This mini-lesson covers AQA Research Methods: writing hypotheses and identifying variables, research designs and sampling, ethical issues, types of data, and how to calculate the mean, median, mode and range.
Work through each screen, answer the questions as you go and collect ⭐ stars. Every fact here is anchored to a named study or theory on the AQA GCSE Psychology (8182) Research Methods content. Press Start when you're ready.
Independent variable (IV) — what the researcher changes.
Dependent variable (DV) — what the researcher measures.
Extraneous variables — other things that could affect the DV and must be controlled.
A null hypothesis predicts no difference or effect; an alternative (experimental) hypothesis predicts there will be one.
Quick check
Spot the variables
?A study tests whether background music (music vs silence) affects test scores. What is the dependent variable?
Research methods · design
Experimental designs & sampling
Experimental designs decide how participants are allocated:
Independent groups — different people in each condition.
Repeated measures — the same people do every condition.
Matched pairs — different people, paired on key characteristics.
Sampling is how you choose participants — e.g. random (everyone has an equal chance), opportunity (whoever is available) and systematic (every nth person).
Quick check
Which design?
?The same group of participants completes a memory task once with music and once in silence. Which experimental design is this?
Research methods · ethics
Ethical issues
Psychologists must protect participants. Key ethical issues (from the BPS guidelines) include: