week 3 stats hw
Table 5.2
| Walace Garden Center Data Figure 5.2 | ||||
| Sales | Test Center | Absolute Value of Error | 3 Month Moving Average | Absolute Value of Error |
| Jan | 10 | 10.00 | --- | --- |
| Feb | 12 | 12.00 | --- | --- |
| Mar | 13 | 13.00 | --- | --- |
| Apr | 16 | 16.00 | 0.00 | 0.00 |
| May | 19 | 19.00 | 0.00 | 0.00 |
| Jun | 23 | 23.00 | 0.00 | 0.00 |
| Jul | 26 | 26.00 | 0.00 | 0.00 |
| Aug | 30 | 30.00 | 0.00 | 0.00 |
| Sep | 28 | 28.00 | 0.00 | 0.00 |
| Oct | 18 | 18.00 | 0.00 | 0.00 |
| Nov | 16 | 16.00 | 0.00 | 0.00 |
| Dec | 14 | 14.00 | 0.00 | 0.00 |
| Jan | --- | --- | 0.00 | --- |
| Sum of Abs Val of Error | 190.00 | Sum of Abs Val of Error | 0.00 | |
| MAD | 21.11 | MAD | 0.00 | |
| Hence "on the average, each forecast missed the actual value by" | 6.48 units | |||
| p. 155 |
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 10 12 13 16 19 23 26 30 28 18 16 14
Table 5.4
| Quarter | Tonnage | F(t+1) |
| 1 | 180 | 175.00 |
| 2 | 168 | 175.50 |
| 3 | 159 | 174.75 |
| 4 | 175 | 173.18 |
| 5 | 190 | 173.36 |
| 6 | 205 | 175.02 |
| 7 | 180 | 178.02 |
| 8 | 182 | 178.22 |
| 9 | --- | 178.60 |
Table 5.8
| Table 5.8 | |||||
| Year 1 | Year 2 | 2-year average | Seasonal Index | Year 3 Forecast | |
| Jan | 80 | 100 | 90 | 0.9574468085 | 95.7 |
| Feb | 85 | 75 | 80 | 0.8510638298 | 85.1 |
| Mar | 80 | 90 | 85 | 0.9042553191 | 90.4 |
| Apr | 110 | 90 | 100 | 1.0638297872 | 106.4 |
| May | 115 | 131 | 123 | 1.3085106383 | 130.9 |
| Jun | 120 | 110 | 115 | 1.2234042553 | 122.3 |
| Jul | 100 | 110 | 105 | 1.1170212766 | 111.7 |
| Aug | 110 | 90 | 100 | 1.0638297872 | 106.4 |
| Sep | 85 | 95 | 90 | 0.9574468085 | 95.7 |
| Oct | 75 | 85 | 80 | 0.8510638298 | 85.1 |
| Nov | 85 | 75 | 80 | 0.8510638298 | 85.1 |
| Dec | 80 | 80 | 80 | 0.8510638298 | 85.1 |
| Total | 1128 | Forecast | 1200 | ||
| Average | 94 | Average | 100 |
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 90 80 85 100 123 115 105 100 90 80 80 80