Cumulative Deficit in IQ of Blacks in the Rural South
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Cumulative Deficit in IQ of Blacks in the Rural South ARTHUR R. JENSEN (1977) University of California, Berkeley The cumulative deficit hypothesis with respect to age decrement in IQ between the ages of 5 and 18 was investigated in large samples of white and black school children in rural Georgia. Age decrement in verbal and nonverbal IQ was measured by the average IQ difference between younger and older siblings. It was found that blacks (but not whites) showed significant and substantial decrements in both verbal and nonverbal IQs as a linear function of age in the rank from about 5 to 16 years of age. An environmental interpretation of the age decrement in IQ seems reasonable in view of the comparative lack of such a decrement in a parallel study of California blacks whose environmental circumstances are markedly better than those of the black sample from rural Georgia.
Cumulative Deficit in IQ of Blacks in the Rural South
Cumulative Deficit in IQ of Blacks in the…
Cumulative Deficit in IQ of Blacks in the Rural South
Cumulative Deficit in IQ of Blacks in the Rural South ARTHUR R. JENSEN (1977) University of California, Berkeley The cumulative deficit hypothesis with respect to age decrement in IQ between the ages of 5 and 18 was investigated in large samples of white and black school children in rural Georgia. Age decrement in verbal and nonverbal IQ was measured by the average IQ difference between younger and older siblings. It was found that blacks (but not whites) showed significant and substantial decrements in both verbal and nonverbal IQs as a linear function of age in the rank from about 5 to 16 years of age. An environmental interpretation of the age decrement in IQ seems reasonable in view of the comparative lack of such a decrement in a parallel study of California blacks whose environmental circumstances are markedly better than those of the black sample from rural Georgia.