Intelligence and Measurement Notes

Objectives

  • Define intelligence.
  • Describe the tools used to measure intelligence.
  • Discuss the issues in the assessment of intelligence.

Outline

  • Introduction
  • Intelligence
  • Measuring Intelligence
  • A Perspective
  • Measurement

What is Intelligence?

  • Intelligence is a complicated ability that shows up in several ways during the lifespan.
  • Generally speaking, intelligence encompasses different skills such as:
    • gaining
    • using knowledge
    • to reason rationally
    • to make an effective plan
    • to make wise decisions
    • to resolve issues
    • to comprehend ideas
    • to pay attention
    • to have intuition
    • to manage
    • to adapt

Intelligence Is…

  • Memory, concentration, and attention are combined when a person is required to repeat numbers presented orally.
  • It is difficult to say how much memory and concentration is needed for a successful solution.
  • Binet referred to better methods of assessing intelligence.
  • Binet never well-defined intelligence, he described its components in terms of thinking, deciding, remembering, and comprehending ideas (Varon, 1936).
  • In Galton's method of measuring intelligence, Binet and a colleague asked for more accurate measures of intelligence ability (Binet & Henri, 1895a, 1895b, 1895c).
  • Galton envisioned Intelligence as a set of various processes or abilities which can be assessed only by separate tests.
  • Binet argued that when one deals with a precise issue, skills employed can't be distinguished, since they operate to produce the solution.

Perspective on Intelligence

  • Louis L. Thurstone envisioned intelligence as consisting of what he called primary mental capacities (PMAs).
  • Thurstone (1938) constructed and released the Primary Mental Abilities test, which had various tests, each of which tried out one PMA: verbal meaning, perceptual speed, reasoning, number facility, rote memory, word fluency, and spatial relations.
  • Although the test wasn't utilized much; this initial version was based on several abilities that encouraged other test developers and theorists to explore alternative elements of intelligence and methods of quantifying them.

Factor-Analytic Theories of Intelligence

  • Factor analysis is a group of statistical methods aimed at establishing the presence of underlying associations among sets of variables, like test scores.
  • Theorists invoke factor analysis to explore correlations between tests measuring varied abilities presumed to access the underlying attribute of intelligence.
  • Charles Spearman introduced new methods to verify how varying tests correlate with one another in 1904.
  • Spearman (1927) systematized these observations into a powerful idea regarding general intelligence that argued that there's a general intellect factor that is partly measured by all other mental capacities.
  • This theory has also been called a two-factor theory of intelligence, where the extent of common variance on all intelligence tests is common and the remaining portions of the variance being accounted for either by specific components, or by error components of this general factor.

Spearman's Two-Factor Theory

  • General Intelligence
  • Specific Abilities

Interpersonal Intelligence

  • Interpersonal intelligence is the capacity to comprehend other individuals: what drives them, how they work, how to work with them in cooperation.
  • Effective salespeople, politicians, educators, clinicians, religious leaders are likely to be persons with high levels of interpersonal intelligence.

Cattell’s Theory

  • Intelligence has two main types:
    • Crystallized intelligence:
      • What you learn from school, books, and life experience—like vocabulary or general knowledge.
    • Fluid intelligence:
      • Your natural problem-solving ability—like solving puzzles or remembering numbers, which doesn’t depend on education.

Carroll’s Three-Stratum Theory

  1. General intelligence (g) at the top
  2. Eight broad abilities in the middle (like memory, reasoning, etc.)
  3. Specific skills, like speed or difficulty level, at the bottom
  • Psychological theories reveal layers of mental abilities, just like erosion shows layers of rock.

Cattell-Horn and Carroll Models

  • The Cattell-Horn and Carroll models of intelligence are similar because both include broad abilities made up of narrower skills.
  • Key differences:
    • Carroll’s model includes a top level called g (general intelligence), which affects all other abilities.
    • Cattell-Horn’s model does not include g—it focuses only on broad and narrow abilities.
    • Cattell-Horn sees quantitative knowledge and reading/writing as major (broad) abilities; Carroll sees them as smaller, narrow skills.
  • Kevin McGrew (1997) helped combine both models into one big, modern theory called the CHC model, which is now widely used.

The Information-Processing View

  • Aleksandr Luria studied how people process information, not just what they know.
  • Two main ways our brain works:
    1. Simultaneous (or parallel) processing
      • This is when your brain puts different pieces of information together all at once to get the big picture.
      • Example: Looking at a map to understand where everything is located. Your brain takes in all the info at the same time to figure it out.
    2. Successive (or sequential) processing
      • This is when your brain works step-by-step, in order.
      • Example: Trying to figure out who the killer is in a crime show by following each clue one after another.
      • Another example: Remembering a phone number by repeating it in the correct order.
  • Most people use simultaneous thinking.
  • Researchers Das and Naglieri used this idea in the PASS model of intelligence.
  • PASS stands for:
    1. Planning – Making a strategy to solve a problem
    2. Attention – Focusing and staying alert to information
    3. Simultaneous processing – Putting info together all at once
    4. Successive processing – Processing info step-by-step
  • This model explains how different mental processes work together in thinking and learning.

