11.35 Multiple linear regression model. Now consider a regression model using all three explanatory variables.

  1. (a) Write out the statistical model for this analysis, making sure to specify all assumptions.

  2. (b) Run the multiple regression model and specify the fitted regression equation.

  3. (c) Generate a 95% confidence interval for each coefficient. Should any of these intervals contain 0? Explain.

  4. (d) What percent of the variation in total score is explained by this model? What is the estimate for σ?