Week 4 stability of personality

Question 1

Is personality fixed?:

Answer 1

® William James – character has set like plaster by the age of 30.
® Mischel et al. (1972, 2011) had 4-year old participants run through a delay of gratification protocol. How long the children waited before they ate the marshmallows predicted life outcomes including SAT scores, coping skills, aggression, educational achievement, drug use & health.
® McAdams & Olson (2010) found that temper tantrum frequency in early childhood predicts occupational instability. Inhibited 3-year olds tend to have low positive emotionality, social potency & wellbeing at 26. 3rd grade aggressiveness was also found to predict adult criminality

Question 2

Different type of stability

Answer 2

® Rank-order stability – the degree to which the relative ordering (position) of individuals on a given trait is maintained over time.
® Mean-level stability –consistency in the average level of traits over time.
® Individual stability – absolute consistency at the level of the individual person

Question 3

Rank-order stability result Costa & McCrae 1994

Answer 3

AKA test-retest reliability
Costa & McCrae (1994)
§Test-retest correlations ~ 0.65 for the B5 traits over multiple studies (up to 30-year periods)
§Indicates that, if one is above average on a trait at age 30, there’s an 83% chance (5:1 odds) they will be above average at age 50

Question 4

Rank order stability Damian et al. (2019):

Answer 4

Damian et al. (2019):
§1, 795 US residents
§Test-retest correlations ~ 0.30 for the big five
Rank-order stability …
1. Is relatively high (r > .30)
2. Increases over the lifespan (from ~ 0.41 in childhood to ~ 0.55 at age 30, to ~ 0.70 at age 60).
3. Decreases as the test-retest interval increases (>.60 over a 1-year period, ~.30 over a 40-year period)
4. Is trait general, i.e., does not vary across:
- Big Five traits
- Assessment method (e.g., self-reports, observer ratings)
- Gender

Question 5

What influences rank-order stability?

Answer 5

Genetic influences •Probabilistic influences of genes on behaviour/experience
Environmental channeling
•Our environments stabilize over time
•‘Settling down’, consolidation of habits, routines, friendships, etc.
Environmental selection
•We seek environments that match, support, and maintain our traits
•Moving or migrating to places that fit our values, preferences, habits etc.

Question 6

The evidence for Genetics influence on rank-order stability

Answer 6

•Longitudinal twin study used to estimate the influence of genetic vs. environmental influences on stability:
•79 MZ twins, 48 DZ twins, studied from age 20 to age 30.
•70-90% of stability owing to genetic factors
•70% of change owing to environmental factors
-Genetic relatedness accounted for a large part of the test-retest reliability
-Genetic relatedness accounted for a small part of the unpredicted variance

Question 7

Influences on rank-order stability: Environmental channelling exp

Answer 7

Caspi & Herbener (1990)
•126 continuously married couples given personality assessments in 1970 and 1981
•Rank order stability was higher for couples with more similar personalities

Question 8

Influences on rank-order stability
Environmental selection prove

Answer 8

Evidence that personality influences environment selection…
•Assortive mating (“Birds of a feather flock together”):
•Trait correlations between romantic partners and friends, up to r = .35
•Migration:
•Personality predicts movement between cities/countries
•Vocational choice:
•Personality predicts choice of major and vocational choice
…but little evidence that environmental transitions impact personality stability
•Test-retest stability similar throughout migration vs non-migration

Question 9

Mean-level personality change studies Costa & McCrae (1994)

Answer 9

Costa & McCrae (1994)
•O, E & N drop over adulthood
•A and C rise over adulthood
•Suggests a general tendency for people to become nicer, more responsible, more set in their ways, less gregarious, and to experience less negative emotions…

Question 10

Mean-level personality change studies Robins & Mroczek (2009): university student

Answer 10

•Longitudinal study of young adults (university students, age 18 to 22)….
•A and C rose
•O and N fell
•E remained stable