Stanford-Binet Intelligence Test

Historical Context

  • The Stanford-Binet Intelligence Scales, developed by Alfred Binet and Theodore Simon in 1905, are the world's first formal intelligence test.
  • Adaptations and translations emerged globally, with the original Binet-Simon Scale used in the US as early as 1908.
  • Terman's 1916 English translation of the Binet- Simon test, a significant milestone in Stanford- Binet's history, introduced new test items and a methodological approach, boosting worldwide interest in intelligence tests.

Early Innovations and Revisions

  • The Stanford-Binet was the first intelligence test to provide detailed administration and scoring instructions, employ the concept of IQ, and introduce alternate items.
  • Its 1937 revision, started in 1926 and it took 11 years to complete, introduced new forms and tasks for both preschool and adult test-takers.
  • Despite initial flaws, the test was praised for its technical achievement in validity and reliability, but faced criticism for its lack of representation of minority groups.
  • Early versions of the Stanford-Binet employed the ratio IQ as a way to quantify intelligence.
  • The ratio IQ was based on the concept of mental age.
  • Mental age refers to the age level at which an individual is functioning intellectually, as indicated by the level of test items they could answer correctly.
  • The ratio IQ was calculated by dividing the test-taker's mental age by their chronological age and then multiplying the result by 100.

Stanford-Binet Fifth Edition (SB5)

  • The Stanford-Binet (SB5) is a cognitive assessment tool designed for individuals aged 2 to 85.
  • It produces composite scores, including a Full Scale IQ, Abbreviated Battery IQ, Verbal IQ, and Nonverbal IQ.
  • The test also provides five Factor Index scores for each of the five factors it measures.
  • Based on the Cattell-Horn-Carroll (CHC) theory of intellectual abilities, the SB5 measures five CHC factors through different tasks and subtests at different levels.

The Stanford-Binet 5th Edition (SB5)

  • An individually administered intelligence test designed to assess various cognitive abilities in individuals from age 2 to over 85.
  • The SB5 is based on the Cattell-Horn- Carroll (CHC) theory of intellectual abilities.
  • It aims to provide a balanced assessment of both verbal and nonverbal skills.

CHC and Corresponding SB5 Factors

  • SB5 Factor Name, CHC Factor Name, Brief Definition, Sample SB5 Subtest
    • Fluid Reasoning (FR), Fluid Intelligence (Gf), Novel problem solving; understanding of relationships that are not culturally bound, Object Series/Matrices (nonverbal) Verbal Analogies (verbal)
    • Crystallized Knowledge (KN), Knowledge (GC), Skills and knowledge acquired by formal and informal education, Picture Absurdities (nonverbal) Vocabulary (verbal)
    • Quantitative Reasoning (QR), Quantitative Knowledge (Gq), Knowledge of mathematical thinking including number concepts, estimation, problem solving, and measurement, Verbal Quantitative Reasoning (verbal) Nonverbal Quantitative Reasoning (nonverbal)
    • Visual Processing (GV), Visual-Spatial Processing (VS), Ability to see patterns and relationships and spatial orientation as well as the gestalt among diverse visual stimuli, Position and Direction (verbal) Form Board (nonverbal)
    • Short-Term Memory (WM), Memory (Gsm), Cognitive process of temporarily storing and then transforming or sorting information in memory, Memory for Sentences (verbal) Delayed Response (nonverbal)

The Stanford-Binet 5th Edition (SB5)

  • Measures cognitive factors like Fluid Intelligence, Crystallized Knowledge, Quantitative Knowledge, Visual Processing, and Short- Term Memory, using corresponding subtests.
  • The SB5 test demonstrates high reliability and validity, though debate exists on its factor structure.
  • Test administration involves rapport building, routing tests, determining item levels, and adhering to rules.
  • Scoring converts raw scores to standard, and interpretation includes profile analysis and behavioral observation.
  • Future revisions may include design and use changes.

