Covariate

In statistics, a covariate is a variable that is possibly predictive of the outcome under study. A covariate may be of direct interest or be a confounding variable or effect modifier. Also called covariable. An independent variable, or predictor, in a regression equation. Also, a secondary variable that can affect the relationship between the dependent variable and independent variables of primary interest in a regression equationIn econometrics, term "control variable" is usually used instead of covariate.
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