Question 11

Mean-level personality change Bleidorn et al. (2009) studies on university students

Answer 11

•10-year study of adults aged 18-59…
•A and C rose
•O and N fell
•No change for E, but diverging patterns at the facet level…
•Assertiveness increased
•Gregarious and excitement-seeking degreased

Question 12

Conclusion from mean level personality changes trajectory

Answer 12

•Mean-level change seems to be broadly positive, toward “Psychosocial Maturity”
•Patterns of mean-level personality change are…
•Conceptually similar to classical psychological theories of maturity, e.g., involving engagement with the world (E, and C), forming and nurturing social bonds (A), and maintaining emotional security (N) (Allport, 1961)
•“Adaptive”, or linked with positive outcomes, such as wellbeing, career success, and health [more next week]
•Desirable, or positively evaluated (e.g., personality change goals)
•Thus, “personality development and maturation”

Question 13

Proposed explaination for mean level changes trajectory

Answer 13

•Genetic influences
•Evolved ‘maturation processes’
•“Developmental tasks”
•E and O more helpful around reproductive age
•C more helpful during parenting
•Environmental effects•Major life transitions / stages / role shifts
•Independence from parents, parenthood, etc.

Question 14

The evidence: for genetic influence in mean-level change

Answer 14

Loehlin (1993)
•Personality change scores correlated .50 for MZ twins, .18 DZ twins
•Genetic ‘switches’ may be partially responsible for systematic patterns of change
•However, Hopwood et al., (2011):
•624 twin pairs assessed 3x over 12 years (late teens –late 20s)
•For conscientiousness: genetic effect > environment effect
•For neuroticism: only a significant environment effect
•(Minimal change observed for other traits)

Question 15

Sources of mean-level change for enviromental influences: cross cutural changes

Answer 15

Cross-cultural comparisons:
•If environments drive mean-level change, then change patterns should vary across different environments
McCrae et al. 1999:
•Examined age-personality relations in 7,363 persons from Germany, Italy, Portugal, Croatia, South Korea
•Personality differences generally matched patterns of mean level change in the US…
•Age related differences in E, A, O, and C very similar across counties
•Pattern for N similar only in Germany, South Korea, and the US.

Question 16

Sources of mean-level change of japan and US
Chopik & Kitayama, 2018:

Answer 16

•9-year study of mean-level change in the US (N = 6,259) and Japan (N = 1,021)
•Changes in A, O, E, and N were similar between countries
•For C, contrasting trajectories…
ØPeak in US conscientiousness earlier compared to Japan

Question 17

Sources of mean-level change in cross culture studies
Terracciano, 2015:

Answer 17

•Review of cross cultural studies of mean-level change
•Studies spanned a wide range of cultures/nations (from all continents), incl. one study comparing 62 nations.
•Overall picture:
•“the pattern of [mean-level] personality development is remarkably similar across cultures.”
•Suggests cross-cultural generality of mean-level personality change

Question 18

Sources of mean-level change in chimps
King, Weiss, & Sisco, 2008:

Answer 18

•Mean-level personality change in Chimpanzees…
•N = 202 Chimpanzees in US zoos
•Results
•O, E & N drop over the lifespan
•A rises
•C rose (but not significantly)
•Similar patterns to humans – suggests cross-species generality of mean-level personality change
•Evolved ‘maturation processes’?

Question 19

Sources of mean-level change
Environmental influences…
Major life transitions — transition to work

Answer 19

Roberts, 1997:
•~100 women followed up for ~20 years (early 20s-40s), from late 1950s-1980s
•Greater participation in the workforce associated with increases in ‘agency’ (part of E)
•Potentially contributes toward typical mean level changes?
•But this could also be an environmental selection effect…

Question 20

Sources of mean-level change
Major life transitions—transition to parenthood

Answer 20

Avison & Furnham, 2015:
•Adults with (or desiring) children vs. voluntarily childless adults:
•Higher in E, A, and lower in O
•But this could also be an environmental selection effect…
Sheppington et al., 2017—longitudinal study:
•2,469 adults aged 17-45 with no children in 2005 followed up in 2009
•556 had their first child between 2005 and 2009
•No significant mean-level change in parents vs non-parents
•Evidence for environmental selection:
•Those who had children were higher in E and lower in O at baseline

Question 21

Sources of mean-level change
Cohort effects?

