |
87 |
|
Carolines
|
| Micronesians |
88 |
| Singapore |
| Malays |
96 |
| Sample |
Source |
| Australia Aborigines |
Bruce, Hengeveld & Radford, 1971 |
| Australia Aborigines |
Nurcombe and Moffit, 1970 |
| Australia Aborigines |
McElwain and Kearney, 1973 |
|
New Zealand Maoris
|
Walters, 1958 |
|
New Zealand Maoris
|
Harker, 1978 |
|
New Zealand Maoris
|
St George, 1983 |
|
New Zealand Polynesians
|
Beck and St George, 1983 |
|
Carolines Micronesians
|
Jordheim and Olsen, 1963 |
|
Singapore Malays
|
Lynn, 1977b |
Table 7 Means for Progressive Matrices and 12 reaction time
measures for 9 year old children from five countries (in
milliseconds).
| - |
Hong Kong |
Japan |
Britain |
| Number |
118 |
444 |
239 |
| Progressive Matrices IQ |
113 |
110 |
100 |
|
Decision time
|
| simple |
361 |
348 |
371 |
| complex |
423 |
433 |
480 |
| omo |
787 |
818 |
898 |
|
Movement time
|
| simple |
273 |
218 |
236 |
| complex |
267 |
227 |
261 |
| omo |
323 |
268 |
297 |
|
Decision time variabilities
|
| simple |
99 |
103 |
90 |
| complex |
114 |
138 |
110 |
| omo |
269 |
298 |
285 |
| Movement time variabilities |
| simple |
68 |
63 |
52 |
| complex |
65 |
66 |
56 |
| omo |
136 |
127 |
110 |
| - |
Ireland |
South Africa |
SD |
r |
|
Number Progressive Matrices IQ
|
317 |
350 |
| Decision time |
89 |
67 |
| simple |
388 |
400 |
64 |
-94 (**) |
| complex |
485 |
501 |
67 |
-89 (*) |
| omo |
902 |
991 |
187 |
-96 (**) |
|
Movement time
|
| simple |
260 |
236 |
72 |
13 |
| complex |
280 |
236 |
66 |
13 |
| omo |
307 |
256 |
96 |
56 |
| Decision time variabilities |
| simple |
121 |
129 |
32 |
-83 (*) |
| complex |
141 |
155 |
30 |
-73 |
| omo |
328 |
332 |
95 |
-85 (*) |
| Movement time variabilities |
| simple |
73 |
69 |
30 |
-33 |
| complex |
80 |
70 |
25 |
-42 |
| omo |
129 |
119 |
49 |
40 |
One and two asterisks denote
statistical significance at the 5 and 1 per cent level,
respectively.
REFERENCES
Asimov, I. 1989; Chronology of Science and Discovery.
London: Grafton Books.
Baker, J.R. 1974; Race. Oxford:
Oxford University Press.
Baughman, E.E. and Dahlstrom, W.G. 1988; Negro and White
Children. New York, Academic Press.
Beck, L.R. and St. George, R. 1983; The alleged cultural
bias of the PAT: Reading Comprehension and Reading Vocabulary
Tests. New Zealand Journal of Educational
Studies, 18, 32-47.
Berte, R. 1961; Essai d'adaptation de l'echelle
d'intelligence pour enfants de D. Wechsler a des ecoliers beiges
d'expression francaise, Brussels, Centre Nationale de
Researches de Psychotechnique Scolaire.
Borjas, G. J. 1986; The self-employment experience of
immigrants. Journal of Human Resources. 21,
485-506.
Bourdier, G. 1964; Utilisation et nouvel etallonage du P.M.
47 Bulletin de Psychologie, 235, 39-41.
Bowman, M.L. 1989; Testing individual differences in ancient
China. American Psychologist. 44, 576-578.
Brandt, I. 1978; Growth dynamics of low birth weight infants
with emphasis on the perinatal period. In: Human
Growth vol. 2 ed. F. Falkner and J.M. Tanner, pp. 557-617. New
York: Plenum Press.
Broman, S.H., Nichols, P.L. and Kennedy W. A 1975; Preschool
IQ. New York: J. Wiley.
Broman, S, Nichols, P.L. Shaughnessy, P. and Kennedy W. 1987;
Retardation in Young Children. Hillsdale, New Jersey:
Lawrence Erlbaum.
Bruce, D.W., Hengeveld, M. and Radford, W.C. 1971; Some
cognitive skills in Aboriginal children in Victorian primary
schools. Victoria, Australian Council for Educational
Research.
