Intelligence Testing March 8, 2006 Pauline Yu and Neha Begwani March 8, 2006 Pauline Yu and Neha Begwani

History R“I advance it, therefore, as a suspicion only, that the blacks, whether originally a distinct race, or made distinct by time and circumstance, are interior to the whites in he endowment both of body and of mind.” Thomas Jefferson

Craniometry RGeorge Morton RHypothesis: “objectively by physical characteristics of the brain, particularly by its size.” RApproximate intelligence by measuring the volume of the cranium RLarge sources of bias in methodology RGeorge Morton RHypothesis: “objectively by physical characteristics of the brain, particularly by its size.” RApproximate intelligence by measuring the volume of the cranium RLarge sources of bias in methodology

Morton’s Results RaceNumber of Observations MeanLargestSmallest Caucasian Asian Polynesian Native American African

Brain Size as Proxy for Intelligence RCorrelation between body size and cranium size R“This fact does not imply that big people are smarter—any more than elephants should be judged more intelligent than humans because their brains are larger.” (Gould, 61) RCorrelation between body size and cranium size R“This fact does not imply that big people are smarter—any more than elephants should be judged more intelligent than humans because their brains are larger.” (Gould, 61)

Bias in Sample Size RMorton’s experimentation suffered from disproportionate sample size RUnequal representation of subgroups within a race group RNative American sample R25% was the smaller brained Inca Peruvians R2% was the larger brained Iroquois RMorton’s experimentation suffered from disproportionate sample size RUnequal representation of subgroups within a race group RNative American sample R25% was the smaller brained Inca Peruvians R2% was the larger brained Iroquois

Morton’s Subconscious RBias from subconscious belief in superiority of white race RPacking the craniums of white subjects as tightly as possible RDid not put same effort for Black and Native American Races RRounded results to further skew data RBias from subconscious belief in superiority of white race RPacking the craniums of white subjects as tightly as possible RDid not put same effort for Black and Native American Races RRounded results to further skew data

Racial Comparisons Paul Broca ( ) compared the radius:humerus ratios in humans (larger ratio = longer forearm) Apes have long forearms Paul Broca ( ) compared the radius:humerus ratios in humans (larger ratio = longer forearm) Apes have long forearms

Ratios RWhites RBlacks But….. REskimos RNative Americans RWhites RBlacks But….. REskimos RNative Americans Broca concluded: “After this, it seems difficult to say that elongation of the forearm is a character of degradation or inferiority”

Stanford-Binet Test Sample Questions (1911 Version): An Indian who had come to town for the 1st time in his life saw a white man riding across the street. As the white man rode by, the Indian said - “The white man is lazy; he walks sitting down.” What was the white man riding on that caused the Indian to say, “He walks sitting down.” My neighbor has been having queer visitors. First a doctor came into the house, then a lawyer, then a minister. What do you think happened there? Sample Questions (1911 Version): An Indian who had come to town for the 1st time in his life saw a white man riding across the street. As the white man rode by, the Indian said - “The white man is lazy; he walks sitting down.” What was the white man riding on that caused the Indian to say, “He walks sitting down.” My neighbor has been having queer visitors. First a doctor came into the house, then a lawyer, then a minister. What do you think happened there?

Catherine Cox RAttempted to estimate the IQs of 282 geniuses RFlawed and illogical but… from this study she earned a PhD from Stanford! RAttempted to estimate the IQs of 282 geniuses RFlawed and illogical but… from this study she earned a PhD from Stanford! Some of her results: Average A1 IQ (birth-17) Average A2 IQ (17-24) Major flaw - IQ is not supposed to alter with age. “Normal” IQ Range:

Yerkes and the Army Exams “Examinations Alpha and Beta are so constructed and administered as to minimize the handicap of men who because of foreign birth or lack of education are little skilled in the use of English. These group examinations were originally intended and are now definitely known to measure native intellectual ability.” - Yerkes

Army Examination (Alpha) RThe most prominent industry in Detroit is (A) automobiles (B) brewing (C) flour (D) packing RVelvet Joe appears in advertisements for (A) tooth powder (B) dry goods (C) tobacco (D) soap RThe most prominent industry in Detroit is (A) automobiles (B) brewing (C) flour (D) packing RVelvet Joe appears in advertisements for (A) tooth powder (B) dry goods (C) tobacco (D) soap Results: Average mental age of white American adults stood at 13! European immigrants: Russian , Italian , Pole IQ = (Mental Age / Actual Age) X 100

IQ Testing Today RMajor Cultural Biases in Testing: RNon-verbal Raven’s test vs. highly verbal Peabody Picture test RBITCH test developed to counter the cultural differences RMajor Cultural Biases in Testing: RNon-verbal Raven’s test vs. highly verbal Peabody Picture test RBITCH test developed to counter the cultural differences