This mini-lesson covers OCR Research Methods: writing hypotheses and identifying variables, research designs and sampling, ethics, 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 OCR GCSE Psychology (J203) Research Methods content. Press Start when you're ready.
Research methods · variables
Hypotheses & variables
A hypothesis is a clear, testable prediction.
Independent variable (IV) — what the researcher changes.
Dependent variable (DV) — what the researcher measures.
Extraneous variables — other factors that must be controlled.
A null hypothesis predicts no difference; an alternative hypothesis predicts there will be one.
Quick check
Spot the DV
?A study tests whether revision method (flashcards vs re-reading) affects test scores. What is the dependent variable?
Research methods · design
Experimental designs & sampling
Designs decide how participants are used:
Independent groups — different people in each condition.
Repeated measures — the same people in every condition.
Matched pairs — different people paired on key traits.
Sampling selects participants: random, opportunity and systematic are common methods.
Quick check
Which design?
?The same participants complete both a quiet condition and a noisy condition. Which experimental design is this?
Research methods · ethics
Ethical issues
Researchers must protect participants. Key issues include:
Informed consent and the right to withdraw.
Avoiding or justifying deception, followed by a debrief.
Protection from harm and confidentiality.
Sort it
Sort the research terms
Tap a term, then tap the group it belongs to.
⚖️ Ethical issue
🧪 Experimental design
🎯 Sampling method
Calculate
Calculate the mean
#Five test scores are: 7, 9, 6, 8, 10. Calculate the mean.
Hint: add them (7+9+6+8+10 = 40) then divide by 5.
Calculate
Find the median
#Five reaction times (in seconds) are: 4, 2, 7, 3, 5. Put them in order and find the median.
s
Hint: in order they are 2, 3, 4, 5, 7 — pick the middle one.
Calculate
Calculate the range
#The highest score is 22 and the lowest is 7. Calculate the range.
Hint: range = highest − lowest = 22 − 7.
Calculate
Work out a percentage
#In a sample, 15 out of 50 participants conformed. What percentage conformed?
%
Hint: (15 ÷ 50) × 100.
Match it
Match the method term
Tap a description on the left, then its matching term on the right.
Statement
Answer
Quick check
Types of data
?A researcher counts the exact number of correct answers each participant gives. This is which type of data?
Quick check
Central tendency
?Which measure of central tendency is the most frequently occurring value?
Recap
The big ideas to know
Variables: IV (changed) · DV (measured) · extraneous (controlled)
Hypotheses: null (no effect) vs alternative
Designs: independent groups · repeated measures · matched pairs