Research methods Revision Notes

Research Methods in Psychology

Experimental Method

• Laboratory Experiments: Conducted in controlled environments, allowing for manipulation of variables. High internal validity but may lack ecological validity.
• Field Experiments: Conducted in natural settings. More ecological validity but less control over extraneous variables.
• Natural Experiments: Researchers observe the effects of naturally occurring events. Useful when manipulation is unethical or impractical.
• Quasi-Experiments: Involves comparison between groups that are not randomly assigned. Useful in real-world settings but can introduce confounding variables.

Observational Techniques

• Naturalistic Observation: Observing behavior in its natural context without interference. High ecological validity but difficult to control variables.
• Controlled Observation: Conducted in a structured environment. Allows for control but may alter behavior.
• Covert vs. Overt: Covert observation is hidden, while overt is known to participants. Covert can reduce demand characteristics.
• Participant vs. Non-Participant: In participant observation, the researcher engages with the group, while in non-participant, they observe from a distance.

Self-Report Techniques

• Questionnaires: Can be structured (fixed responses) or unstructured (open-ended). Useful for gathering large amounts of data but may suffer from response bias.
• Interviews: Structured interviews follow a set format, while unstructured interviews allow for more flexibility. Both can provide in-depth data but may be time-consuming.

Correlations

• Correlations measure the relationship between two variables but do not imply causation. Positive, negative, and zero correlations indicate different types of relationships.

Content Analysis and Case Studies

• Content Analysis: A qualitative method for analyzing communication content. Coding is essential for quantifying data.
• Case Studies: In-depth studies of individuals or groups. Provide rich qualitative data but may lack generalizability.

Sampling Methods

• Random Sampling: Every member has an equal chance of selection, reducing bias.
• Systematic Sampling: Every nth member is selected, which can introduce bias if there is a pattern.
• Stratified Sampling: Ensures representation from various subgroups, enhancing generalizability.
• Opportunity and Volunteer Sampling: Easier to conduct but can lead to bias.

Experimental Design

• Independent Measures: Different participants in each condition, reducing order effects.
• Repeated Measures: Same participants in all conditions, controlling for participant variables but risking order effects.
• Matched Pairs: Participants matched on key characteristics, balancing individual differences.

Ethical Considerations

• Informed consent, confidentiality, and the right to withdraw are crucial in psychological research.

Reliability and Validity

• Reliability refers to consistency of results, while validity refers to whether a study measures what it claims to measure.

Data Types

• Quantitative Data: Numerical data that can be statistically analyzed.
• Qualitative Data: Descriptive data that provides insights into participants' thoughts and feelings.

Statistical Analysis

• Measures of central tendency (mean, median, mode) and measures of dispersion (range, standard deviation) help summarize data.
• Understanding normal and skewed distributions is essential for interpreting data correctly.
• Statistical tests (e.g., t-tests, Chi-Squared) are used to determine significance, with Type I and Type II errors being critical considerations.