Answer 21

•Is personality influenced by broad historical / societal shifts?
•e.g., exposure to war or adversity, or changes in technology?
àJean Twenge’s ‘generation me’
•Claim:
•American Gen Xs (born 60s-80s) and millennials (80s-90s) have inflated self-esteem, egotism, and expectations of the future
•Explanation: •Relative affluence and “culture of self worth” throughout the 1970s-1990s

Question 22

Criticisms of Twenge’s studies on cohort effect

Answer 22

•Sampling issues (not representative) from mainly university students
•Over-estimation of effect sizes (individual vs aggregated scores)

Question 23

Futher test for cohort effect in US

Answer 23

Large-scale test of ‘generation me’…
•~500,000 US high school students sampled from 1970-2006
•Completed various psychological and personality assessments
Results:
•No evidence for inflations in self-esteem / egotism
•Moderate increases in educational aspirations, and decreases in concerns about social problems (rs~.20)
•All other trends were very small (rs~.10)
•Conclusion: Minimal support for any marked generational
change during this period

Question 24

Further test for cohort effect in New zealand

Answer 24

•Focus was on ‘entitlement’ (e.g., “I feel entitled to more of everything”)
•Representative NZ sample (N = 10,412)
•Compared both age-related trends (from age 19-74) and mean-level change (from 2009 to 2014)
Results:
•Negative relationship between entitlement and age
•Increases in agreeableness?
•But no increases in entitlement among younger participants
•Similar findings in Canada and Australia (Hamamura et al., 2020)
•Conclusion: Again, minimal support for ‘Generation Me’.

Question 25

Overall Picture of source for mean level changes

Answer 25

Genetic influences:
•At least some evidence for genetic contributions to mean-level change
•Patterns observed in US/Western samples show at least some degree of cross-cultural generalisability
•Some evidence for cross-species generalisability
•Suggestive of universal/evolved maturation patterns
Environmental influences:
•Difficult disentangling environmental effects on mean-level change from personality effects on environmental selection
•Limited support for hypothesised cohort effects

Question 26

Beliefs about personality change

Answer 26

Haslam et al. (2007)Beliefs about normative mean-level personality change through the lifespan are reasonably accurate
People believe that personality changes less with age—as is the case for rank-order stability…

Question 27

Studies on beliefs about personality changes

Answer 27

Quoidbach et al., 2013 (studies 1-3):
•7,519 adults aged 18-68
•First, completed a brief personality inventory
•Then assigned to 1 of 2 conditions
•Reporter: complete for yourself 10 years ago
•Predictor: complete for yourself in 10 years time
•Computed average of absolute difference in all big five trait
scores to index predicted change and reported
® People reported a larger degree of personality change than they were predicting for themselves change…

Question 28

Quoidbach et al., 2013 (study 2):

Answer 28

•Contrasted the remembered and predicted changes in personality to actual changes in personality in a separate longitudinal sample
•Actual personality change was virtually identical to the magnitude of reported change in the ‘reporter’ condition,
•but substantially larger than the magnitude of predicted change in the ‘predictor’ condition.