David Wechsler Test

  • Born in Romania, David Wechsler a prominent psychologist who recognized the limitations of existing intelligence tests, particularly the Stanford- Binet, in accurately assessing the diverse population he encountered at Bellevue Hospital in Manhattan during the 1930.
  • Wechsler sought to create a test that would be more suitable for a multilingual and multicultural population, moving away from age- based norms and focusing on a broader range of cognitive abilities

Wechsler-Bellevue Intelligence Scale (W-B)

  • A point scale organized by subtests rather than age groups.
  • The W-B featured 11 subtests, encompassing both verbal and performance tasks, designed to provide a more comprehensive evaluation of intelligence.
  • The W-B, though a significant advancement, faced some limitations, including a restricted standardization sample and questionable inter-item reliability in certain subtests.

Wechsler Adult Intelligence Scale (WAIS)

  • WAIS, 1955
  • WAIS-R, 1981
  • WAIS-III, 1997

WAIS-III, 1997

  • Extended norms to include individuals aged 74-89 and incorporated a greater sensitivity to cultural bias.
  • It also introduced four Index Scores: Verbal Comprehension, Perceptual Organization, Working Memory, and Processing Speed.

WAIS-IV (2008)

  • It includes ten core subtests that are administered to obtain a composite score and five supplemental subtests (also sometimes referred to as an optional subtest) are used for purposes such as providing additional clinical information or extending the number of abilities or processes sampled.

WAIS-IV (2008)

  • There are, however, situations in which a supplemental subtest can be used in place of a core subtest.
  • The latter types of situations arise when, for some reason, the use of a score on a particular core subtest would be questionable.
  • A supplemental subtest might be substituted for a core subtest if:
    • the examiner incorrectly administered a core subtest
    • the assessee had been inappropriately exposed to the subtest items prior to their administration
    • the assessee evidenced a physical limitation that affected the assessee’s ability to effectively respond to the items of a particular subtest

WAIS-IV (2008)

  • Expanded norms to include test-takers up to age 90 years, 11 months, and incorporates features that make the test more accessible to older adults.
  • Other changes in the WAIS-IV as compared to the previous edition of this test reflect greater sensitivity to the needs of older adults.

WAIS-IV (2008) Improvements

  • Enlargement of the images in the Picture Completion, Symbol Search, and Coding subtests
  • The recommended non-administration of certain supplemental tests that tap short-term memory, hand-eye coordination, and/or motor speed for test takers above the age of 69 (this is to reduce testing time and to minimize test taker frustration)
  • An average reduction in overall test administration time from 80 to 67 minutes (accomplished primarily by shortening the number of items the test taker must fail before a subtest is discontinued)

WAIS-IV Subtests Grouped According to Indexes

  • Verbal Comprehension Scale:
    • Similarities
    • Vocabulary
    • Information
    • Comprehension
  • Perceptual Reasoning Scale:
    • Block Design
    • Matrix Reasoning
    • Visual Puzzles
    • Picture Completion
    • Figure Weights (ages 16-69)
  • Working Memory Scale:
    • Digit Span
    • Arithmetic
    • Letter-Number Sequencing (ages 16-69)
  • Processing Speed Scale:
    • Symbol Search
    • Coding
    • Cancellation (ages 16-69)

Short Forms of Intelligence Tests

  • The term short form refers to a test that has been abbreviated in length, typically to reduce the time needed for test administration, scoring, and interpretation.
  • David Wechsler endorsed the use of short forms in 1958 but only for screening purposes.
  • Wechsler advised those claiming that they did not have the time to administer the entire test to “find the time” (Wechsler, 1967, p. 37).
  • Silverstein (1990) provided an incisive review of the history of short forms, focusing on four issues:
    1. how to abbreviate the original test
    2. how to select subjects
    3. how to estimate scores on the original test
    4. the criteria to apply when comparing the short form with the original

Group Test of Intelligence

  • On April 6, 1917, the United States declared war, and the following day, Robert M. Yerkes, the president of the American Psychological Association (APA), took immediate action to involve psychologists in the war effort.
  • By the end of May 1917, a committee formed by the APA convened to develop group intelligence tests for military use.
  • There was little debate regarding the definition of intelligence among the committee members; instead, the primary concern was the urgent need to create tests that could efficiently identify soldiers who were either "unfit" for service or possessed "exceptionally superior ability."

Types of Group Intelligence Tests

  • Army Alpha Test
  • Army Beta Test
  • ASVAB (Armed Services Vocational Aptitude Battery)
  • Armed Forces Qualification Test (AFQT)
  • California Test of Mental Maturity
  • Henmon-Nelson Tests
  • Otis-Lennon School Ability Test

Explanation of Group Tests by Yerkes

  • In 1921, Yerkes offered the following explanation of what he believed the tests measured: The tests give a reliable index of a man’s ability to learn, to think quickly and accurately, and to comprehend instructions. They do not measure loyalty, bravery, dependability, or the emotional traits that make a man “carry on.” A man’s value to the service is measured by his intelligence plus other necessary qualifications. (p. 424)

Cognitive Style

  • A cognitive style is a psychological dimension that characterizes the consistency with which one acquires and processes information (Ausburn & Ausburn, 1978; Messick, 1976).
  • Examples of cognitive styles include Witkin et al.’s (1977) field dependence versus field independence dimension, the reflection versus impulsivity dimension (Messer, 1976), and the visualizer versus verbalizer dimension (Kirby et al., 1988; Paivio, 1971).

