17 Question 15 (17 Marks) Marks This question consists of five parts, part (a) to (e). Consider a model explaining the weekly sales, S measured in 100's cans sold, of a popular brand of canned tuna (the "Blue Sea" brand) as a function of its price (P = price in cents), the price of a competitor (PC, also in cents), and advertising. To capture advertising, the model Includes a dummy variable DISP = 1 if there is a store display but no newspaper ad during the week for Blue Sea brand, and 0 otherwise; and a dummy variable DISPAD = 1 if there is a store display and newspaper ads during the week for the Blue Sea brand, and 0 otherwise. The model is as follows: In(S) = B1 + B2P + BaPC+ BADISP + BDISPAD + e (1) The estimated log-linear model using data from 52 weeks is as follows (standard errors in parentheses): In(S) = 8.9800 - 0.0375 P + 0.0115 PC + 0.4240 DISP + 1.4310 DISPAD (2) (0.6460) (0.0058) (0.0045) (0.1050) (0.1560) (se) R2 = 0.84 N = 52 To answer this question you may find the following useful for F critical values. When F(as) is an F distributed random variable with numerator degree of freedom a and denominator degree of freedom b: . Pr( F(2,46)