3 different approaches to intelligence testing
- psychometric approach
- information and processing approach
- cognitive approach
The psychometric approach
- oldest approach
- concerned with the structure of the test and its correlations and underlying dimensions
Information processing approach
Concerned with the processes that underlie how we learn and solve problems
Cognitive approach
How we adapt to real-world demands
Common definitions of intelligence
- ability to adapt to new situations
- ability to learn new things
- ability to problem solve
- ability for abstraction (use of symbols and concepts)
historical beginnings of intelligence
1904 Binet
French government wanted ways to identify “subnormal” or “intellectually-limited children”
First had to define intelligence, then measure
Tripartite definition – intelligence is the capacity to:
1. Find or maintain a definite direction or purpose
2. Make necessary adaptation to reach that direction or purpose
3. Engage in self-criticism so that necessary strategic adjustments can be made
Binet’s contribution
- Age differentiation: older children have greater ability than younger, mental and actual age can be differentiated.
- general mental ability = total product of different & distinct elements of intelligence
- Intelligence can be represented by a single score
Intelligence according to Weschler
- intelligence has certain specific functions that are inter-related and each element contributes to general intelligence
- intelligence is related to separate abilities
Background to Weschler scales
Felt Binet scale was not appropriate for adults as Items selected for use with children not appropriate for adults
Emphasized role of non-intellective factors
- Reflected in the PIQ scale
- 1st to directly compare verbal and non-verbal intelligence
Thought mental age norms not apply to adults
Thought Binet did not take into account decline of performance with aging
Defining intelligence
Fluid intelligence
Crystalized intelligence
Verbal vs. performance IQ
Emotional, social, etc
Fluid intelligence
abilities that allow us to think, reason, problem solve and acquire new knowledge
Crystalised intelligence
the knowledge and understanding already acquired
Purpose of intelligence assessment for children
-school placements in cases of:
below average functioning
learning difficulties
management
Purpose of intelligence assessment for adults
- neuropsychological assessment
- forensic assessment
- disability grant
Vocabulary to test intelligence
- one of the most stable measures of intelligence
- often the last to be affected when deterioration occurs so useful for estimating premorbid ability
- list of words on stimuli card- give description and definition
using similarities to test intelligence
15 items of (supposedly) increasing difficulty
Become more & more abstract
In what way are a coat & a suit similar?
Both items of clothing
Vs. A coat you wear over your clothes and a suit you wear under your coat
Vs. They are not similar
arithmetic to test intelligence
Assesses:
- Concentration
- Motivation
- Memory
Most sensitive to MH/IH and educationally deprived individuals
Spatial aspect
Digit span to test intelligence
- digits forwards measures attention
- digits backwards measures working memory
- norms= 7 forwards, 5 backwards
information to test intelligence
E.g., Name two people who have been generals in the US army.
Abilities to comprehend instructions, follow directions and provide a response
Influenced by curiosity and interest in the acquisition of knowledge
comprehension to test intelligence
- 3 types of questions:
1. situational action (what to do in a given situation)
2. logical explanation
3. proverb definition
measures judgement in everyday situation
emotional disturbances influence performance the most
Letter-number sequencing to test intelligence
Additional test
Not required for calculating VIQ
Re-ordering numbers and letters
E.g., 1-A-5-C-9-B re-ordered to -5-9-A-B-C
Measures WM and attention
VIQ scoring
Raw score = total number of points
Raw scores then converted to scaled scores
With M = 10 and SD = 3
Done by comparing raw score to a table of norms
Raw scores not meaningful because:
Different subtests have different max scores
Same raw scores for people of different ages not comparable
2 types of norms in VIQ scoring
- age adjusted
2. reference groups (compare performance to performance of people in the standardized sample between ages 20-34)
Creating age-adjusted norms
Done by preparing a cumulative frequency distribution of raw scores for each group
Distribution then normalized
Appropriate scaled scores calculated against M = 10 and SD = 3
