Suppose we want to estimate the effects of alcohol consumption (alcohol) on college grade point aver- age (colGPA). In addition to collecting information on grade point averages and alcohol usage, we...

Extracted text: Suppose we want to estimate the effects of alcohol consumption (alcohol) on college grade point aver- age (colGPA). In addition to collecting information on grade point averages and alcohol usage, we also obtain attendance information (say, percentage of lectures attended, called attend). A standardized test score (say, SAT) and high school GPA (hsGPA) are also available. (i) Should we include attend along with alcohol as explanatory variables in a multiple regression model? (Think about how you would interpret Balcohol-) |(ii) Should SAT and hsGPA be included as explanatory variables? Explain.