David Wechsler was especially sensitive to non-intellectual factors and influence on test scores. What are non-intellectual factors? Provide examples.
Non-intellectual Factors
Ex. Attitude, emotional functioning, experience, motivation, effort, persistence, leadership skills, etc…
Describe the point scale concept.
A test in which points (0, 1, or 2) are assigned to each item. The advantage of the point scale, is that all items with a particular content can be grouped together. Items ordered in increasing difficulty level (0,1,2) by content.
What is verbal IQ?
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What is performance IQ?
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Describe the performance scale concept.
A scale that provided a measure of nonverbal intelligence. The performance scale consisted of tasks that require a subject to do something (ex. copy symbols) rather than merely answer questions
- Know Wechsler’s definition of intelligence
“Act purposefully, think rationally/logically, effectively deal with environment”
- Know 4 Factors/Indices
- Verbal comprehension
- Perceptual organization/reasoning
- Working memory
- Processing speed
- Know the mean and standard deviation of the SCALED scores
Mean=10, SD=3
- Know Means and Standard deviations for the Verbal IQ, Performance IQ, and the 4 Indices
Verbal: Mean=100, SD=15
Performance: Mean=100, SD=15
4 Indices: Mean=100, SD=15 (derived by summing the scaled scores that make up that index)
What are the psychometric properties of the WAIS-IV? (participants, reliability, and validity)
Participants: 2200 adults; 13 age groups (16-90); stratified based on 2005 census data, also included specialty groups
Reliability: .98 FSIQ, .95 PRIQ, .94 WM, .90 PS —split half or internal consistency reliability coefficients; test-retest reliability coefficients only slightly lower
Validity: Considered “among the most valid” when looking at different types of validity
- Know the pros/cons of the alternative ability tests
Cons
- Weaker standardization sample (not as representative as binet or wechsler)
- Less stable
- Less documentation on validity
- Limitations in test manual (some do not have detailed standard administration instructions)
- Not as psychometrically sound
- IQ scores not interchangeable with Binet or Wechsler
Pros
- Can be used for specific populations and special purposes (sensory limitations–physical limitations–language limitations–culturally deprived people–foreign born individuals–non English speaking people)
- Not as reliant on verbal responses
- Not as dependent on complex visual-motor integration
- Useful for screening, supplement, and reevaluations
- Can be administered nonverbally (using a performance scale)
- Not highly correlated with scholastic achievement (this is because reading ability is not emphasized on the alternatives)
What is the Bender Visual Motor Gestalt Test and what does it measure?
The Bender Visual Motor Gestalt Test (BVMGT) is a Visiographic Neuropsychological Test used to asses brain damage
- Participant is asked to copy 9 geometric figures
* One of the most popular assessment instruments
What is meant by the factor analytic approach?
The factor analytic approach is an empirical strategy (“statistical strategy”)
-uses factor analysis to REDUCE data to a small number of traits/basic dimensions of personality
Example: If an aggression scale and a hostility scale highly correlate with each other (share common variance), they may be reduced to measuring one trait, which is paranoid personality
What is meant by the factor analytic approach?
The factor analytic approach is an empirical strategy (“statistical strategy”)
-uses factor analysis to REDUCE data to a small number of traits/basic dimensions of personality
*Therefore, it reduces redundancy
Example: If an aggression scale and a hostility scale highly correlate with each other (share common variance), they may be reduced to measuring one trait, which is paranoid personality
What is meant by the logical-content approach?
The logical-content approach is a deductive strategy. -Items are selected using logic and deductive reasoning
-It assumes that the test item describes the subject’s personality and behavior (Basically face validity which is no longer an acceptable form of validity)
Wechsler’s performance scale was the first to offer the possibility of directly comparing an individual’s verbal and nonverbal intelligence. Why can verbal and nonverbal intelligence be compared?
Both the verbal and nonverbal scales were standardized on the same sample and the results of both scales were expressed in comparable units.
What does the performance scale attempt to overcome?
Biases caused by language, culture, and education
What components of performance tasks provide clinicians with an opportunity to observe behavior in a standard setting?
They require a longer interval of:
- sustained effort
- attention
- concentration
The Verbal Comprehension Index includes 4 sub-tests: 1. Vocabulary 2. Similarities 3. Information 4. Comprehension What does each sub-test measure?
- Vocabulary: ability to define words; only more severe emotional problems/brain damage will influence this score because it is the most stable sub-test.
- Similarities: ability to see the similarity between apparently dissimilar objects or things; gives information about a person’s thought process (may reveal schizophrenia)
- Information: range of knowledge, curiosity, and cultural interests
- Comprehension: Judgement in everyday situations; common sense; may reveal emotional problems
The Perceptual Organization Index includes 4 sub-tests: 1. Picture Completion 2. Block Design 3. Matrix Reasoning 4. Visual Puzzles What does each sub-test measure?
- Picture completion: attention to detail and visual processing
- Block Design: Non-verbal reasoning and visual motor integration (it has a problem solving and abstract reasoning component as well, but that was Wechsler’s intention)
- Matrix Reasoning: Inductive Reasoning; also measures fluid intelligence, information processing, and abstract reasoning skills
- Visual Puzzles: strategy, integration, visual-spatial ability
The Working Memory Index includes 3 sub-tests: 1. Arithmetic 2. Digit Span 3. Letter-number Sequencing What does each sub-test measure?
- Arithmetic: concentration and working memory
- Digit Span: Immediate memory and anxiety (Note: repeating digits backwards requires working memory because you have to think about it rather than repeating exactly what you just heard.)
Letter-number Sequencing: working memory and attention; individual is given a mix of numbers and letters–>they must first list the numbers in order and then list the letters in alphabetical order
The Processing Speed Index includes 2 sub-tests:
1. Digit Symbol Coding
2. Symbol Search
What does each sub-test measure?
- Digit Symbol Coding: Visual Motor Functioning
2. Symbol Search: Visual Information Processing Speed
The Woodcock-Johnson III Tests of cognitive Abilities and Achievement Skills is one of the better tests used to detect learning disability. What 5 things does it evaluate?
- psychometric “G” (full scale IQ score)
- specific cognitive abilities
- scholastic aptitude
- oral language
- achievement
How is the Bender Visual Motor Gestalt Test scored, and what do poor scores indicate?
- It is scored according to the number of errors the participant makes
- Significant errors occur for people whose mental age is less than 9, have organic brain damage, have nonverbal learning disabilities, and/or have emotional problems