Burt, C. 1949; The structure of the mind: a review of the
results of factor analysis. British Journal of Educational
Psychology. 19, 110-111.
Buj, V. 1981; Average IQ values in various European
countries. Personality' and Individual Differences,
2, 168-169.
Cattell, R. B. 1971; Abilities. Boston: Houghton
Mifflin.
Centre de Psychologie Applique 1957; Manual of the Wechsler
Intelligence Scale for child rent. Paris, Centre de
Psychologie Applique
Coleman, J.S. 1990; Personal communication
Coleman, J.S. et al 1966; Equality of Educational
Opportunity Washington, D. C., U. S. Office of Education.
Cundick, B.P. 1970; Measures of intelligence of southwest
Indian students. Journal of Social Psychology 81,
151-156.
Du Chateau, P. 1967; Ten point gap in Maori aptitudes.
National Education. 49, 157-158.
Eysenck, H.J. 1971; Race, intelligence and education.
London: London: Smith.
Eysenck, H.J. 1982; A Model for Intelligence. Bolin:
Springer-Verlag.
Fahrmeier, E.D. 1975; The effect of school attendance on
intellectual development in Northern Nigeria. Child
Development, 46, 281-285.
Fick, M.L. 1929; Intelligence test results of poor white,
native (Zulu), colored and Indian school children and the
educational and social implications. South African Journal
of Science. 26, 904-<320.
Firkowska, A., Ostrowska, A., Sokolowska, M., Stein, Z., Susser,
M. and Wald, 1978; Cognitive development and social
policy. Science. 200, 1357-13G2.
Fitzgerald, J.A. and Ludemall, W.W. 1926; The intelligence
of Indian children. Journal of Comparative
Psychology, 6, 319-328.
Flynn, J.R. 1980; Race IQ and Jensen. London: Routledge
and Kegan Paul.
- 1987; Massive IQ gains in l4 nations: what IQ tests really
measure. Psychological Bulletin. 101,
271-293.
- 1989; Rushton, evolution and race: an essay on intelligence
and virtue. The Psychologist, 2,
363-366.
Frydman, M. and Lynn, R. 1989; The intelligence of Korean
children adopted in Belgium. Personality and individual
Differences, 10, 1323-1326.
Galler, J.R., Ramsey, F. and Forde, V. 1986; A follow up
study in the influence of early malnutrition 011 subsequent
development. Nutrition and Behavior. 3, 211-222.
Galton, F. 1869; Hereditary Genius. London:
Macmillan.
Goodenough, F.L. 1926; Racial differences in the
intelligence of school children. Journal of Experimental
Psychology. 9, 388-397.
Goosens, G. 1952; Une application du test d'intelligence de
R.B. Cattell. Revue Belge de Psychologie et de
Pedagogie. 19, 115-124.
Gould, S.J. 1981; The Mismeasure of Man. New York,
Norton.
Harker, R.K. 1978; Achievement and ethnicity: environmental
deprivation or cultural difference. New Zealand
Journal of Educational Studies, 13, 107-124.
Hertzig, M.E., Birch, H.G., Richardson, S.A. and Tizard, J.
1972; Intellectual levels of school children severely
malnourished during the first two years of life.
Pediatrics, 49, 814-824.
Hodgkiss, J. 1979; British Manual for the Differential
Attitude Tests Windsor. Windsor.National Foundation for
Educational Research.
Ho, H-Z, Baker, L.A. and Decker, S.N. 1988; Covariation
between intelligence and speed of cognitive processing: genetic and
environmental influences. Behavior Genetics. 18,
247-261.
Howell, R.J., Evans, L. and Downing, L.N. 1958; A comparison
of test scores from the 16-17 year age group of Navajo Indians with
standardization norms from the WAIS. Journal of Social
Psychology. 47, 355-359.
Jaynes, G.D. and Williams, R.M. 1989; A Common Destiny:
Blacks and American Society. Washington DC. National Research
Council.
Jensen, A.R. 1972; Genetics and Education. London.
Methuen.
- 1973; Educability and Group Differences. London.
Methuen.
- 1982; Reaction time and psychometric. In H.J. Eysenck
(ed). A Model for Intelligence. Berlin:
Springer-Verlag.
Jensen, A. R. and Inouye, A.R. 1980; Level 1 and Level II
abilities in Asian, white and black children.
Intelligence. 4, 41-49.
Jensen, A.R. and Reynolds, C.R. 1982; Race, social class and
ability patterns on the WISC-R. Personality!and Individual
Differences, 3, 423-438.
Jordheim, G.D. and Olsen, I.A. 1963; The use of a non-verbal
test of intelligence in the trust territory of the Pacific.
American Anthropologist, 65, 1122-1125.
Kline, C.L. and Lee, N. 1972; A transcultural study of
dyslexia: analysis of language disabilities in 277 Chinese children
simultaneously learning to read and write in English and in
Chinese. Journal of Social Education, 6, 9-26.
Kurth, von E. 1969; Erhobung der Leistungsnormen bei den
farbigen progressiven matrizen. Zeitschrift fur
Psychologie 177, 85-90.
Lesser, G.S., Fifer, F. and Clark, H. 1965; Mental abilities
of children from different social class and cultural groups.
Monographs of the Society for Research in Child
Development. 30.
Linn, M C. and Petersen, A.C. 1986; A mete analysis of
gender differences in spatial ability: implications for mathematics
and science achievement. In J.S. Hyde and M.C. Linn (eds)
The Psychology of Gender. Baltimore: Johns Hopkins
University Press.
Lynn,R. 1977a; The intelligence of the Japanese.
Bulletin of the British Psychological Society,30
69-72.
- 1977b; The intelligence of the Chinese and Malays in
Singapore. The Mankind Quarterly. 18,
125-128.
- 1987; The intelligence of the Mongoloids: a psychometric,
evolutionary and neurological theory. Personality
and Individual Differences. 8,813 -844.
- 1990; The role of nutrition in secular increases in
intelligence. Personality and Individual
Differences. 11, 273-285.1991; Intelligence in China.
Social Behavior and Personality, to appear.
Lynn, R., Chan, J. and Eysenck, H.J. 1991; Reaction times
and intelligence in Chinese and British children.
Perceptual and Motor Skills.
Lynn, R. and Hampson, S. 1986a; Intellectual abilities of
Japanese children: an assessment of 2 1/2-8 1/2 year olds derived
from the McCarthy Scales of Children's Abilities.
Intelligence. 10, 41-58.
Lynn, R. and Hampson, S. 1986b; Further evidence 011 the
cognitive abilities of the Japanese: data from the WPPSI.
International of Behavioral Development 10,23-36.
- 1986c; The structure of Japanese abilities: an analysis in
terms of the hierarchical
model of intelligence. Current Psychological
Research and Reviews, 4, 309-322.
- 1986d; The rise of national intelligence: evidence from
Britain, Japan and the United States. Personality
and Individual Differences, 7, 23 -32.
Lynn, R., Hampson, S. and Bingham,] R. 1987; Japanese,
British and American adolescents compared for Spearman's g and for
the verbal, numerical and visio-spatial abilities.
Psychologia. 30, 137-144.
Lynn, R., Hampson, S.L. and Iwawaki, S. 1987; Abstract
reasoning and spatial abilities among American, British and
Japanese adolescents. The Mankind Quarterly. 27,
397-434.
Lynn, R. and Holmshaw, M. 1991; Black-white Differences in
reaction times and intelligence. Social Behavior and
Personality. (to appear)
Lynn, R., Pagliari, C. and Chan, J. 1988; Intelligence in
Hong Kong measured for Spearman's g and the visuospatial and verbal
primaries. Intelligence. 12, 423-433.
Lynn, R. and Shigehisa, T. 1991; Reaction times and
intelligence in British and Japanese children. Journal of
Biosocial Science. (to appear)
McIntyre, G. A. 1938; The Standardization of Intelligence
Tests in Australia. Melbourne, University Press.
Mackintosh, N.J. and Mascie-Taylor, C.G.N. 1985; The IQ
question. In Education For All (The Swann
Report) Cmnd paper 4453. London: HMSO.
McShane, D.A. and Plas, J.M. 1984; The cognitive functioning
of American Indian children: moving from the WISC to the
WISC-R. School Psychology Review. 17,39-51.
Manley, D.R. 1963; Mental ability in Jamaica.
Social and Economic Studies, 12, 51-77.
Maqsud, M. 1980; Extraversion, neuroticism, intelligence and
academic achievement in Northern Nigeria. British Journal
of Educational Psychology. 50., 71 -73.
Mercer, J.R. 1984; What is a racially and culturally
discriminating test? In C.R. Reynolds and R.T. Brown (eds)
Perspectives on bias in mental testing. New York,
Plenum.
Miele, F. 1979; Cultural bias in the WISC.
