Weschler Intelligence Scale for Children (WISC)
Assess present level of intellectual functioning. Most popular. Assess APTITUDE in age 6-16. Individual. Attempt all in one sitting. Done btwn examiner & child. Developed as a downward extension of the WISA (WAIT). Questions progress in difficulty. 2 groups of subtests: verbal & performance. Finish @ set # failures to decrease frustration. Performance highly correlated with success in school. Sub-tests scored 1-19. Three IQ scores given: Verbal IQ (VIQ), Performance IQ (PIQ) and Full Scale IQ.
Picture Completion (WISC)
Perf. subtest on WISC. Pic with part missing. (ex: coat with no buttons) Ch. must recognize representation of pic as item (coat) and that it is incomplete. Test ability to differentiate essential & non-essential features, visual memory. Finish @ 5 failures or 30 complete.
Ch. is asked questions that assess broad range of world/culture knwlg. (Ex: Point to arm - "What's this?") Assess how much knowledge, ability to acquire, retain & retrieve factual knwlg. Finish @ 5 failures. Verbal Subtest of WISC.
Perf sub-test. Ch. given a code (ex: 1-*, 2-%, 3-^). Then blank boxes to fill in the code. Timed/Speed. Scored on correct response in time limit. Fine motor, Visual processing, perceptual-motor coordination, memory, retention.
Verbal sub-test. Assess similarities of objects or concepts (ex: fork-spoon, happy-sad). Assess logical thinking skills, think abstractly with verbal abstract concepts. High score goes beyond the obvious aspects and responds with abstract thinking.
Picture Arrangement (WISC)
Perf sub-test. Asked to put pics in an order that would tell a story. Non-verbal. Bonus pts for speed. Shows ppl in social situations. Comprehend total situation, anticipate what next and judge cause & effect.
Verbal sub-test. Given a number of arithmetic problems (+,-,x,/) to solve in their head. Severe demands on working memory & reasoning ability. Timed. Must have numerical operations mastered to do well. May use combined operations in multi-step problems. Anxiety disrupts concentration.
Block Design (WISC)
Perf sub-test. Use blocks to recreate elaborate designs presented on paper. Increase in complexity. Assess visual perception, motor coordination and ability to appreciate the rltshp btwn parts of the design(choose right side). Sides: 2 red, 2 white, 2 half/half. Step by step process is recorded.
Verb sub-test. Tested on meaning of certain words. Start with familiar, concrete nouns to more abstract, less familiar words. Assess the fund of info available to ch. Indirectly assess cognitive function, richness of ideas, ability to form concepts, how well ch. learns.
Object Assembly (WISC)
Perf sub-test. Assemble puzzle pieces to form an object (familiar objects, no model given). 5 O.A.s. Tests ability to deal with anticipate part-whole relationships, visual-motor coordination. Speed important.
Verb sub-test. Asked questions on what to do or how to behave in practical day to day situations. Assess common sense reasoning, judgements, cultural wisdom, & social conventions. (ex: why do we wear shoes?)
Symbol Search (WISC)
Perf sub-test. Ch. searches for a target symbol among a list of other symbols. Visual-processing speed, retain symbol in memory (to not look back and forth). Tested on speed.
Digit Span (WISC)
Verb sub-test. Examiner states list of numbers and ch. asked to repeat list back. Gradually add numbers. Rote short-term memory. Then asked to repeat backwards. Working memory. Finish @ 2 failures. Attention to sequence, retain items (with unrelated material), operate on input and retrieve info.
Perf sub-test. Presented with mazes. Can't lift pencil. No going in blind alleys. Assess visual fine motor coordination, cognitive abilities like planning ahead, looking forward, anticipating.
Only a limited set of answers. Given all the info about the problem and the info needed to solve the problem. The WISC would assess skills of well-defined problems (Ex: 2+2=4, what colour?)
Ambiguous problems. What the problem is may not be immediately apparent. How to solve is unclear and there could be many possible solutions. (ex: buy car, why she crying, etc)
Standardization Sample (WISC)
WISC is sampled on a large group (2,200) (S.S.) Each age group gets their own sample (11 groups) Provide the norms for the test. WISC-III normed on Cdn samples (1,100).
Average range of scores by the standardization sample that all WISC scores are relative to. One norm for each age group. Raw scores become scaled btwn 1-19, with 10 being 50th percentile (mean, average). Average range is 7-13 (SD-3).
1 of 3 IQ scores. Derived from scores on 6 sub-tests (info, digit span, vocab, arithm, compr, similarities) Average IQ score-100, SD of 15. (Range:85-115) SEM of 4.
1 of 3 IQ scores. Derived from scores on 8 sub-tests (Mazes, Symbol Search, Object Assembly, Block Design, Picture Arrangement,Picture Completion, Coding) Average IQ 100, SD of 15. S.E.M. of 5.
Full Scale IQ
1 of 3 IQ scores. Derived out of scores on bother Verb & Perf IQs. When those two vary, Full scale IQ should be judged cautiously. (12 pt diff is significant) Average IQ score 100, SD of 15. S.E.M. of 3.5.
Standard Error of Measurement (SEM)
The error in IQ scores are known b/c tests have error. To compensate, there is a SEM..the range in which examiners are confident a ch's true IQ lies.
Bands of Errors
Specify ranges which we are confident the ch's IQ lies. SEM x2. (Ex: VIQ score +/- (SEMx2))(Ex: Joe VIQ is 105 +/- 8, or btwn 97-113)
Spatial Ability Score
A grouping of scores from sub-tests (Picture Completion, Block Design, Object Assembly) in order to better analyze performance instead of just based on IQ score. Cluster scores proposed by Bannantyne. Avg scale score 30.
A grouping of scores from sub-tests (Comprehension, Similarities, Vocabulary) in order to better analyze performance instead of just based on IQ score. Cluster scores proposed by Bannantyne. Avg scale score 30.
A grouping of scores from sub-tests (Digit Span, Picture Arrangement, Coding) in order to better analyze performance instead of just based on IQ score. Cluster scores proposed by Bannantyne. Avg scale score 30.
Verbal Comprehension Factor
Sub-factors used to interpret results of WISC sub-tests. (Info, Similarities, Compr, Vocab) Extended from Bannantyne's clusters.
Number Facility/Working Memory
"Factor 3". Sub-factors used to interpret results of WISC sub-tests. (Arithmetic, Digit Span) Extended from Bannantyne's clusters. Emotional state of ch. is a factor (ex: anxiety)
Perceptual Organization Factor
Sub-factors used to interpret results of WISC sub-tests. (Pic Completion, Pic Arrangement, Object Assembly, Block Design) Extended from Bannantyne's clusters.
Visual Motor Processing Speed
"Factor 4" Sub-factors used to interpret results of WISC sub-tests. (Coding, Symbol Search) Extended from Bannantyne's clusters.
WISC Factor Scores
The sum of the scaled scores in each factor group. Then normed based on a mean of 100. A result of Factor Analysis. 4 Factor groups - Verbal Comprehension, Perceptual Organization, Number Facility/Working Memory, Visual Motor Processing Speed.
The potential to acquire symbols, retain them, and to meaningfully communicate by means of those symbols. Could be verbal, non-verbal, spoken, written, objects, actions. Difficult for IQ tests to measure b/c of definition and factors like basic capacity & innate potential. Inferences about potential can be made based on performance on tests.