effect size(redirected from Cohen's d)
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A measurement of the effects of treatment, the absolute differences that the treatment produces, and not only the fact that the treatment reliably produces some effect, no matter how small. For example, in assessing the impact of a treatment for cancer, two forms of chemotherapy might each result in prolongation of life. If each treatment is well tolerated, the one that reliably prolongs life by several years has a greater effect size than the other, which prolongs life by only several weeks.