Gould - Measuring differences

• How was psychology perceived in the 1900s and how did Yerkes want to change this?

  • Psychology was not perceived as a proper science because it lacked objectivity
  • Yerkes wanted to use consistent and reliable measures
• What did Yerkes believe about intelligence?

  • It is inherited
• What did Gould aim to do in his review?

  • Identify problems with psychometric testing and measuring intelligence in history using Yerkes as an example
  • Identify problems of theoretical bias influencing research
  • Identify problems of political and ethical implications
• Who was the sample in Yerkes study?

  • 1.75 million army recruits in the USA - White Americans, European immigrants, Black Americans
• What was the alpha test and it’s purpose?

  • 8 parts
  • Included analogies, fill in next number in sequence, unscrambling sentences etc
  • Given to literate recruits
  • Culturally specific to America
• What was the beta test and it’s purpose?

  • 7 parts
  • Given to illiterate recruits and men who had failed alpha
  • Consisted of pictoral tasks such as maze tests, counting cubes, and next series in symbols
  • 3 parts answers were given in writing
  • Culturally specific to America
• What was the individual spoken exam and it’s purpose?

  • For men who failed beta
  • Graded from A to E and labelled whether they were suitable for a position in the army
  • Was rarely done so it lacked consistency
• What were the findings of the Yerkes study?

  • The average age of White Americans was 13 when the standard was 16 - claimed to be caused by interbreeding with Black Americans lowering overall intelligence
  • Darker people of southern Europe and Slavs of Eastern Europe were graded as less intelligent than the fair people of western and northern Europe
  • Black men were at the bottom of the scale with an average mental age of 10.41, however the lighter they were the higher the score
• What were the implications of the Yerkes study?

  • Adapted Immigration Act as a result and people from southern / eastern Europe were “not welcome” in America
  • Data was used to promote racism and discrimination in books (Bringham)
• What can be concluded from Yerkes study?

  • Nations can be graded by intelligence
  • IQ tests are culturally and historically biased
  • IQ tests do not measure innate intelligence
  • Unreliable as lacks consistency
  • Doesn‘t produce valid results
  • Leads to tragic consequences as influenced social policies
  • America is a nation of morons
• What is the background?

  • in 1904, the Simon – Binet test, the worlds first intelligence test was developed. Five years later this was adapted for use in the USA and it became known as the Stanford – Binet test.
  • In 1944 the most widely used test of adult intelligence, the Wechsler Adult Intelligence Scale (WAIS) was introduced
  • When America became involved in WW1 , Over 1 million recruits where required. So colonel Yerkes combined his early ideas of inherited intelligence and development of mental testing and developed the Army Alpha and Beta tests