Educability-and-Group-Differences-1973-by-Arthur-Robert-Jensen

Culture-biased Tests 317
therefore seem reasonable to attribute the significant differences
between the part- and the full-Aborigines in this study to genetic
differences between Aborigines and Europeans, resulting in the
part-Aboriginal children having a higher probability of inheriting
a higher intellectual potential, (p. 268)
Finally, what do the Piagetian tests reveal about the cognitive
development of American Negro children Read Tuddenham
(1970) carried out the major study, giving a battery of ten Piagetian
tests to some 500 white, Negro, and Oriental children in grades 1
to 3 in three California communities. Negroes did less well than
whites on every item. The average percentage of children possessing
the concept tested by the particular items was 32-6 for whites
v. 15-9 for Negroes. Oriental children, on the other hand, were
more advanced than white children on seven of the ten items.
The Piagetian scale also correlates substantially with SES as indexed
by father’s occupation, even though, as Tuddenham notes,
‘these items tend to involve reasoning about matters universally
available to observation, e.g., the horizontality of water levels.
It is hard to see how social advantage could be a very large factor
in success on some of these items. The genetic selection implicit
in occupational level may well have more to do with it’ (p. 65).6
Gaudia (1972) administered a series of Piagetian conservation
tasks to 126 low SES American Indian, Negro, and white children
in grades 1 to 3. Overall, these groups, all being of very low SES,
averaged about one year behind the age norms on these tests based
on samples of the general population. But the Negro children in
this study were significantly (p < 0*001) delayed in the acquisition
of conservation (of area, number, quantity, weight, and mass) as
compared with the low SES Indians and whites, who did not
differ significantly. The racial disparity was greatest in the older
age groups. Expressed as a percentage of the highest possible
conservation score, the means of the three age-matched ethnic
groups are: white = 51, Indian = 51, Negro = 30.
How much does specific training in attention and classification
raise children’s performance in these Piagetian tests To find out,
Sigel and Olmsted (1970) gave one month of training on certain
skills and concepts intended to promote cognitive development
to Negro children enrolled in a Head Start program. A year after
the training, these children were compared with a matched control