Overview
This lecture covers the main research methods used in psychology, their strengths and weaknesses, and the differences between key research designs and concepts such as correlation and causation.
Research Methods in Psychology
- Psychologists use various methods including case studies, naturalistic observation, surveys, and archival research to study behavior and mental processes.
- Each method offers unique advantages and limitations depending on the research question.
Case Studies
- Clinical or case studies focus on one or a few individuals, providing deep, detailed information about rare or unique cases.
- Main strength: unmatched depth of insight into specific phenomena.
- Main weakness: difficult to generalize findings to the wider population due to small, non-representative samples.
Naturalistic Observation
- Researchers observe behaviors in natural settings without interference to increase ecological validity (realism).
- Observer must remain unobtrusive to avoid influencing subjects' behavior.
- Strength: produces accurate, realistic data that generalizes well to real life.
- Weaknesses: hard to control variables, time-consuming, and subject to observer bias.
- Observer bias and inter-rater reliability are key concerns to address in this method.
Surveys
- Surveys collect self-reported data from large samples quickly and efficiently, increasing generalizability.
- Strength: can gather information from large, diverse groups quickly.
- Weaknesses: responses may be inaccurate due to dishonesty, memory errors, or social desirability.
- Measures of central tendency (mean, median, mode) summarize survey data but can be influenced by outliers.
Archival Research
- Involves analyzing existing records to identify trends and relationships.
- Strength: low cost, no need to recruit participants.
- Weaknesses: limited to available data, lack of control over how/what data was collected, and potential inconsistency between sources.
Longitudinal vs. Cross-Sectional Research
- Longitudinal research studies the same group over time to observe changes, minimizing cohort effects.
- Cross-sectional research compares different groups at one point in time, saving time but subject to generational differences.
- Longitudinal studies allow for stronger generalizations but are expensive, time-intensive, and prone to participant dropout (attrition).
Correlation vs. Causation
- Correlational studies identify relationships between variables but cannot confirm cause-and-effect.
- Only experimental research, with control over variables, can determine causation.
Key Terms & Definitions
- Case Study — in-depth analysis of one or a few individuals.
- Naturalistic Observation — observing behavior in natural contexts without interference.
- Survey — self-reported data collected through questionnaires.
- Archival Research — analysis of pre-existing data or records.
- Longitudinal Research — repeated observations of the same subjects over time.
- Cross-Sectional Research — comparison of different groups at a single point in time.
- Correlation — a relationship between two variables.
- Causation — one variable directly causes a change in another.
- Ecological Validity — how well findings generalize to real-world settings.
- Inter-rater Reliability — consistency among different observers' ratings.
- Attrition — loss of participants over time in a longitudinal study.
Action Items / Next Steps
- Review the chapter on experimental research for details on how causality is established.
- Read about the Strange Situation procedure in the lifespan development chapter.