Intelligence, 3, 149-164.
Montie, J.E. and Fagan, J.F. 1988; Racial differences in IQ:
item analysis of the Stanford-Binet at 3 years.
Intelligence, 12, 315-332.
Murdock, J. and Sullivan, L.R. 1923; A contribution to the
study of mental and physical measurements in normal school
children. American Physical Education Review, 28,
209-330.
Naglieri, J. and Jensen, A.R. 1987; Comparison of
black-white differences on the WISCR and the K-ABC: Spearman's
hypothesis. Intelligence . 11, 21 -43.
Nagoshi, C.T. and Johnson, R.C. 1987; Cognitive abilities
profiles of Caucasian vs Japanese subjects in the Hawaii family
study of cognition. Personality' and Individual
Differences 8, 581-583.
Needham, J. 1954; Science and Civilisation in China.
Cambridge: Cambridge University Press.
Nieto-Alegre, S., Navarro, L., Santa Cruz, G. and Dominguez, A.
1987; Diferencices regionales en la medida de la inteligencia
con el test M.P. Revista de Psicologia General y
Aplicado, 22, 699-707.
Notcutt, B. 1950; The measurement of Zulu intelligence.
Journal of Social Research. 1,195-206.
Nurcombe, B. and Moffit, P. 1970; Cultural deprivation and
language deficit. Australian' Psychologist, 5,
249-259.
Ombredane, A., Robaye, F. and Robaye, E. 1952; Analyse des
resultats d'une application experimentale du matrix 38 a 485 noirs
Baluba. Bulletin contre d'etudes et reserches
psychotechniques 7, 235-255.
Owen, K. 1989; Test and item bias: the suitability of the
Junior Aptitude Test as a common test battery for white, Indian and
black pupils in Standard 7. Pretoria: Human Sciences Research
Council.
Pons, A. L. 1974; Administration of tests outside the
cultures of their origin. 26th Congress South African
Psychological Association.
Radcliffe, J.A. and Turner, F.E. 1969; Manual for the
Australian version of the WISC. Hawthorn, Victoria: Australian
Council for Educational Research.
Raven, J. 1981; Manual for Raven's Progressive Matrices and
Mill Hill Vocabulary Scales. London. H.K. Lewis.
Raven, J 1986; Manual for Raven's Progressive Matrices and
Vocabulary Scales. Research Supplement 3. London,
H.K. Lewis.
Raven, J. and Court, J.H. 1989; Manual for Raven's
Progressive Matrices and Vocabulary. Scales-Research
Supplement No 4. London, H.K. Lewis.
Reddington, M.J., and Jackson, K. 1981; Raven's colored
progressive matrices: a Queensland standardisation.
ACER Bulletin. 30, 20-28.
Redmond, M. and Davies, F.R.J. 1940; The standardisation of
Two Intelligence Tests. Wellington, New Zealand Council for
Educational Research.
Reed, T. E. 1969; Caucasian genes in American Negroes.
Science. 165, 762-8.
Reschly, D.J. and Jipson, F.J. 1976; Ethnicity, geographical
locale, age, sex and urbanrural residence as variables in the
prevalence of mild retardation. American Journal of Mental
Deficiency, 81, 151-161.
Reuning, H. 1988; Testing Bushmen in the Central
Kalahari. In S.H. Irvine and J.W.
Berry (eds) Human Abilities in Cultural Context.
Cambridge, Cambridge University Press.
Reynolds, C.R. and Jensen, A.R. 1983; WISC-R subscale
patterns of abilities of blacks and whites matched on full scale
IQ. Journal of Educational Psychology. 75,
75,207-214.
Rodd, W.G. 1959; A cross cultural study of Taiwan's
Schools. Journal of Social Psychology. 50, 3-36.
St. George, R. 1983; Some psychometric properties of the
Queensland Test of Cognitive Abilities with New Zealand, European
and Maori children. New Zealand Journal of
Psychology. 12, 57-68.
St. John, J. Krichev, A. and Bauman, E. 1976; North Western
Ontario Indian children and the WISC. Psychology in the
Schools. 13, 407-411.
Scarr, S., Caparulo, B.K. Ferdman, B.M., Tower, R.B. and Caplan,
J. 1983; Developmental status and school achievements of
minority and non-minority children from birth to 18 years in a
British Midlands town. British Journal of Developmental
Psychology. I, 31-48.
Scarr, S. and McCartney, K. 1983; How people make their own
environments: a theory of genotype-environment effects.
