CLASS 10

Trait Theories

Recall the three definitions of personality

• lay definition: friendly, interesting, etc.

• grand theory of psychology (e.g. Freud)

• individual differences in social behavior– i.e. traits

Personality Traits

• predispositions to respond consistently across time and situations

• e.g., sociable, dependable, cruel

• NOT values, intelligence, moods

3 modes of measurement

1. Self-rating

2. Observer rating

3. Behavior

• Convergence is most convincing

A: Too many to study

Okay, but how many?A: Dictionary has 4,500 traits

– 1 of every 10 common English words

Q: How many traits are there?

• Cattell reduced them down to 1610 (e.g., by deleting evaluative words)

• Still too many

• so he applied Factor Analysis using a computer

We need a more manageable number

Factor Analysis (FA)

• Definition: A mathematical procedure that simplifies the correlations among a large number of traits.

• Slow and difficult to calculate by hand BUT

• In 1950s, modern computers became available

Let’s review the correlation coefficient (r)

• It indicates the size of association between 2 traits (e.g., talkative & anxious)

• Range of r: -1.00 to +1.00• r = +1.00 means perfect match• r = -1.00 means perfect reverse• R = .00 means no association

Typical personality study

• Administer a questionnaire to a large sample of people

• Ask them to rate themselves on a list of traits

• Calculate the correlation of each pair of traits

Correlation Matrix of 4 traits

excitable sociable reliable neat

excitable 1.00 .65 .03 .07

sociable 1.00 .00 .05

reliable 1.00 .73

neat 1.00

By eye-ball, we can see 2 factors

excitable sociable reliable neat

excitable -- .65

sociable --

reliable -- .73

neat --

Factor analysis by eyeball vs. computer

• Both start with a correlation matrix • Using the eyeball method revealed 2

factors: – F1 includes excitable and sociable– F2 includes reliable and neat

• But we need a computer to handle a matrix that is 1610 x 1610

Summary of steps in a factor analysis

• Collect a sample of self-ratings • e.g. 150 students rate themselves on 4 traits• Calculate all possiblecorrelations = 6• Calculate the number of factors in the

correlation matrix (the math part)• Find the right name for the set of traits in in

factor (the literary part)

Cattell’s conclusion in 1963

• 1610 traits can be reduced to

• 16 factors of personality

• e.g., outgoing, calm, dominant, etc.

Can we reduce them further?

• YES• His factors were correlated with each other• i.e., they overlapped too much• How many distinct dimensions of

personality are there?

• Answer from Goldberg (1980): FIVE

The BIG FIVE dimensions Extraversion

Agreeableness

Conscientiousness

Neuroticism

Openness

The OCEAN of personality

Extraverted (vs. introverted)

• Talkative, Sociable, Fun-loving, Energetic

• e.g., • Jim Carrey

Theory: Need for excitement

Agreeable (vs. argumentative)

• Sympathetic, Warm, Trusting, Cooperative

e.g., Marge Simpson

Theory: • Need for harmony

Conscientious

• Dependable• Productive• Neat

Theory: • Sense of duty

vs. lazy

Neurotic (vs. stable)

• Anxious, Insecure, Guilt-prone, Self-conscious

e.g., Woody Allen

• Theory:

– Sensitive to punishments, failures

Open to Experience (vs. practical)• e.g., Lady Gaga• Many interests, especially creative ones• Prefers ideas over practical issues• Politically liberal

• Theory:• anti-conformist

The Big Five are independent dimensions

• Five separate pieces of information

• Uncorrelated, independent, orthogonal

• all 32 combinations are equally likely

SCORE YOURSELF

• See link on course web site

• Brief 10-item scale

• Norms from 1813 college students

Why do these five show upin factor analyses?

• Importance?

• Salience?

• Accident of language history?

Critique:

• Too static

• Implies rigidity

• No overall theory