What makes a theory good?• Comprehensiveness

– Bandwidth (Wide Range)– Fidelity (Very Specific)

• Parsimony (Ockham’s Razor)

• Research Relevance– Empirical Testability– Falsification must be possible

Personality Traits

Is our personality defined by a limited number of basic, universal

traits?

Overview

• What is a trait?

• What is the trait approach?

• How do traits measure personality?

• Famous trait theorists

• Criticism of the trait approach

Self-Descriptions (USA)• "I am a very independent, somewhat overbearing female

who is quick to speak her mind … I am sometimes stubborn, judgmental , and I have been known to forgive too easily, which makes me seem 'two faced' at times"

• "Easy-going, reflective, sarcastic sense of humor, loyal, caring, competitive, analytical, self-critical, compassionate"

• "I have a great tendency to be a perfectionist … I am a superstitious person … also, I am a completely honest person … I see myself as less of a speaker and more of a listener."

A Working Definition of Traits

• “Traits are many things to many people” (Wiggins, 1997)

• Global tendencies to think, feel, behave in a certain way

• Helpful in describing and comparing psychological attributes of people

• Related to laypeople’s views of personality

Main Assumptions

• Traits are stable over time

• Traits are stable across situations

• Traits are hierarchically organized

• Traits are dimensional - not categorical

• Individuals are unique in ...– how high they score on each trait– patterns of traits– number of traits (for some models)

Hierarchical OrganizationExample: Eysenck’s Description of Extraversion

S pe c ific Re s pons eA pproa ch ne ighbor

S pe c ific re s pons eA pproa ch C o-W ork e r

Ha bitua l Re s pons eA pproa ch People

Ha bitua l Re s pons eE ye conta c t

T ra itS oc ia lb i l i ty

T ra itA c tivi ty

T ra itS e nsa tion s e e k ing

D im e ns ionE x tra ve rs ion

Traits vs. Types• Types (e.g. body types)

– categorical– each person gets assigned to one type

• Traits (e.g. extraversion)– dimensional– quantitative value on a scale

Introverted Neutral Extraverted

|--------------------------|--------------------------|

Normal DistributionNum

ber of people with that value

Introverted --------------------------- Extraverted

Histogram of ExtraversionNum

ber of people with that value

Introverted --------------------------- Extraverted

0-20 20-40 40-60 60-80 80-100

Research Controversies

• Number of basic traits?

• Sources of traits (biological vs. learned)

• “Ontological” status of traits– Traits as “causes” of behavior – Traits as descriptions of behavioral tendencies

• Which research approach is best?

• Traits vs. states

Research Approaches• Nomothetic

– Limited number of universal traits

– Research on the distribution of universal traits in the population

• Idiographic

– Unique traits for specific individuals

– Intensive study of a few individuals

Refining Trait Measurement

Snyder (1974): Self-monitoring• High self-monitors adapt to the current situation• Low self-monitors have consistent traits

Bem & Allen (1974) “On predicting some of the people some of the time”

• People differ in their consistency for traits• Only personally relevant traits are consistent

Traits vs. StatesTrait• Enduring disposition• Stable across time and situations

State• Reaction tendencies, moods

• Dependent on the situation

Spielberger (1983) State-Trait-Anxiety-Inventory

Development of Personality Tests

How do we describe people?

Test ConstructionRational• Develop a theory about number & nature of traits• Formulate questions that describe each of the traits

Empirical• Collect large number of items• Pick the ones that differentiate between different

groups of people

Factor Analytic• Collect large number of items• Pick the ones that form well-defined clusters

Important Trait Theorists

• Allport (lexical studies)

• Eysenck (biological basis of traits)

• Goldberg, Costa, McCrae (“Big

Five”)

Allport (1897- 1967)

• Lexical studies (with Odbert, 1936)

• Extracted 17, 953 person-descriptive terms

• Traits as biological cause of behavioral trends in humans

• Idiographic approach

Eysenck (1916-1997)• Emphasis on objective scientific methods• Hierarchical view of personality traits• Three dimensions of personality:

– Introversion– Neuroticism– Psychoticism

• Traits are based on reactivity of the nervous system (introverts more reactive)

True or False?Compared to Introverts, Extraverts …

• have more positive emotions on average

• are physiologically more responsive to the same noise

• have earlier and more varied sexual contact

• get drunk more easily

• seek novelty and social interaction

• study in coffeehouses, not libraries

• have more dates

• have fewer but more intense friendships

• find it harder to study with music on

• report that their lives are more meaningful

Goldberg, Costa, McCrae

• “Big Five” Model

• O penness to experience

• C onscientiousness

• E xtraversion

• A greeableness

• N euroticism

• Currently the most researched model

Big Five• Lexical approach & factor analysis

• Strong links to biology assumed

• Intercultural comparisons find similar factorial structure

• Research findings:– O: positive outlook– C: planful problem solving– E: seeking social support– A: avoiding confrontation– N: avoidant coping