Intelligence, Aptitude and Personality: Theories and Assessment
Intelligence theories
Spearman's g and s factors; Thurstone's primary mental abilities; Gardner's multiple intelligences; Sternberg's triarchic theory (analytical, creative, practical); Cattell-Horn-Carroll fluid versus crystallised intelligence. Fluid declines with age; crystallised holds or grows. IQ is standardised with mean 100 and standard deviation 15 (for Wechsler scales). Know reliability (consistency) versus validity (measures what it claims), and types: test-retest, split-half, inter-rater.
Aptitude and assessment
Aptitude tests predict future performance; achievement tests measure past learning. Standardisation, norms, and cultural bias are key issues. Heritability estimates apply to populations, not individuals.
Personality theories
Trait theories: Allport (cardinal, central, secondary), Eysenck (extraversion, neuroticism, psychoticism), the Big Five (openness, conscientiousness, extraversion, agreeableness, neuroticism). Psychodynamic (Freud: id, ego, superego; psychosexual stages), humanistic (Rogers, Maslow), social-cognitive (Bandura, Rotter's locus of control), and projective versus objective assessment (Rorschach, TAT versus MMPI, 16PF).
Traps and rule of thumb
Questions often confuse reliability with validity: a test can be reliable but invalid. Another trap is treating heritability as applying to an individual. Rule of thumb: reliability is consistency; validity is accuracy. For IQ, remember 68-95-99.7 percentages for standard deviations.