Advantages and Disadvantages of Group Tests

  • Advantages of Group Tests
    • Large numbers of test-takers can be tested at one time, offering efficient use of time and resources.
    • Test-takers work independently at their own pace.
    • Test items are typically in a format easily scored by computer or machine.
    • The test administrator need not be highly trained, as the task may require little beyond reading instructions, keeping time, and supervising test takers.
    • The test administrator may have less effect on the examinee's score than a test administrator in a one-on-one situation.
    • Group testing is less expensive than individual testing on a per-test-taker basis.
    • Group testing has proven value for screening purposes.
    • Group tests may be normed on large numbers of people more easily than an individual test.
    • Group tests work well with people who can read, follow directions, grip a pencil, and do not require a great deal of assistance.
  • Disadvantages of Group Tests
    • All test-takers, regardless of ability, typically must start on the same item, end on the same item, and be exposed to every item on the test. The opportunity for adaptive testing is minimized.
    • Test-takers must be able to work independently and understand what is expected of them, with little or no opportunity for questions or clarification once testing has begun.
    • Test items may not be in more innovative formats or any format involving examiner manipulation of materials or examiner-examinee interaction.
    • The opportunity for assessor observation of test taker's extra-test behavior is lost.
    • The opportunity for learning about assessee through assessor-assessee interaction is lost.
    • The information from a group test may not be as detailed and actionable as information from an individual test administration.
    • Instruments designed expressly for screening are occasionally used for making momentous decisions.
    • In any test-taking situation, test takers are assumed to be motivated to perform and follow directions. The opportunity to verify these assumptions may be minimized in large-scale testing programs. The test taker who "marches to the beat of a different drummer" is at a greater risk of obtaining a score that does not accurately approximate his or her hypothetical true score.
    • Group tests may not work very well with people who cannot read, who cannot grip a pencil (such as very young children), who "march to the beat of a different drummer" or who have exceptional needs or requirements.

Measures of Creativity

  • Originality
  • Flexibility
  • Fluency
  • Elaboration

Convergent Thinking

  • Convergent thinking is a deductive reasoning process that entails recall and consideration of facts as well as a series of logical judgments to narrow down solutions and eventually arrive at one solution.

Divergent Thinking

  • Divergent thinking is a reasoning process in which thought is free to move in many different directions, making several solutions possible.
  • Divergent thinking requires flexibility of thought, originality, and imagination.

Issues in the Assessment of Intelligence

  • Measured intelligence may vary as a result of factors related to the measurement process.
    • Test author’s definition of intelligence
    • Examiner’s diligence
    • Amount of feedback the examiner gives the examinee
    • Previous practice or coaching of examinee
    • Competence of test data interpreter
    • Other influencing factors

Culture and Measured Intelligence

  • A culture provides specific models for thinking, acting, and feeling.
  • Culture enables people to survive both physically and socially and to master and control the world around them.
  • Because values may differ radically between cultural and sub cultural groups, people from different cultural groups can have radically different views about what constitutes intelligence
  • Culture loading refers to the extent to which a test incorporates culture-specific vocabulary, concepts, and knowledge

Culture Fair Test

  • Aims to measure abilities without being influenced by cultural or environmental biases

Culture-Fair Intelligence Test

  • Aims to minimize cultural influence by using simple, clear directions and nonverbal tasks that reflect common experiences and skills across cultures.

The Flynn Effect

  • A shorthand reference to the progressive rise in intelligence test scores that is expected to occur on a normed test intelligence from the date when the test was first normed.
  • The rise in measured IQ is not accompanied by any academic dividend and so is not thought to be due to any actual rise in “true intelligence."

The Construct Validity of Tests of Intelligence

  • The evaluation of a test’s construct validity proceeds on the assumption that one knows in advance exactly what the test is supposed to measure.
  • For intelligence tests, it is essential to understand how the test developer defined intelligence.

Summary

  • Intelligence is the ability to reason, solve problems, and adapt, is assessed through tests like the Stanford- Binet (SB5) and Wechsler Adult Intelligence Scale (WAIS), though these have limitations.
  • They often overlook individual differences and creativity, which tests like the Remote Associates Test (RAT) and Torrance Tests of Creative Thinking (TTCT) try to address.
  • However, intelligence remains too complex to be fully measured by a single test.