The Bookstore Data Concerns Weekly Sales At Pages Bookstore Sales Pages Weekly Advertising Expenditure Adver And T 1 (35.8 KiB) Viewed 59 times
The Bookstore Data Concerns Weekly Sales At Pages Bookstore Sales Pages Weekly Advertising Expenditure Adver And T 2 (60.11 KiB) Viewed 59 times
The bookstore data concerns weekly sales at Pages Bookstore (Sales), Pages weekly advertising expenditure (Adver), and the weekly advertising expenditure of Pages main competitor (Compadv). Here, the sales values are expressed in thousands of dollars, and the advertising expenditure values are expressed in hundreds of dollars. [Download the Pages Bookstore Dataset here.] In an excel spreadsheet, estimate a simple linear regression that relates sales (y) with Pages advertising (x1) expenditure. y = bo + bixi tr Obtain the normal probability plot and residual plot from the simple linear regression model. Comment on the model assumptions by conducting a residual analysis. Are all the regression model assumptions satisfied? (a) Comment on mean zero assumption. (b) Comment on constant variance assumption. (c) Comment on independence assumption. (d) Comment on normality assumption.