13. After graduation, you take a position at Top-Slice, a wellknown manufacturer of golf balls. One of your duties is to forecast monthly demand for golf balls. Using the following data, you developed a regression model that expresses monthly sales as a function of average temperature for the month:

a. (**) Using Equations 9-8 and 9-9 from the text, show how the a and b values of -767.7 and 98.5 were calculated.

b. (*) Use the regression forecasting model to forecast total golf ball sales for June and July 2004. Average temperatures are expected to be 76 degrees in June and 82 degrees in July.

c. (*) Is the regression model just used a time series or a causal forecasting model? Explain.

Transcribed Image Text:

Monthly sales =-767.7 + 98.5(average temperature)