What is the purpose of random assignment in an experiment?
Answer and explanation
Correct answer: D. To make the groups similar, so differences reflect the treatment
- Step 1: Chance balances other factors across the groups. Step 2. Differences in outcomes can then be linked to the treatment. Answer: to make the groups similar. Why not the others: Random sampling ensures representative sample selection from a population, whereas random assignment balances confounding variables across treatment arms in an experiment.
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