Overview
This lecture reviews key research methods concepts for psychology students, focusing on definitions, strengths, weaknesses, and practical applications for the 9990 syllabus Paper 2.
Laboratory Experiments
- Strict control over independent (manipulated) and dependent (measured) variables.
- Conducted in unfamiliar settings, which lowers ecological validity.
- Strength: Allows implementation of controls, increasing reliability and validity.
- Best for studies requiring high control and not easily conducted in real-world settings.
Deception in Research
- Deception: Withholding full details of the study’s purpose from participants.
- Used to reduce demand characteristics (participants changing behavior based on study expectations).
- Ethically acceptable if justified and no harm is caused; always explain reasons for use in your methodology.
Sampling Methods: Opportunity Sample
- Participants selected based on availability at the time and location of the study.
- Often familiar to the experimenter or the environment is familiar.
- Participants can sometimes self-select, blurring lines with volunteer sampling.
Use of Stooges
- Stooge: An actor controlled by the experimenter to create deception and elicit genuine participant behavior.
Qualitative Data
- Data in words, phrases, or sentences, not numbers.
- Collected via interviews, observations, or open-ended questionnaires.
- Useful for understanding participant motivations but harder to analyze statistically.
Longitudinal Studies
- Research conducted over an extended period (months, years).
- Compare data over time to study development or behavioral change.
- Strength: Tracks changes/milestones; Weakness: Participants may drop out.
Independent Measures Design
- Different participants are used for each condition of the independent variable.
- Reduces demand characteristics, but requires more participants.
- Each group experiences only one level of the independent variable.
Objectivity in Research
- Objective data: Unbiased, not affected by individual beliefs/feelings (e.g., numerical data).
- Ensures consistency between researchers and supports scientific reliability.
Questionnaires & Interviews
- Questionnaires: Written method of gathering data; can be anonymous.
- Interviews: Verbal method; face-to-face may influence truthful responses.
- Open-ended questions allow for detailed answers (qualitative), while closed questions produce short, often numerical data (quantitative).
Key Terms & Definitions
- Laboratory Experiment — A study conducted in a controlled, artificial environment.
- Deception — Intentionally misleading participants about the true purpose of a study.
- Demand Characteristics — Participant cues about the study that influence their behavior.
- Opportunity Sample — Participants selected based on availability and willingness at the time of the study.
- Stooge — An individual acting under experimenter instructions to manipulate scenarios.
- Qualitative Data — Non-numerical data, usually descriptive and detailed.
- Longitudinal Study — Research collecting data from the same subjects over long periods.
- Independent Measures Design — Experimental design using separate groups for each condition.
- Objectivity — Unbiased measurement not influenced by personal feelings.
- Questionnaire — A written set of questions to gather participant data.
- Open-ended Question — A question allowing detailed, unrestricted responses.
Action Items / Next Steps
- Review the vocab list in the lecture description.
- Prepare to justify ethical choices (like deception) in research design questions.
- Practice defining and giving examples of research methods and data types.