Homework SoursePeriod 1 2 3 4 5 6 7 Demand 15 13 11 12 21 14 10 a Forecast
Period 1 2 3 4 5 6 7
Demand 15 13 11 12 21 14 10
a) Forecast the demand for Period 8 using a three-period weighted moving average with weights 5,4, and 1, applying 5 to the most recent data and 1 to the oldest data
b) Calculate the MAD for the forecast in part a
Solution
Sol)
Weighted Moving Averaage
MAD =Absolute Error =15.67 / 3 =5.22
| Yi | Y hat | error | abs(error) |
| 15 | |||
| 13 | |||
| 11 | 13 | -2 | 2 |
| 12 | 12 | 0 | 0 |
| 21 | 14 | -7 | 7 |
| 14 | 15.667 | -1.67 | 1.67 |
| 10 | 15 | -5 | 5 |
| Sum= | 15.67 |
