week 7 intelligence Flashcards
Intelligence Tests: Construct Validity
Need to know how test developer defined intelligence, for example:
Spearman’s g:
Factor analysis should yield a single large common factor that indicates the different questions or tasks largely reflected the underlying characteristic (g).
Thurston’s PMA theory
No single factor should be expected to dominate, but instead many different factors reflecting a diverse set of abilities.
CHC model
Expect hierarchical structure- basis for many modern IQ tests
Revision: CHC Hierachical Model
Stratum 111 Pervasive “g” general intelligence
Stratum 11 Broad Carroll’s list (others have added) Fluid IQ/Reasoning (Gf) Crystallised IQ/Knowledge (Gc) Domain Specific Knowledge (Gkn) Visual/Spatial (Gv) Broad Retrieval/Memory (Gr) Cognitive Processing Speed (Gs) Decision/Reaction Time (Gt) Auditory Processing (Ga)
Stratum 1 Specific Carroll’s list (others adding to it)
- approx. 70 specific abilities, e.g., general verbal knowledge (Gc narrow ability)
Summary of Stratum II (Conceptual Groupings)
Motor > Gp (psychomotor abilities
Perception > Gv, Gk, Ga, Go, Gh
Fluid Reasoning > Gf, Gsm(short-term mem)
Knowledge > Gc, Gq, Grw
Speed > Gps (psychomotor speed), Gt(speed of percept), Gs(attentional Fluency), (Glr) Learning Efficiency & retrieval fluency
Tests Informed by CHC Model
Kaufman & Kaufman (2004)
- revised KABC-II
- CHC primary organisational structure
Elliott (2007)
- revised Differential Abilities Scales (DAS-II)
- heavy CHC influence
WISC-IV (2003), WISC-V (2016), and WAIS-IV (2008)
- heavy influence by CHC theory
Woodcock-Johnson III (2001, 2007)
- heavy influence by CHC
Stanford-Binet V5 (2003)
- heavy influence by CHC
Measuring Intelligence: The Beginning
Binet’s revolution
Binet-Simon Intelligence Scale- first practical intelligence scale
Scored by identifying what 75% of an age group could answer.
30 individual tasks
Easy- name various body parts
More difficult- how are a rabbit and a bird different?
Construct a sentence from words
Remember digits
Draw a design from memory (below)
Evolution of the Binet Scale
The Stanford-Binet Intelligence Scales
The first published intelligence test with clear instructions on use
The first test to introduce the concept of an alternate item
Ratio IQ: the ratio of the test-taker’s mental age divided by his or her chronological age, multiplied by 100 to eliminate decimals:
RATIO IQ = Mental age/chronological age x 100
What is each child’s ratio IQ?
Fred has a mental age of 6 years, and a chronological age of 6 years.
MA/CA X 100 = 6/6 X 100 = 100
Charlie has a mental age of 10 years and a chronological age of 8 years.
MA/CA X 100 = 10/8 X 100 = 125
Charlie stays two years ahead, what is his ratio IQ when he is 10 years of age?
MA/CA X 100 = 12/10 X 100 = 120
Standford-Binet-III
Third edition changes:
Deviation IQ replaced the ratio IQ
Deviation IQ: a comparison of the performance of the individual with the performance of others in the same age in the standardisation sample
Fourth Edition:
Point scale implemented
Subtests organised by category of item rather than the age
Stanford-Binet-5
The fifth edition was designed for administration from ages 2 to 85
Upward extension to test adults over time
The test yields a number of composite scores, including a Full Scale IQ, an Abbreviated Battery IQ score, a Verbal IQ score, and a Nonverbal IQ score
Draws from CHC model
CHC and Corresponding SB5 Factors
see slide 12 for picture
Weschler Tests
Wechsler dissatisfied with Stanford-Binet (designed for children originally)
devised Wechsler Adult Intelligence Scale (WAIS)
age range 16+ yrs
Downward extensions of WAIS due to popularity to allow assessment of children
Wechsler Intelligence Scale for Children (WISC)~ age range ~ 7-16 yrs
Wechsler Pre-school/Primary Scale Intelligence (WPPSI) ~ age range 3-7 yrs
Earlier versions very similar
Wechsler Tests
are what?
and work under what premise?
Individually administered
(a) assess different aspects of ability (b) give opportunity to view personality, motivation, and other variables
Work under the premise that:
Intelligence is both global and specific
Aspects of intelligence cluster into higher-order
cognitive ability domains
Subtests are different measures of intelligence, not
measures of different kinds of intelligence
Until recently, all Wechsler scales yielded a Full Scale IQ (a measure of general intelligence), a Verbal IQ, and a Performance IQ
-Recent revisions greater informed by CHC and factor analysis
Sample Similar Tasks (Sattler, 2016)
Block design: reproduce designs using 2, 4 or 9 blocks
Similarities: “In what way are a pencil and a piece of chalk alike?”
Matrix Reasoning: complete the series
Digit Span: repeat digits forwards, backwards, and in order
Coding: Quickly copy symbols from a code in a set time
Sample Similar Tasks (Sattler, 2016) part 2
Figure weights: Select choice that balances scale
Visual Puzzles: Select three pieces that make the design
Picture Span: Look at one+ nameable objects then find in a set with other pictures
Symbol Search: Quickly find and indicate if a symbol is present in an array
Vocabulary: e.g., “What is a ball?”
WAIS Evolution
WAIS stands for what?
1939 – original Wechsler-Bellevue Intelligence Scale
1955 – Wechsler Adult Intelligence Scale (WAIS)
1981 – WAIS-R
1997 – WAIS-III (3rd Ed)
. to this point, almost 80% original
. improvements in presentation and focus on cultural fairness
2008 – WAIS-IV
substantial changes (reflect CHC developments)
~ new subtests, some subtests dropped
~ dropped PIQ and VIQ composites
~ normed with WMS (What is expected memory functioning given IQ?)
WAIS-III (1997): Structure
organisation identified via factor analyses (a) “g” factor (b) verbal and performance factors (c) four indices (factors) . verbal comprehension . working memory . perceptual organisation . processing speed (d) 14 subtests (2-3 per factor/index)
WAIS-IV (2008)
see slide 21
CHC Theory & WAIS
Stratum 111 Pervasive “g” general intelligence
Stratum 11 Broad Fluid IQ/Reasoning (Gf) Crystallised IQ/Knowledge (Gc) Domain Specific Knowledge (Gkn) Visual/Spatial (Gv) Short-term Memory (Gsm) Cognitive Processing Speed (Gs) Decision/Reaction Time (Gt) Auditory Processing (Ga)
Stratum 1 Specific - some specific abilities
Weschler Intelligence Scale for Children (WISC)
Many revisions over the years WISC 1949 WISC-R 1974 WISC-III 1991 WISC-IV 2003 WISC-V 2016
WISC-V designed for assessment of children aged 6:0 -16:11
WISC-V Overview
10 primary subtests
Full Scale IQ (FSIQ) and the five primary index scores
Perceptual reasoning now split into visual spatial and fluid reasoning
6 secondary subtests
Ancillary and expanded index scores
Substitute for a primary subtest in calculation of FSIQ if admin is spoiled
(5 complementary subtests- US/Q-interactive only)
Only on Q-interactive (iPad) administration
US norms