McGill Company sales. The data below show seasonally adjusted quarterly sales for the McGill Company (Y, in million dollars) and for the entire industry (X, in million dollars) for the most recent 20 quarters
a. Would you expect the autocorrelation parameter p to be positive. negative or zero here?
b. Fit a simple linear regression model by ordinary least squares and obtain the residuals. Also obtain 
d. Conduct a formal test for positive autocorrelation using α = .01. State the alternative decision rule. and conclusion. Is the residual analysis in part (c) in accord with the test result?