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A cognitive psychologist wants to set up a between-subjects experiment to compare two types of memory training. How should they apply random assignment to ensure their experimental groups are equivalent?
Question: A cognitive psychologist wants to set up a between-subjects experiment to compare two types of memory training. How should they apply random assignment to ensure their experimental groups are equivalent?
Sample answer: The psychologist should assign each participant to one of the memory training conditions using a random method, such as a computer generator or coin flip. This ensures that every participant has an equal chance of being in either group, minimizing systematic pre-existing differences to create equivalent groups.
Key points:
- Apply a random assignment method to allocate participants to memory training conditions.
- Eliminate systematic pre-existing differences through the allocation process.
- Ensure the resulting groups are highly similar and equivalent.
Rubric: Award full credit if the response states that the psychologist should randomly assign participants to conditions (1 point) and explains that this application creates highly similar groups by eliminating or minimizing systematic pre-existing differences (1 point).
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Research Methods in Psychology - 4th American Edition @ KPU
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A cognitive psychologist wants to set up a between-subjects experiment to compare two types of memory training. How should they apply random assignment to ensure their experimental groups are equivalent?