Chapter 2

Historical Considerations

• Psychometrics: measurement of psychology• Anthropometry : measurement of human• Before 20 century scientists believe that the skull

size and intelligence have a positive association. Bigger head more intelligent.

• "Determinists arguments for ranking people according to a single scale of intelligence, no matter how numerically sophisticated, have recorded little more than social prejudice." (Gould, 1981, pp. 27-28) Gould’s book is controversial because some people said that he mis-cited certain studies.

Alfred Binet • The purpose of IQ tests is to identify the children who need help and special education, not to classify normal people.

• He declined to define IQ as fixed, inborn intelligence.

• He refused to accept IQ as an absolute measure; intelligence is too complex to be captured by a single number. The scale is a rough guide only.

Henry H. Goddard • Invented the term “moron”: a person with a mental age in adulthood of between 8 and 12 (IQ of 51-70) on the Binet scale.

• 1914 : testified in court that people with below-average intelligence should have limited criminal responsibility.

Dispersion between and within individuals

• Thurstone asserted that perceptions have distributions between and within individuals. i.e. Not only different people have different perceptions. The same person may see things differently at different time.

• The same principle applies well to other types of measurement. i.e. By chances you may get a "C" in the mid-term but an "A" in the final.

G Factor• All standardized tests of academic aptitude or

achievement measure this general factor to some degree, but IQ test expressly designed for that purpose--measure it more accurately (Spearman, 1904)

• At the turn of the 20th century Charles Spearman (1863-1945) used statistical methods such as Correlation and Factor Analysis to define mental abilities as factors.

• When two apparently different abilities are shown to be highly correlated, Spearman took this as an evidence for the existence of a general factor G.

Other views• Thorndike: intelligence contains several unique

factors• Thurstone: seven uncorrelated factors. • Guilford: three factors.• The Wechsler Adult Intelligence Scale – fourth

edition (WAIS-IV): 4 dimensions– verbal comprehension (VCI)– perceptual reasoning (PRI)– working memory (WMI)– processing speed (PSI)

Multiple Intelligences

• Gardner asserted that there are eight dimensions of intelligence and all eight intelligences are of equal intrinsic value. It is the culture and social context that determine the value and importance of the dimension.

• Scientists from the University of Sheffield, England, provided evidence that numerical reasoning and linguistic ability may be two independent entitles. They examined several patients who suffered severe damage to the language faculty of their brains, and found that their mathematical ability is intact.

Linguistic

Logical-mathematical

Interpersonal

Intrapersonal

Artistic-spatial

Musical

Kinesthetic

Naturalist

Assignment

• Form a group of 3 to 4 people to discuss the following issue: The current Wechsler IQ test covers four aspects: Verbal comprehension, perceptual reasoning, working memory, and processing speed. Gardner maintained that intelligence has eight dimensions. However, some people argued that some dimensions of Gardner’s model is “untestable” or too difficult to measure, such as interpersonal, intrapersonal, and naturalistic, and therefore we should adopt the Wechsler’s model rather than the Gardner’s model in standard assessments.

How do people misuse/misinterpret tests?

• A human mind is compared to a physical body, which is composed of different faculties (muscles)

• In weight training the motion itself achieves nothing but to make you like Arnold Schwarznegger.

• Some learning materials may be irrelevant and inapplicable, but taking difficult tests like GRE can make you as smart as Albert Einstein.

IQ Test and Bell Curve• Herrnstein and Murray (1994)

found that in IQ tests Jews and East Asians, on the average, outperform European Americans, and the mean score of White Americans is higher than Blacks.

• The bell-curve (a spread of ability) exists in spite of intervention (e.g. education, affirmative action...etc)

IQ Test and Bell Curve

• Philosopher Clark Glymour (1998) gave a philosophical argument against the bell curve theory in "What went wrong? Reflections on science by observation and the bell curve", Philosophy of Science, 65, 1-32. The major argument is that an observed statistical property is not qualified to be a causal inference.

IQ Test and Bell Curve

• Reviewing the intelligence debate at its meeting of November 1994, the Board of Scientific Affairs of the American Psychological Association established a Task Force charged with preparing a report (Neisser et al., (1996). "Intelligence: Knows and unknowns". American Psychologist, 51, 77-101) to examine the claims made by Herrnstein and Murray.

U.S.--East Asian ability differences• Geary, D. C., Salthous, T. A., Chen, G. P., and Fan, L.

(1994). Numerical cognition: Are U.S.--East Asian ability differences a recent phenomenon?

• Younger and older adults from the U.S. and China were tested.

• It indicated no consistent ability differences, except the younger Chinese adults substantially outperformed the younger Americans in arithmetic.

• The overall pattern suggests that the advantage of Chinese adults over American adults in arithmetic is a recent phenomenon.

SAT and Expenditures

• The data published in the Wall Street Journal (June 22, 1995) shows the rank of each state's average SAT score and average expenditure on education. Unfortunately, the data "show" the more a state spends, the worse (on average) their SAT rank is. Does this mean spending less on education will improve SAT rank?

SAT and Expenditures• Problems with this analysis:

– State level data may not be true within states.

– Cost of living (and therefore expenditures) varies across the country.

– Not everyone takes the SAT. Ecological fallacy

• What happens when we look at data from the National Assessment of Education Progress (NAEP) that a) was designed to measure achievement, and b) is taken by a representative sample? On contrary to the data on the Wall Street Journal, there is a positive relationship between NAEP and expenditures.

SAT and Expenditures

• Moral of the story: We cannot afford to be ignorant about how testing is used in our society, even if we do not want to use such tests in our classroom.

Flynn effect

• IQ test scores have been continuously increasing since the earliest years of testing.

• Why?

Grade decline• SAT scores in reading, writing and math decline in 2011

compared to 2010, and have been gradually declining for years. Critical reading scores are the lowest in 40 years.

• In 2006 the SAT added a writing section to the verbal and math parts. Since then the average scores are down 6 points for reading; 4 points for math and 8 points for writing.

• U.S. Department of Education reviewed student transcripts from 3,000+ universities and found that student grades have actually declined slightly over the last 20 years.

Assignment

• Form a group consisting of 3-4 people. One or two must have a Web-enabled laptop.

• Access the APU library and the Internet

• Discussion: Is grade decline (e.g. SAT) incompatible with the Flynn effect? How would you explain this contradiction?

• Submit a 1-2-page report to Sakai and present a verbal report in class