Question 29

Quoidbach et al., 2013 (study 4):

Answer 29

•170 participants adults, average age = 34 years
•Then assigned to 1 of 2 conditions
•Past concert: How much would you pay now to see your favourite musician/group from 10 years ago this week
•Future concert: How much would you pay now to see your current favourite in 10 years
•Past concert participants willing to pay $80, but future
concert participants willing to pay $129

Question 30

indiviadual changes

Answer 30

•Individual differences in personality change (Roberts & Mrozek, 2008)
•The Big Five change in ways that vary across individuals in the direction and rate of change.
- Occur due to uniqueness of experiances

Question 31

important practical implications of individual changes

Answer 31

Health
•Conscientiousness predicts health, and changes in conscientiousness predict changes in health
•12-year longitudinal study of ageing men (age 43-91):
•Neuroticism predicts mortality
•Changes in neuroticism predict mortality, with high and increasing neuroticism predicting an earlier death

Question 32

Example of Individual Change

Answer 32

Transition to work (again):
•People often have different experiences during these transitions
Roberts et al., 2003
•~1,000 young adults followed up for ~10 years
•Personality predicted positive work experiences (occupational attainment and financial security)
•But, positive work experiences also predicted changes in personality (increased E, decreased N)

Question 33

Individual Change
Effects of travel / temporary migration study

Answer 33

•University students on ‘study abroad’ for 1 or 2 semesters (N = 527) vs control students (N = 607)
•Selection effects:
•Abroad for 6 months: higher E and C
•Abroad for 1 year: higher E and O
•Effects of travel:
•Increases in O and A
•Decreases in N

Question 34

Individual Change due to Travel..

Answer 34

•Additional observations
•C àshort term travel (reflects cv building?)
•O àlong term travel (seeking greater immersion?)
•For O and N, personality change was mediated by increases in ‘relationship gains’

Question 35

Individual Change Impact of clinical interventions:

Answer 35

•Meta-analysis of 207 studies:
•Lasting changes, especially for decreased neuroticism, and (to a lesser extent) increased extraversion
•Magnitude of change similar across therapy type (e.g., pharmacological, cognitive behavioural, etc.)
•Non-linear impact of therapy duration:
•<1 month: minimal effects
•Dose-dependent effect up until ~8 months
•Greater effects for some presenting problems than others (e.g., anxiety vs. substance use)

Question 36

Can we choose to change

Answer 36

•Little (2000):
•‘Free traits’ and ‘Personal Projects’
•From acting ‘out of character’, to resolving to become more social/kind/disciplined etc
•Fleeson (2001): Personality traits vs states:
•Acting temporarily more extraverted or conscientious than we normally are
•Are we motivated to act counter dispositionally?

Question 37

Acting extraverted for goal pirsuit

Answer 37

•10-day Experience sampling study…
•Momentary goals accounted for most of the within-person variance in state extraversion :
•e.g., to attract attention; engage in leadership; make a positive impression; form friendships; have fun

Question 38

Acting conscientiousness

Answer 38

•10-day experience sampling study + 2 experiments …
•Momentary goals also accounted for most of the within-person variance in state conscientiousness :
•e.g., to use time effectively, to get things done, to direct energy where needed

Question 39

Volitional Personality Change?Hudson & Fraley, 2015 :

Answer 39

•Study 1: 135 students over 16 weeks
•Study 2: 151 students over 16 weeks
•Research Questions:
1. Do people want to change?
2. Do people change as desired?
3. How do they change?

Question 40

Hudson & Fraley, 2015 : Do people want to change

Answer 40

Yes:
•Previous research suggests ~90% of people want to change their personality in some way
•In both studies people desired, on average increased E, O, A, C and decreased N
•Speaks to ‘psychosocial maturity’

Question 41

Hudson & Fraley, 2015 Do people change as desired?

Answer 41

Yes:
•In both studies: Increased E, O, A, C and decreased N over time
•Was the change large?
•.02 standard deviations per month (averaged across traits/studies)
•Small… but equates to > 4 SDs over 20 years!

Question 42

Hudson & Fraley, 2015 How did they change?

Answer 42

Via counter-dispositional behaviour: (acting out)
•Goals lead to change in personality states which change in traits
•For E, A and N only
But also via ‘identity’:
•Goals àchange in traits àpersonality states
•For E, C and N only