HBK, a food industry company wants to build a forecasting model to predict the sales of its hot-beverage. HBK had the last weekly sales for the past 152 weeks. Using the time series components for trend (variable called tp) and seasonal--monthly dummy variables (using Dec as a baseline) and the causal variable of average weekly temperature HBK management build the model on the following page.

Note the average hot-beverage weekly sales is $91,500.

a. Evaluate the model on the following page, i.e., is it a good model? If so, why, or if not, why? Consider all the appropriate tests, use = 0.05 for t test and = 0.05 for F test. Notice on the following page is a plot of the residuals.