When selecting a variable to predict an outcome, select a predictor variable (X) that is related to the criterion variable (Y). That way, the two share something in common (remember, they should be correlated). When selecting more than one predictor variable (such as X1 and X2), try to select variables that are independent or uncorrelated with one another but are both related to the outcome or predicted (Y) variable. In effect, you want only independent or predictor variables that are related to the dependent variable and are unrelated to each other. That way, each one makes as distinct a
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