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 earthquake. Many predictions have been made since then, by various scientists, based on diverse techniques. Still we lack reliable techniques for earthquake prediction. Said Lucy Jones [1990] of the U.S. Geological Survey, “When people want something too much, it’s very easy to overestimate what you’ve got.” Most of the altruistic predictions suffered from one of the following pitfalls:

wish-fulfilling assumption or treatment of a variable; biased sampling; or confirmation bias in data interpretation.

The following examples were used by Gould [1981] to illustrate the severe societal damage that lapses in scientific objectivity can inflict. If an objective, quantitative measure of intelligence quotient (IQ), independent of environment, could be found, then education and training possibly could be optimized by tailoring them to this innate ability. This rationale was responsible for development of the Army Mental Tests, which were used on World War I draftees. Among the results of these tests were the observations that white immigrants scored lower than white native-born subjects, and immigrant scores showed a strong correlation with the number of years since immigration. The obvious explanation for these observations is that the tests retained some cultural and language biases. The actual interpretation, which was controlled by desire for the tests to be objective measures of IQ, was the following: a combination of lower intelligence in Europeans than in Americans and of declining intelligence of immigrants. This faulty reasoning was used in establishing the 1924 Immigration Restriction Act. [Gould, 1981]

Pitfalls: wish-fulfilling assumption or treatment of variable; ignoring relevant variables; hidden control of prior theories on conclusions.

Bean ‘proved’ black inferiority by measuring brain volumes of blacks and whites and demonstrating statistically that black brains are smaller than white brains. His mentor Mall replicated the experiment, however, and found no significant difference in average brain size. The discrepancy of results is attributable to Mall’s use of a blind: at the time of measurement, he had no clues as to whether the brain he was measuring came from a black or white person. Bean’s many measurements had simply reflected his expectations. [Gould, 1981]

Pitfalls: biased evaluation of subjective data; advocacy masquerading as objectivity.

In order to demonstrate that blacks are more closely related to apes than whites are, Paul Broca examined a wide variety of anatomical characteristics, found those showing the desired correlation, and then made a large number of careful and reliable measurements of only those characteristics. [Gould, 1981]

Pitfalls: confirmation bias in experimental design (selecting the experiment most likely to support one’s beliefs); confirmation bias in data interpretation; hidden control or prior theories on conclusions; advocacy masquerading as objectivity.