A Note on Cohen's d From a Partitioned Linear Regression Model
In this note we introduce a generalized formula for Cohen's d under the presence of additional independent variables, providing a measure for the size of a possible effect concerning the location difference of a variable in two groups. This is done by employing the so-called Frisch-Waugh-Lovell theorem in a partitioned linear regression model. The generalization is motivated by demonstrating the relationship to appropriate t and F statistics. Our discussion is further illustrated by inference from a publicly available data set.
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