Personality psychology chapter3 insues in personality assessment

Types of Reliability• Internal reliability: reflects consistency within a set of items intended to measure the same construct • Test-retest reliability: reflects consistency of a measu

Chapter Three

Issues in Personality

Assessment

Issues in Personality

Assessment

Sources of Information

• Ratings by others

– Direct report by observer

– Peer ratings

• Self-reports

– Scales—assess a single aspect of personality – Inventories—measure several distinct aspects

of personality

Implicit Assessment

• Indirect means of determining what a

person is like

• Example: Implicit Association Test (IAT)

– People make categorical decisions rapidly

– Response times can reveal how closely linked different concepts are in a person’s mind

Types of Information

• Objective: measure of concrete reality that involves no interpretation

– Example—counts of the time a person touches another in an interpersonal interaction

• Subjective: measure that involves

interpretation

– Example—evaluation of facial expressions for signs of hostility

Consistency or repeatability of measurement

• High reliability = greater consistency =

lower randomness (error)

• Low reliability = less consistency = more error

Types of Reliability

• Internal reliability: reflects consistency

within a set of items intended to measure the same construct

• Test-retest reliability: reflects consistency

of a measure across time

• Types of Validity

– Construct

– Criterion

– Convergent

– Discriminant

– Face

Accuracy of measurement—does it measure what it’s supposed to measure?

Construct Validity

• Indicates a match between operational and conceptual definitions

• Most important type of validity

• Other types of validity help establish

construct validity

Criterion (Predictive) Validity

• Most important indicator of construct validity

• Examines how well a measure correlates with a standard of comparison (criterion)

– Example—does an aggression scale correlate with observer ratings of shoving on a playground?

• Examines how well a measure predicts an

appropriate outcome

– Example—does a self-esteem scale predict who will volunteer answers in class?

Convergent Validity

• Indicates appropriate correlation with

assessment devices presumed to measure the same construct

– Highly correlated

• Indicates appropriate correlation with

assessment devices presumed to measure

conceptually similar constructs

– Correlated, but not too high, not too low

Discriminant Validity

• Indicates that scale does NOT correlate with other assessment devices presumed

to measure conceptually dissimilar

constructs

Example: Correlations with Sociability scale

Number of friends 89 Convergent Validity

Hours spent alone -.92 Convergent Validity

Neuroticism 04 Discriminant Validity

Conscientiousness -.06 Discriminant Validity

Face Validity

• Indicates that the item or scale measures what you think it is supposed to measure

– Examples:

Construct Item

• Depression Do you often feel sad or blue?

• Optimism Do you generally expect good

things to happen?

Culture and Validity

• Important questions

– Does construct exist in all cultures? (cultural universality)

– Are items interpreted the same in each

culture?

Classic Representation of Reliability and Validity

Not Reliable

Not Valid

Reliable Not Valid

Reliable Valid

Challenges to Validity

• Memory bias

• Motivational bias

– Response sets—readiness to answer in a particular way

• Yea saying (acquiescence)

• Nay saying

• Social desirability

Two Approaches to the Development of

Assessment Devices

• Rational (Theoretical) Approach

– Start with conceptualization – Select items to fit conceptualization – Test validity and reliability

• Empirical (Data-Based) Approach

– Empirically driven from many items – Use statistical methods to select items based on ability of items to differentiate criterion group

Example of Empirical Approach

• Minnesota Multiphasic Personality

Inventory (MMPI)

– Started with many self-descriptive statements – Administered to “normals” and groups with psychiatric diagnoses

– Items selected for a scale were ones that

differentiated a particular psychiatric group from all others

When Are Different Methods Used?

• Rational Approach

– Usually in connection with theory building

• Empirical

– Usually used in connection with practical

needs

• Example: Vocational interests