How can we answer questions about personality scientifically? Personality Research Methods

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How can we answer questions about personality
scientifically?Personality ResearchMethods
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Self-Identification Survey
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Personality Research Methods

• Goals
• Most generally, to become more sophisticated
  consumers of research information
• To understand how we study personality
  empirically
• To appreciate strengths and weaknesses of various
  designs and analyses what they can and cant
  tell us about personality
• Be able to interpret some key types of statistics

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Personality Research Methods

• What is the purpose of research?
• To, as objectively as possible
• Evaluate theories
• Answer practical questions
• In general, to accumulate knowledge in an
  objective and public manner

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Personality Research Methods

• Three topics
• Research design
• Interpreting data (statistics)
• Measurement (personality assessment, already
  covered)

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Personality Research MethodsResearch Design

• Two broad kinds of questions in research
• 1) Is X related to Y?
• Are SAT scores related to GPA scores?
• Is emotional expressivity related to physical
  health?
• 2) Does X cause Y?
• Does medication cause symptom reduction?
• Does child abuse cause Borderline PD?
• Do genes determine sexual orientation?
• Causality is the big question

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Personality Research MethodsResearch Designs

• Types of research design
• Experimental
• Passive
• Case Study

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Personality Research MethodsResearch Design

• Experimental Design
• Manipulate a variable (IV) and measure changes in
  another variable (DV).
• Random assignment to conditions (levels of IV).
• Strengths and Limitations - Discuss

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Personality Research MethodsResearch Design

• Passive Designs
• Observe (measure) how pre-existing differences
  between people on one variable are related to
  differences between those people on another
  variable
• E.g., drug abuse and psychological adjustment
• Why Passive?
• Strengths and Limitations discuss

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Personality Research MethodsResearch Design

• Case Studies
• In depth analysis of specific entities (a person,
  a group, an organization)
• Eg, Charles Whitman Freud - the case of Little
  Hans Allport Letters From Jenny
• Strengths and limitations - discuss

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Personality Research MethodsResearch Design

• Personality Psychology often uses Passive Designs
• Why?
• Is Extraversion related to popularity?
• Is Drug Abuse related to psychological
  adjustment?

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Personality Research Methods

• Three topics
• Research design
• Interpreting data (statistics)
• Measurement (personality assessment, already
  covered)

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Personality Research MethodsInterpreting Data

• Statistics are nothing but tools to help us make
  sense out of data.
• We will typically
• Look for group differences on some variable
• Look for relationships among variables
• At one level, these are the same things.

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Your BFI Data

• A few questions to answer
• Is personality related to happiness?
• Are there sex differences in personality?
• Is personality related to GPA?
• Do these associations/differences differ by
  trait?
• But first how do we quantify/describe
  associations/differences?

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Personality Research MethodsInterpreting Data

• Why worry about this?
• General sophistication in critical thinking?
• Ability to understand studies that well be
  discussing
• Two general kinds of statistics
• Descriptive Statistics
• Inferential Statistics

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Personality Research MethodsInterpreting Data

• Two general kinds of statistics
• Descriptive Statistics
• To summarize/describe the data that was collected
  in a sample of subjects.
• Examples frequencies, means, standard
  deviations, correlation

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Personality Research MethodsInterpreting Data

• Two General Kinds of statistics (continued)
• Inferential Statistics
• To make statements/inferences about the
  population(s) of people from which the sample of
  subjects was drawn.
• Statistical significance. Is the result
  representative of the population?
• Male and female samples (20 each) find
  difference in IQ. Is this representative of the
  population of males and females?

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Personality Research MethodsInterpreting Data

• What is a correlation?
• A correlation (r) is a number that summarizes the
  direction and degree of association between two
  variables
• Do people who have high SAT scores also get
  relatively high GPAs?
• This is a question about the association between
  two variables SAT score and GPA.

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Personality Research MethodsInterpreting Data

• A correlation gives two pieces of info
• Direction of association
• people who score relatively high on one
  variable tend to score relatively high on the
  other
• - people who score relatively high on one
  variable tend to score relatively low on the
  other
• 0 there is no relationship between the variables
  - people who score relatively high on one
  variable are likely to score either high OR low
  on the other.
• Note relatively positive ? good

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Your BFI Data

• A few questions to answer
• Is personality related to happiness?
• Are there sex differences in personality?
• Is personality related to GPA?
• Do these associations/differences differ by
  trait?
• But first how do we quantify/describe
  associations/differences?

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Personality Research MethodsInterpreting Data

• A correlation gives two pieces of info
• Degree of association
• How strongly related are the two variables?
• Range from 1 (Very strong positive relationship)
  to 1 (Very strong negative relationship)
• Values closer to zero represent weaker
  relationships
• So what would a strong correlation be? .90?
  .30? .50?

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Personality Research MethodsInterpreting Data

• Interpreting a correlation Is this relationship
  strong or weak?
• At least two ways to interpret the size of a
  corr
• Research context
• Translate to Probabilities (BESD, in textbook)

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Statistical vs Experimental Control

• What is experimental control? What do we want to
  control when doing an experiment?
• What if we cant do so experimentally?
  Statistical control?
• Multiple regression, partial correlations, etc
• Example Conscientiousness, SAT, and GPA

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Personality Research Methods

• Goals
• Most generally, to become more sophisticated
  consumers of research information
• To understand how we study personality
  empirically
• To appreciate strengths and weaknesses of various
  designs and analyses what they can and cant
  tell us about personality
• Be able to interpret some key types of statistics