Trait Aspects of Personality II

3. Factor Analytic Approaches: Cattell, Eysenck, & Five-factor model

A. Factor Analysis: A way of finding traits -- see the separate handout.

B. Catell's Trait Approach

a. Personality - a compound made up of a limited number of universal elements; factor analysis can identify the universal traits that make up all individual personalities.

b. Source of data (three broad sources of data about personality)

* All three sources are required for any factor analysis that aims to uncover all the major dimensions of personality.

a) L-data (Life record data) : gathered from a person's life records (e.g., school records and world history) or ratings made by one person of another person in an every day situation

b) Q-data (Questionnaire data): gathered from questionnaires and interviews; individual answers direct questions about himself, based on personal observations and introspection (self-rating).

c) T-data (objective Test data): obtained from objective testing situations.; involves behavioral miniature situations in which the subject is unaware of the relationship between the response and the personality characteristic being measured. (fast tempo-measured by the arm-shoulder movement)

* According to Cattell, if factor-analytic research is able to determine the basic structures of personality, then the same factors or traits should be obtained from the three kinds of data.

c. Research with the L-data & Q-data

Started with a list of 18,000 words from dictionary

Reduced the list to 171 trait-elements by combining synonyms

Had people rate other people on these

Computed the intercorrelations among all the pairs of trait-elements.

Found 40 trait clusters (pairs) (called surface traits) that yielded a r above a certain criterion, e.g., .70

Computed the intercorrelations among the 40 surface traits and factor analyzed the resulting correlation matrix to discover source traits, the building blocks of personality.

Found 15 source traits. Universal traits because they are based on entire English words.

Developed the 16 P.F. questionnaire, which contains 12 traits that match traits found in the L-data research and 4 traits that appear to be unique to questionnaire methods.

The three most significant source traits are Introversion/Extroversion, Intelligence, and Ego Strength.

d. Surface Traits and Source Traits

a) Surface traits : clusters of overt or manifest trait elements (responses) that seem to go together.

b) Source traits : building blocks of personality;

Source traits are the underlying variables that are the causal entities determining the surface manifestations;

tend to be more stable than surface traits;

can only be discovered by factor analysis;

relative to surface traits, there are only a small number of source traits.

C. Eysenck's Type Approach

a. Basic dimension of personality: a smaller number of types. Types, like traits, tend to be normally distributed; that is , they are continuous dimensions and most people fall around the average mark.

b. Structural model: Types are at the top of the personality structure and, therefore, exert the most commanding influence. Types are composed of trait; traits are composed of habitual response. At the most specific level. specific responses are the elements from which individuals form habits.

c. He applied factor analysis to ratings and classifications of about 10,000 soldiers. Personality can be understood in terms of three basic personality factors: Introversion- Extroversion, Neuroticism (stable-unstable), and Psychoticism.

d. Extroversion and Neuroticism have received the greatest amount of attention by Eysenck. Both factors represent a continuous, normally distributed range between polar opposites, Each person can be positioned somewhere along the line between extreme introvert and extreme extrovert or between perfect emotional stability and complete emotional

e. Psychoticism

a) Psychoticismplays a somewhat smaller role than Extroversion and Neuroticism.

b) Psychoticism includes a disposition toward psychosis and a degree of psychopathy.

c) People who score high on Psychoticism are characterized by 11 dispositions (e.g., solitary, not caring for people; troublesome, not fitting in; cruel, inhumane; lacks feeling, insensitive; sensation seeking, aggressive etc.)

d) Psychoticism is higher in men than in women; heritable; higher in prisoners than in nonprisoners.

f. Biological bases of Extroversion and Neuroticism

a) Individuals high in Extroversion (extroverts)--having less-arousal cortexes and higher sensory thresholds; seeking stimulation to maintain their brain activity levels and avoid boredom; extreme introverts are so easily aroused that they shy away from stimulation.

b) Individuals high in Neuroticism--having more arousable autonomic nervous systems than more emotionally stable individuals; this biological reactivity lead to the psychological state of instability.

Experiments on Extraversion and Introversion.