The following data represent enrollment in a major at your university for the past six semesters (Note: semester 1 is the oldest data; semester 6 is the most recent data):
Semester Enrollment
1………………………….. 87
2………………………….110
3………………………….123
4………………………….127
5………………………….145
6………………………….160
a. Prepare a graph of enrollment for the six semesters.
b. Based on the graph you prepared in part a, does it appear that a trend is present in the enrollment figures?
c. Prepare a single exponential smoothing forecast for semester 7 using an alpha value of 0.35. Assume that the initial forecast for semester 1 is 90.d. Prepare a double exponential smoothing forecast for semester 7 using an alpha value of 0.20 and a beta value of 0.25. Assume that the initial smoothed constant value for semester 1 is 80 and the initial smoothed trend value for semester 1 is 10.e. Calculate the MAD values for the simple exponential smoothing model and the double exponential smoothing model at the end of semester 6. Which model appears to be doing the better job of forecasting course enrollment? Don’t include period 1 in the calculation.