regression to the mean

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regression to the mean

The likelihood that over time probable events will occur and a normal distribution of events rather than that rare, unlikely, or unusual events will unfold.
References in periodicals archive ?
Thus uncontraed studies include in "treatment effects" the possible contribution of placebo effects and regression toward the mean (RTM).
Untreated control groups are needed to control for regression toward the mean (caused by participants who selectively enter studies near the peak of their symptoms and subsequently improve somewhat without treatment).
Medicare Capitation Payments to HMOs in Light of Regression Toward the Mean in Health Care Costs.