Child Development 54, 424-435.
Schmidtke, A., Schaller, S. and Becker, P. 1978;
Raven-Matrizen Test Manual Deutsche Bearbeitung. Weinheim
Beltz Test Gesellschaft, Berlin.
Schreider, E. 1968: Quelques correlations somatiques des
tests mentaux. Homo. 19, 38-43.
Scottish Council for Research in Education 1933; The
Intelligence of Scottish Children. London: London University
Press.
- 1939; The Intelligence of a Representative Group of
Scottish children. London
University of London Press.
- 1949; The Trend of Scottish Intelligence. London:
University of London Press.
Shigehisa, T. and Lynn, R. 1991; Reaction times and
intelligence in Japanese children. International Journal
of Psychology, 00, 000-000.
Shuey, A.M. 1966; The Testing of Negro Intelligence.
New York, Social Science Press.
Sinha, U. 1968; The use of Raven's Progressive Matrices in
India. Indian Educational Review, 3, 75-88.
Skandinaviska Testforlaget 1970; Manual of the Swedish
IVISC. Stockholm: Skandinaviska Testforlaget.
Snyderman, M. and Rothman, S. 1988; The IQ Controversy, the
Media and Public Policy. New Brunswick, Transection Books.
Spearman, C. 1927; The abilities of man. New York:
Macmillan.
Stevenson, H.W., Stigler, J.W., Lee, S., Lucker, CAY., Kitanawa,
S. and Hsu, C. 1985; Cognitive performance and academic
achievement of Japanese, Chinese and American children.
Child Development. 56, 718-734.
Susanne, C. and Sporoq, J. 1973; Etude de correlations
existent entre des tests psychotechniques et des mensurations
cephaliques. Bulletin Societe Royal Belge Anthropologie et
Prehistorie, 84, 59-63.
Teeter, A., Moore, C. and Petersen, J. 1982; WISC-R verbal
and performance abilities of Native American students referred for
school learning problems. Psychology in the schools.
1 9, 39-44.
Tesi, G. and Young, H.B. 1962; A standardisation of Raven's
Progressive Matrices 1938. Archivio.
Thurber, S. 1976; Changes in Navajo responses to the
draw-a-man test. Journal of Social Psychology 99, 139-110.
Thurstone, L. L. 1983; Primary Mental Abilities.
Chicago, Chicago University Press.
Turner, G.H. and Penfold, D.J.1952 ;The scholastic aptitude
the Indian children of the Caradoc reserve. Canadian Journal of
Psychology. 6, 31-41.
United Nations 1970; National Accounts Statistics. New
York, United Nations.
Vejleskov, H. 1968; An analysis of Raven Matrix responses in
fifth grade children.Scandinavian Journal of Psychology 9,
177-186.
Vernon, P.A., 1989; The heritability of measures of speed of
information-processing.Personality and Individual Differences.
10, 573-576.
Vernon, P.E. 1969; Intelligence and Cultural
Environment. London, Methuen.
Vernon, P.E 1982; The Abilities and Achievements of
Orientals in North America. New York: Academic Press.
Wainer, H. 1988; How accurately can we assess changes in
minority performance on the SAT? American Psychologist, 43,
774-778.
Weinberg, W.A., Dietz, S.G., Penick, .. and McAlister, W.H.
1974; Intelligence, reading achievement, physical size and
social class. Journal of Pediatrics, 85, 482-489.
Weyl,N. 1969; Some comparative performance indexes of
American ethnic minorities. The Mankind Quarterly. 9, 106-
128.
Weyl,N 1989; The Geography of American Achievement.
Washington, D.C.: Scott-Townsend.
Winick, M., Meyer, K.K. and Harris, R.C.1975; Malnutrition
and environmental enrichment by early adoption. Science. 190,
1173-1175.
Wober, M. 1969; The meaning and stability of Raven's
Matrices Test among Africans. International Journal of
Psychology, 4, 229-235.
Zahirnic, C., Girboveanu, M., Onofrei, A., Turcu, A., Viocu, G.,
Voicu, G., M.,and Visan, O.M. 1974; Etalonarea matriceolur
progressive colorate Raven pe copii de 6-10 ani in
Municipal Bucuresti. Revue Psihologi,. 20, 313-321.
About the author
Richard Lynn is professor
emeritus at the University of Ulster, Coleraine, Northern
Ireland.
Source
The Mankind
Quarterly, Vol. 31, No. 3 (Spring 1991), pp. 255-296.