Two independent methods of forecasting based on judgment and experience have been prepared each month for the past 10 months. the forecasts and actual sales are as follows:
month sales forecast 1 forecast 2
1 840 790 805
2 840 790 830
3 795 790 840
4 810 800 840
5 785 785 805
6 830 775 771
7 765 785 800
8 850 790 800
9 810 795 810
10 830 800 845
a. compute the mse and mad for each forecast. (round your answers to 2 decimal places.)
mse mad
forecast 1 ? ?
forecast 2 ? ?
b. compute mape for each forecast. (round your intermediate calculations to 5 decimal places and final answers to 4 decimal places.)
mape f1 ? %
mape f2 ? %
c. prepare a naive forecast for periods 2 through 11 using the given sales data. compute each of the following; (1) mse, (2) mad, (3) tracking signal at month 10, and (4) 2s control limits. (round your answers to 2 decimal places.)
mse ?
mad ?
tracking signal ?
control limits 0 ± ?