CH 9 Basic Psy PP(1)
Module 9.1: Intelligence and Intelligence Tests
Learning Objectives:
Describe the g factor and its evidence.
Distinguish between fluid and crystallized intelligence.
Outline three common IQ tests.
Evaluate hereditary and environmental influences on intelligence.
Defining Intelligence
Intelligence lacks a precise definition.
Psychological assessments aim to quantify intelligence to gather insights.
The g Factor
Spearman's concept of g (general intelligence):
Represents an overlap among various intelligent abilities.
Each ability is influenced by specific factors (s).
Explanations for g
Potential underpinnings of g include:
Correlation between different intelligences linked by growth factors.
Links to mental speed or working memory.
Types of Intelligence
Fluid Intelligence: Ability to reason and solve new problems.
Crystallized Intelligence: Knowledge acquired and applied in contexts.
Gardner’s Theory
Proposes multiple intelligences:
Includes mathematical, artistic, muscle, and musical skills.
IQ Tests Overview
Aptitude: Learning potential (fluid intelligence).
Achievement: Knowledge acquired (crystallized intelligence).
IQ Tests: Predictions of performance in academic settings.
First developed by Binet and Simon.
Most common: Stanford-Binet and Wechsler tests.
The Stanford-Binet Test
Administered based on age; designed to assess various skills.
Adaptive testing adjusts item difficulty based on responses.
Provides visual reasoning, short-term memory, and IQ scores.
Examples of Stanford-Binet Test Items
Sample items across different ages to measure various cognitive skills.
The Wechsler Tests
WAIS–IV: For adults.
WISC–V: For children up to 16; includes overall IQ, verbal IQ, and performance IQ.
Used to identify strengths, weaknesses, and learning disabilities.
Culture-Reduced Testing
Progressive Matrices: Test of abstract reasoning without language barriers.
Fairer for non-native speakers, but offers limited strength analysis.
Genetic and Environmental Influences on IQ
Genetic correlation in intellect (
Monozygotic twins show high correlation).
Numerous genes have minor intelligence contributions; also influenced by epigenetics.
Environmental Influences
Intellectual growth depends on a healthy environment.
Early and sustained interventions can enhance cognitive development.
Module 9.2: Evaluation of Intelligence Tests
Learning Objectives:
Define test standardization.
Explain the Flynn effect.
Assess test reliability and validity.
Explore test bias and stereotype threat.
Standardization of IQ Tests
Standardization: Process for evaluating test items and interpreting scores.
Norms describe score frequency in populations.
Distribution of IQ Scores
IQ mean is 100, with a standard deviation of 15-16.
The mode often exceeds 100; some lower performance bulges exist.
The Flynn Effect
Improvement in IQ test scores across generations.
Average increase of about three points per decade; causes unknown.
Test Reliability
Reliability: Consistency of test scores over repetitions.
Test-retest reliability assesses score consistency over time.
Validity
Validity: Evidence supporting test score interpretations.
Evaluated through multiple evidence types (content, structure, outcomes).
Score Fluctuations
Less reliability leads to more score variability, especially in infants.
Test Bias
Bias: Overstatement or understatement of true performance in a group.
Efforts to remove biased items and ensure fair predictions for all groups.
Stereotype Threat
Stereotype threat: Fear of reinforcing negative stereotypes during performance.
Remedies include awareness of stereotype threat and supportive interventions.