Psychology Research Methods Guide

Study Notes

This guide covers the core research methods in psychology.
Half of Paper 2, and up to a third of the overall marks, in the Psychology A-level are dedicated to research methods.
The scientific method is used to collect and analyze data in psychology.
Psychology, like biology and physics, uses theories to predict and explain behavior.
A wide range of research methods will be covered.
Experiments, Observations, Self-report, Correlational analysis, Content analysis, Thematic analysis, Meta-analysis, and Case Studies are among the methods.

The British Psychological Society (BPS) guidelines dictate the ethical treatment of participants.
Informed consent is mandatory; participants must provide consent.
Deception should only be permissible if there is a justifiable reason to avoid bias and the study's validity.
Participants must be debriefed after the study.
Participants must be protected from harm (physical and psychological).
Confidentiality and participant privacy must be respected.

Repeated measures design: One group of participants completes all tasks
Independent groups design: Different groups complete different tasks.
Matched pairs design: Pairs of participants are carefully matched on relevant variables.
Natural experiments: Researchers observe naturally occurring events or phenomena
Quasi-experiments: Use pre-existing or naturally occurring variables as the independent variable. These studies may not able to establish causality.

A hypothesis is a testable prediction about the outcome of a study.
Hypotheses are statements (not questions) that predict what will occur in a study.
Directional hypotheses predict the direction of the difference or relationship.
Non-directional hypotheses merely predict that a difference or relationship exists.
Null hypotheses state that no significant relationship or effect exists in the study.

Lab observations: Controlled environment for high control but low ecological validity
Naturalistic observations: Real-world setting, high ecological validity but low control.
Participant observations: Researchers participate in the observation
Non-participant observations: Researchers do not participate in the observation.
Covert observations: Participants unaware of observation
Overt observations: Participants aware of observation

It's a technique that identifies and analyzes recurring themes in qualitative data.

Examines the relationship between two or more variables.
Positive correlation: Both variables change in the same direction
Negative Correlation: Variables change in opposite directions.
Correlation coefficient - R: A measure of correlation strength ranging from -1 (perfect negative) to +1 (perfect positive)
Scattergraph/plots: Used to visualize the relationship between two variables

Questionnaires and Interviews.
Strengths: Cheap, quick, easy to repeat, access diverse perspectives
Weaknesses: Low response rate, potential bias, difficult for detailed views
Question Types: Closed (yes/no, multiple choice, likert scales), Open-ended (free form)
Interviews: Structured (sets questions), Semi-structured (some pre-set questions), Unstructured (flexible follow-up questions)

Random: Each member has an equal chance of selection
Opportunity: Participants are selected as they are available.
Volunteer: Participants self-select to participate. Can be influenced by bias.
Systematic: Selecting participants at fixed intervals from a list.
Stratified: Ensures the sample proportionally represents the target population.

Internal Validity: Did the study measure what it intended to measure?
External Validity: Can the results be generalized to other populations or settings?
Predictive Validity: Testing correlation of a measure to a future outcome
Concurrent Validity: Assessing whether a new measure is correlated with an existing valid measure.
Face Validity: Does the measure appear to be measuring what it intends to measure?