IQ

Examples of IQ in the following topics:

• Tilting the Tests: Discrimination by IQ

  • IQ is meant to measure intelligence but its validity as a measure of intelligence has been debated.
  • Yet these IQ gaps are only observed in average scores and say very little about individuals.
  • Plus, IQ scores show considerable overlap between these group scores, and individuals of each group can be found at all points on the IQ spectrum.
  • Thus, the implications of the IQ gaps are unclear.
  • Alfred Binet was a French psychologist who invented the IQ test.

• IQ Tests

  • Currently, IQ tests are used to study distributions in scores among specific populations.
  • Scores on IQ tests tend to form a bell curve with a normal distribution.
  • There are a wide variety of IQ tests that use slightly different tasks and measures to calculate an overall IQ score.
  • Currently, most tests tend to measure both verbal and performance IQ.
  • All of these measures and tasks are used to calculate a person's IQ.

• Controversies in Intelligence and Standardized Testing

  • They also cast doubt on the validity of IQ tests and whether IQ tests actually measure what they claim to measure—intelligence.
  • Researchers have learned that IQ and general intelligence (g) correlate with some social outcomes, such as lower IQs being linked to incarceration and higher IQs being linked to job success and wealth.
  • For example, the relationship between wealth and IQ is well-documented.
  • Could this mean that IQ tests are biased toward wealthy individuals?
  • IQ tests are often criticized for being culturally biased.

• History of Intelligence Testing

  • He created and published the first IQ test in the United States, the Stanford-Binet IQ test.
  • The Wechsler scales contained separate subscores for verbal IQ and performance IQ, and were thus less dependent on overall verbal ability than early versions of the Stanford-Binet scale.
  • In the normal population, g and IQ are roughly 90% correlated.
  • In order to develop an IQ test that separated environmental from genetic factors, Raymond B.
  • The bell shaped curve for IQ scores has an average value of 100.

• Genetic Basis of Intelligence and Learning

  • There has been significant controversy in the academic community about the heritability of IQ, or Intelligence Quotient, which seeks to determine to what extent an individual's IQ level is influenced by genetics.
  • Studies show that there are some family/environmental effects on the IQ of children; however adoption studies show that, by adulthood, adoptive siblings are not more similar in IQ than strangers, while adult full siblings show higher similarities in IQ, even when raised separately.
  • Conventional twin studies reinforce this pattern: monozygotic (identical) twins raised separately are more similar in IQ than dizygotic (fraternal) twins raised together, and much more than adoptive siblings.

• Genetic and Environmental Impacts on Intelligence

  • Twin studies in the western world have found the heritability of IQ to be between 0.7 and 0.8, meaning that the variance in intelligence among the population is 70%-80% due to genetics.
  • However, the heritability of IQ in juvenile twins is much lower at 0.45.
  • Thus, despite the high heritability of IQ, we can determine that there is an environmental influence as well.
  • A group of largely African American, urban first-grade children and their caregivers were evaluated using self-report, interview, and standardized tests, including IQ tests.
  • The study reported that exposure to violence and trauma-related distress in young children was associated with substantial decreases in IQ and reading achievement. 

• Introduction

  • Most IQ scores are normally distributed.

• The Gifted

  • Since the early 20th century, definitions of "gifted" have been based on IQ, or intelligence quotient.
  • Different schools may set different cut-offs for defining giftedness, but a common standard is the top 2% of students with an IQ score of about 140 or above.
  • Early IQ tests were notorious for producing higher IQ scores for privileged races and classes and lower scores for disadvantaged subgroups.
  • Although IQ tests have changed substantially over the past half century, and many objections to the early tests have been addressed by "culture neutral," IQ testing remains controversial.

• Group Differences in Intelligence

  • Before IQ testing was developed, scientists used to rely on crude data such as head or brain size or reaction times to estimate intelligence levels.
  • It was not until Alfred Binet and the emergence of the IQ test that psychologists were able to collect data that could accurately and reliably compare human groups .
  • Since the advent of reliable and valid IQ testing methods, psychologists have demonstrated, and the APA has declared, that differences in group intelligence are undeniable.
  • During the early years of research, raw scores on IQ tests systematically rose throughout the world.
  • It is possible that the very composition of certain IQ tests can allow or inhibit certain levels of performance among different groups.

• The Supreme Court Revisits Affirmative Action

  • After the passage of the Civil Rights Act in 1964, the company removed the racial restriction, but retained the high school diploma requirement, and added the requirement of an IQ test, with the racist belief that African Americans would score lower than whites on an IQ test.
  • The Supreme Court ruled that under Title VII of the Civil Rights Act, if the IQ and diploma tests disparately impacted ethnic minority groups, businesses must demonstrate that such tests are "reasonably related" to the job for which the test is required.