1 Psychology 305A: Personality Psychology January 14 Lecture 3

2 Announcement The tutorials for the Peer Mentor Program will be held on the following dates: January 21, 3:30-4:30 February 12, 3:00-4:00 March 4, 3:30-4:30 March 24, 4:00-5:00 April 7, 4:00-5:00 Location to be announced.

A little R&R …. (Review and Reflect) 3

Psychology 3054 Personality Assessment and the Trait Perspective 1.How are personality variables measured? 2.How do researchers establish the reliability and validity of a personality measure? 3.What are traits? 4.Has a comprehensive taxonomy of personality traits been developed? 4

By the end of today’s class, you should be able to: 3.distinguish between face, predictive, convergent, and discriminant validity distinguish between internal consistency, inter-rater reliability, and test-retest reliability. 1. review personality measurement techniques. 4. describe Eysenck’s personality taxonomy.

How are personality variables measured? (continued) 6

Psychology 3057 Participants complete the statement “I am” 20 times. Researchers count the number of statements that refer to a given personality characteristic. Unstructured Self-Report: The Twenty-Statements Test I am _______________ I am _______________ 7

Psychology 3058 True/false items: I like loud and crowded parties ………… T/F I enjoy trying new foods …………………. T/F Adjective checklists: adventurous conservative Structured Self-Report: True/False Items and Adjective Checklists 8

9 Using the scale below, please indicate how much you disagree or agree with the following statements. Circle the appropriate number to the right of each statement StronglyNeutralStrongly disagree agree 1. I feel that I’m a person of worth, at least on an equal basis with others …………………………… I feel that I have a number of good qualities …… All in all, I am inclined to feel that I am a failure … I am able to do things as well as most people ……12 9 Structured Self-Report: Rosenberg’s Self-Esteem Scale

10 Rosenberg’s Self-Esteem Scale:  Measures global feelings of self-worth (“trait” self- esteem).  Mean score for university undergraduates: 38 (maximum possible score = 50), SD = 6.2.  Females tend to score slightly lower than males, largest sex difference in adolescence (15-18). 10

11 How do researchers establish the reliability and validity of a personality measure? In order to accurately assess a personality variable, the measure that is used must be reliable and valid.  The consistency with which a measure assesses a construct across repeated measurements. Reliability 11

12  Three forms: 1.Internal consistency: Relevant for multi-item measures (e.g., questionnaires). The degree to which the items in the measure produce similar responses (i.e., tap the same construct). 12

13 Using the scale below, please indicate how much you disagree or agree with the following statements. Circle the appropriate number to the right of each statement StronglyNeutralStrongly disagree agree 1. I feel that I’m a person of worth, at least on an equal basis with others …………………………… I feel that I have a number of good qualities …… All in all, I am inclined to feel that I am a failure … I am able to do things as well as most people ……12 13 Structured Self-Report: Rosenberg’s Self-Esteem Scale

14 2.Inter-rater reliability: Relevant when observer ratings are obtained from two or more observers. 14 The degree to which the scores provided by different observers are consistent with one another (i.e., there is consensus among observers). Involves calculating the correlation between the scores provided by different observers.

15 3.Test-retest reliability: Relevant for all types of measures. The degree to which participants’ scores on the measure at time 1 are consistent with their scores on the measure at time 2. Involves calculating the correlation between participants’ scores on successive test administrations (i.e., their scores at time 1 and scores at time 2). 15

16  The degree to which a measure assesses the construct it is intended to measure. Validity (or construct validity)  A measure that is reliable may or may not be valid; a valid measure must be reliable. 16

17  Four forms: 1. Face validity: The degree to which a measure appears to tap the construct under study. E.g., Rosenberg’s Self-Esteem Scale. All in all, I am inclined to feel that I am a failure On the whole, I am satisfied with myself 17

18 2. Criterion validity (or predictive validity): The degree to which a measure correlates with a behaviour that is theoretically related to the construct under study. E.g., A self-esteem measure should be correlated with:  alcohol and drug use  persistence in the face of failure  number of sexual partners (i.e., sexual promiscuity) 18

19 3. Convergent validity: The degree to which a measure correlates with measures that assess conceptually-related constructs (i.e., constructs that are theoretically related to the construct of interest). E.g., A self-esteem measure should be correlated with measures of:  depression.  neuroticism.  positive affectivity. 19

20 4. Discriminant validity: The degree to which a measure does not correlate with measures that assess conceptually unrelated constructs (i.e., constructs that are not theoretically related to the construct of interest). E.g., A self-esteem should not be correlated with measures of:  agreeableness.  need for cognition.  political attitudes (i.e., liberal vs. conservative). 20

21 Often, convergent and discriminant validity are examined simultaneously: DepNeurPosAffAgreeNCognPolatt SE

Psychology According to the trait perspective, personality is best described as a constellation of traits (e.g., anxious, conscientious, outgoing). Example: Peter is jealous. “Jealous” describes Peter’s behaviour. Traits are viewed as descriptive summaries of behaviour. What are traits? 22

Psychology Has a comprehensive taxonomy of personality traits been developed? Taxonomy: A classification system (e.g., Periodic Table of Elements). 23 Over the past century, dozens of taxonomies have been proposed for personality traits. Examples:

1. Eysenck’s personality taxonomy: PEN Developed on the basis of pre-existing theory: Body Humors Theory (Hippocrates, Galen). Proposes three personality dimensions: Extraversion, neuroticism, and psychoticism. 24

Psychology Personality Types Derived from Eysenck’s Taxonomy Low Neuroticism (Emotionally Stable) High Neuroticism Emotionally Unstable Introvert Passive Careful Thoughtful A Peaceful Controlled Reliable Quiet Pessimistic Unsociable B Sober Rigid Moody Extravert Sociable Outgoing Talkative C Responsive Easygoing Lively Active Optimistic Impulsive D Changeable Excitable Aggressive A = Phlegmatic; B = Melancholic; C = Sanguine; D = Choleric 25

By the end of today’s class, you should be able to: 3.distinguish between face, predictive, convergent, and discriminant validity distinguish between internal consistency, inter-rater reliability, and test-retest reliability. 1. review personality measurement techniques. 4. describe Eysenck’s personality taxonomy.