An educational psychologist is investigating the effectiveness of a new mnemonic technique on vocabulary retention. To control for individual differences in baseline memory capacity, she first measures the short-term memory span of 40 students. She ranks their scores from highest to lowest, groups them into 20 pairs with similar spans, and then randomly assigns one member of each pair to the mnemonic training condition and the other to the rote-learning control condition.
Which experimental design has the psychologist used?
Independent groups
Matched pairs
Repeated measures
Single-case design
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.