Welcome to Randomization!
Most of us have encountered the idea that randomization is important for proper experimental design, but may have less clear guidance on how to randomize or why randomization is so important. We also might be distracted by common appeals to the “randomness” of winning lottery numbers or other patterned behaviors that feel like pure chance.
Randomization in experimental design is about systematically and thoughtfully imposing an order onto our treatment of variables. Specifically, randomization is a series of actions that reduce the interference of confounding variables and disturbance variables as you study causal relationships. Intentional action like this doesn’t feel very random, and that’s on purpose.
This unit will help you examine the potential ramifications of not controlling for confounding factors, which would skew your results and prevent you from collecting useful data. They also supply an opportunity to explore a few randomization methods that can be applied in your own research.
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References:
Randomization
References: Randomization
Updated May 30, 2025.
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