Foundations of Research in Psychology

Why research matters in psychology
- Psychology is the scientific study of mind and behavior; research provides the scientific foundation for claims about how people think, feel, and act.
- Historically, people believed the earth was flat; some beliefs persist without evidence. Research helps distinguish beliefs from evidence-based conclusions.
- Early explanations of mental illness included demonic possession; these ideas lacked empirical evidence.
- People have personal beliefs about the world, but claims must be supported by objective, repeatable evidence.
- Without research, we rely on guesses; research provides a cohesive picture of how the world works.
- Psychology, as a science, relies on the scientific method to create, test, and verify ideas.
- A picture (illustration) referenced: trephination—drilling holes in the skull to release evil spirits; this is no longer used due to advances in research and understanding.
Core concepts in scientific psychology
- Theory: a well-developed set of ideas that explain an observed phenomenon (e.g., a theory about bullying in middle school).
- Hypothesis: a testable prediction about the relationship between two or more variables; typically stated as an if–then statement.
- Example: “If a child is lonely and has no friends, then he is more likely to bully other children.”
- Observations lead to hypotheses; hypotheses guide research and can be supported or refuted, feeding back into theory.
- Operational definitions: precise, specific descriptions of how variables will be measured and manipulated; they define the exact procedures and measures used.
- Importance: without precise definitions, researchers and readers wouldn’t know exactly what was measured or how.
Research methods in psychology (overview)
- Clinical or case studies
- Naturalistic observation
- Surveys
- Archival research
- Longitudinal and cross-sectional research
Case study example and limitations
- Jeffrey Dahmer as an example of a case study: in-depth information about one individual with extreme/unique psychological circumstances.
- Benefits: provides rich, detailed information and insights about a single case.
- Limitations: difficult to generalize to the larger population; high variability across individuals; cannot easily inform about causation or population-level patterns.
- Takeaway: case studies are valuable for exploratory insights but not for broad generalizations.
Naturalistic observation
- Definition: observing behavior in natural settings (e.g., watching middle schoolers on a playground).
- Researchers are typically hidden from view to minimize reactivity; use one-way mirrors or discreet presence.
- Strength: reveals what happens in real-world contexts; useful for describing behavior.
- Limitation: does not provide direct insight into why behavior occurs; limited ability to infer causation.
- Observer bias: researchers’ expectations can shape what they notice or record; risk of selectively focusing on expected findings (e.g., watching boys for aggression due to expectation of gender differences).
- Important caveat: always consider observer bias and how it might influence interpretations.
Surveys
- Definition: a list of questions delivered in various formats (paper, online, or verbally).
- Strength: can collect data from large samples; efficient for gathering information about a population.
- Key concepts: population (the entire group of interest) and sample (a subset selected for the study).
- Random sampling is ideal to ensure the sample represents the population; random assignment is used in experiments to create equivalent groups.
- Convenience samples are common but may introduce bias; strive for random sampling when possible.
Archival research
- Definition: analyzing past records or data to answer research questions or identify patterns.
- Benefit: leverages existing data, can expand theories without starting from scratch.
Cross-sectional vs. longitudinal research
- Cross-sectional: collect data from different segments of a population at a single point in time (e.g., compare older and younger adults on coping with depression at one time).
- Longitudinal: study the same group of people over an extended period (e.g., track individuals from childhood into adulthood).
- Key challenge of longitudinal research: attrition—the dropout of participants over time, which can bias results and reduce sample size.
- Cross-sectional studies avoid attrition but cannot capture developmental changes over time.
Correlational research
- Goal: examine relationships between two or more variables; determine if they are related and how strong the relationship is.
- Correlation coefficient: a numerical value denoted by r that ranges from
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