Statistics and Probability Dictionary
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differently after they receive a treatment, even if the
treatment is neutral. A neutral treatment that
has no "real" effect on the dependent variable is called a
placebo, and a subject's positive response
to a placebo is called the placebo effect.
To control for the placebo effect, researchers often
administer a neutral treatment (i.e., a placebo) to the
The classic example is using a sugar pill in drug
research. The drug is effective only if subjects who
receive the drug have better outcomes than subject who
receive the sugar pill.