is used to test the hypothesis that the values of the regression parameters B, B1, B2, B, are all zero. a) The least squares method b) Extrapolation c) An F test d) Attest Question 10 (3 points) Listen A variable used to model the effect categorical independent variables in a regression model is known as a a) predictor variable b) dummy variable. c) response. d) dependent variable. We create multiple "dummy variables" for categorical variables rather than enumerate the values as 1, 2, 3, etc. because: a) Excel's Regression tool cannot generate accurate answers that contain multi- valued variables. Ob) these values would imply that 4 is more significant than 1. O c) this is a historical relic from early mathematics that actually could be removed given today's software capabilities. d) Excel can help us encode these variables. Question 12 (3 points) Listen Forward Selection: a) creates every possible combination of regressions for single pairs, triplets, and more of independent variables. b) begins with one berge regression model and removes variables one at a time until all variables are significant Oc) begins with a simple regression for each possible independent variable and adds them one at a time into a multiple regression model until one is not significant; it is removed and that model is kept d) adds one variable and removes one variable in each action as the final model is created