Computer information forecasting model
11-16
| Forecasting | 3 period weighted moving average | |||||||
| Input Data | Forecast Error Analysis | |||||||
| Period | Actual value | Weights | Forecast | Error | Absolute error | Squared error | Absolute % error | |
| Month 1 | 622 | 1 | ||||||
| Month 2 | 418 | 2 | ||||||
| Month 3 | 608 | 3 | ||||||
| Month 4 | 752 | 547.000 | 205.000 | 205.000 | 42025.000 | 27.26% | ||
| Month 5 | 588 | 648.333 | -60.333 | 60.333 | 3640.111 | 10.26% | ||
| Month 6 | 656 | 646.000 | 10.000 | 10.000 | 100.000 | 1.52% | ||
| Month 7 | 689 | 649.333 | 39.667 | 39.667 | 1573.444 | 5.76% | ||
| Month 8 | 675 | 661.167 | 13.833 | 13.833 | 191.361 | 2.05% | ||
| Month 9 | 706 | 676.500 | 29.500 | 29.500 | 870.250 | 4.18% | ||
| Month 10 | 725 | 692.833 | 32.167 | 32.167 | 1034.694 | 4.44% | ||
| Average | 55.786 | 7062.123 | 7.92% | |||||
| Next period | 710.333 | MAD | MSE | MAPE |
11-16 Graph
11-16 Graph
11-16 Optimal Weights
| Wallace Garden Supply | ||||||||
| Forecasting | 3 period weighted moving average | |||||||
| Input Data | Forecast Error Analysis | |||||||
| Period | Actual value | Weights | Forecast | Error | Absolute error | Squared error | Absolute % error | |
| Month 1 | 10 | 0.2218 | ||||||
| Month 2 | 12 | 0.5927 | ||||||
| Month 3 | 16 | 0.1855 | ||||||
| Month 4 | 13 | 12.298 | 0.702 | 0.702 | 0.492 | 5.40% | ||
| Month 5 | 17 | 14.556 | 2.444 | 2.444 | 5.971 | 14.37% | ||
| Month 6 | 19 | 14.407 | 4.593 | 4.593 | 21.093 | 24.17% | ||
| Month 7 | 15 | 16.484 | -1.484 | 1.484 | 2.202 | 9.89% | ||
| Month 8 | 20 | 17.814 | 2.186 | 2.186 | 4.776 | 10.93% | ||
| Month 9 | 22 | 16.815 | 5.185 | 5.185 | 26.889 | 23.57% | ||
| Month 10 | 19 | 19.262 | -0.262 | 0.262 | 0.069 | 1.38% | ||
| Month 11 | 21 | 21.000 | 0.000 | 0.000 | 0.000 | 0.00% | ||
| Month 12 | 19 | 20.036 | -1.036 | 1.036 | 1.074 | 5.45% | ||
| Average | 1.988 | 6.952 | 10.57% | |||||
| Next period | 20.185 | MAD | MSE | MAPE | ||||
| Sum of weights = | 1.000 |
Consider the data given in problem below.
___________________________________________________________________
Day Sales Day Sales
___________________________________________________________________
1 $622 6 $656
2 $418 7 $689
3 $608 8 $675
4 $752 9 $706
5 $588 10 $725
____________________________________________________________________
A). If the store wants to use exponential smoothing to forecast the sales volume, what is the optimal value
of a that would minimize MAPE? What is the forecast for day 11 using this model?
B). If the store wants to use linear trend analysis to forecast the sales volume , what is the linear equation
that best fit’s the data? What is the forecast for day 11 using this model ?
C). Which of the methods analyzed would you use?