Personality Assessment, Measurement and Research Design Chapter 2 Personality Assessment, Measurement and Research Design

How Important is Personality? https://www.google.com/search?biw=1278&bih=885&tbm=isch&sa=1&q=world+leaders+in+history&oq=world+leaders+in+history&gs_l=psy-ab.3..0j0i5i30k1l2.174558.177200.0.177963.11.11.0.0.0.0.178.1118.8j3.11.0....0...1.1.64.psy-ab..0.11.1102...0i67k1j0i30k1j0i8i30k1j0i10i24k1.aZEacG26DVE

Sources of Personality Data Self-Report Data (S-Data) Observer-Report Data (O-Data) Test-Data (T-Data) Life-Outcome Data (L-Data)

Self-Report Data (S-Data) Information a person reveals Limited by accuracy of information due to self-presentation and self-knowledge Individuals have access to a wealth of information about themselves that is inaccessible to anyone else

Self-Report Data Self-report can take a variety of forms Unstructured items—open-ended Structured items—response options provided

Self-Report Data Limitations of S-data People may not respond honestly People may lack accurate self-knowledge

Observer-Report Data (O-Data) Information provided by someone else (e.g. friends, family) about a person Advantages of O-data Provides access to information not attainable through other sources Multiple observers can be used to assess a person

Observer-Report Data Selection of Observers Professional personality assessors People who actually know the target person Often in better position to observe target’s natural behaviour than professional personality assessors Allows for assessment of multiple social personalities Because of relationship to target, however, observer may be biased

Observer-Report Data Naturalistic vs Artificial Observation Naturalistic observation: Observers witness and record events that occur in the normal course of the lives of the participants Artificial observation: Occurs in artificial settings or situations

Observer-Report Data Naturalistic observation has the advantage of being able to secure information in a realistic context, but at the cost of not being able to control events and behavioural samples witnessed Artificial observation has the advantage of controlling conditions and eliciting relevant behaviour, but at the cost of sacrificing realism of everyday life

Test-Data (T-Data) Information provided by standardized tests or testing situations The idea is to see if different people react differently to an identical situation Situation designed to elicit behaviours that serve as indicators of personality

Test-Data Limitations Participants might try to guess what trait is being measured and then alter their behaviour to create certain impressions Difficult to know if participants define testing situation as intended by the experimenter Researcher might influence how participants behave

Test-Data Can be designed to elicit behaviour that would be difficult to observe in everyday life Allow investigators to control the context and to eliminate extraneous sources of influence Enable experimenters to test specific hypotheses by exerting control over the variables that are presumed to have causal influence

Test-Data Mechanical recording devices, e.g. ‘Actigraph’ used to assess children’s activity Strengths Not hampered by biases of human observer May be used in naturalistic settings Disadvantage Few personality dispositions lend themselves to mechanical assessment

Test-Data Physiological data Include information about a person’s level of arousal, reactivity to stimuli—potential indicators of personality Functional magnetic resonance imaging (fMRI)—provides insight into the activity of different brain regions that can be linked with personality dispositions

Test-Data Physiological data Key benefit is that it is difficult to fake responses Disadvantages Often used in artificial laboratory setting

Test-Data Projective Techniques Person presented with a standard but ambiguous stimuli and asked to describe what he or she sees; assumption is that person ‘projects’ personality onto ambiguous stimuli

Projective Techniques

Test-Data Projective Techniques Strengths: May provide useful means for gathering information about wishes, desires, fantasies and conflicts that a person is not aware of and could not report Disadvantages: Difficult to score, uncertain validity and reliability

Life-Outcome Data (L-Data) Information that can be gleaned from events, activities and outcomes in a person’s life and which is available for public scrutiny, e.g. marriage, speeding tickets Can serve as important source of real-life information about personality but personality characteristics represent only one set of causes of life outcomes

Issues in Personality Assessment Links among different data sources Interpreting links between sources of personality data depends on the research question being posed Fallibility of personality measurement All sources of data have limitations Results that transcend data sources—’triangulation’—are most powerful

Issues in Personality Assessment Aggregation Adding up, averaging several observations can cancel out transient, momentary events Disadvantages include making questionnaires more tedious, discouraging participation

Evaluation of Personality Measures Reliability Validity Generalizability

Reliability Degree to which an obtained measure represents ‘true’ level of trait being measured Types of reliability Test-retest reliability Internal consistency reliability Inter-rater reliability

Response Sets Tendency of some people to respond to the questions on a basis that is unrelated to the question content (non-content responding) Acquiescence Extreme responding Social desirability

Validity Degree to which test measures what it claims to measure Types of validity Face validity Predictive or criterion validity Convergent validity Discriminant validity Construct validity

Generalizability Degree to which measure retains validity across different contexts, including different groups of people and different conditions Scales have high generalizability to the degree that they apply widely across different persons, situations, cultures and times

Development of Measurement Instruments Scale Development Conceptual definition is a must, followed by constructing items Test the items in focus groups Scale Diagnostics Investigate the reliability and validity of items using statistics

Research Designs in Personality Experimental Methods Correlational Studies Case Studies

Experimental Methods Used to determine causality—whether one variable causes another Two key requirements: Manipulation of variable(s) Ensuring that participants in each experimental condition are equivalent to each other at the beginning of the study

Correlational Studies Correlation is a statistical procedure for determining whether there is a relationship between two variables Designed to identify ‘what goes with what’ in nature Major advantage is that it allows us to identify relationships among variables as they occur naturally

Correlational Studies Correlation coefficient varies from –1 (perfect negative relationships) through 0 (no relationship) to +1 (perfect positive relationship) Correlation does not indicate causation Directionality problem Third variable problem

Case Studies In-depth examination of the life of one person Advantages Can find out about personality in great detail Can give insights into personality that can be used to formulate a more general theory that is tested on a larger sample Can provide in-depth knowledge about an outstanding figure

Case Studies A disadvantage is that results based on the study of a single person cannot be generalized to others Therefore, most often used as a source of hypotheses and as a means to illustrate a principle by bringing it to life

When to Use Experimental, Correlational and Case Study Designs Experiments—ideally suited for establishing causal relationships among variables Correlational designs—ideally suited for establishing the relationships between two or more variables occurring in everyday life Case studies—ideally suited for generating hypotheses that can be tested subsequently

Summary and Evaluation Four major sources of personality data (S-data, O-data, T-data and L-data) Decisions about data source and research design depend on the purpose of the investigation There are no perfect methods or designs But some data sources and some methods are better suited for some purposes than for others

Let’s Observe Personality https://www.youtube.com/watch?v=b9D6k3T2sbE

Critical Thinking Question #4 Pick two personality characteristics from this list: Openness; agreeableness Now, describe how you could measure this personality characteristic. You may use ANY technique described in the lecture – but you MUST be specific!