Exercise 7-7 A&D Electronics
Holt’s Model Holt’s model with alpha = 0.5 and beta = 0.5
Period Sales Level Trend Forecast
EtAtBias MSE MAD
Percent
Error
MAPE TS
0948 109
1 1,000 1,029 94.8 1,057 57 57 57 3,249 57 5.7 5.7 1.00
2 1,113 1,118 92.2 1,123 10 10 67 1,677 34 0.9 3.3 2.00
3 1,271 1,241 107.4 1,210 -61 61 7 2,346 43 4.8 3.8 0.15
4 1,445 1,397 131.6 1,348 -97 97 -90 4,111 56 6.7 4.5 -1.61
5 1,558 1,543 139.1 1,528 -30 30 -120 3,467 51 1.9 4.0 -2.36
6 1,648 1,665 130.5 1,682 34 34 -86 3,084 48 2.1 3.7 -1.79
7 1,724 1,760 112.6 1,796 72 72 -15 3,376 52 4.2 3.8 -0.28
8 1,850 1,861 107.0 1,872 22 22 8 3,017 48 1.2 3.4 0.16
9 1,864 1,916 81.0 1,968 104 104 112 3,889 54 5.6 3.7 2.07
10 2,076 2,037 100.7 1,997 -79 79 33 4,123 57 3.8 3.7 0.59
11 2,167 2,152 108.1 2,137 -30 30 3 3,829 54 1.4 3.5 0.06
12 2,191 2,226 90.8 2,260 69 69 73 3,909 55 3.2 3.4 1.31
13 2,316
14 2,407
Estimate of standard deviation of forecast error: 69.29
Exercise 7-7 A&D Electronics
Holt’s Model Holt’s model with alpha = 0.05 and beta = 0.1
Period Sales Level Trend Forecast
EtAtBias MSE MAD
Percent
Error
MAPE TS
0948 109
1 1,000 1,054 108.7 1,057 57 57 57 3,249 57 5.7 5.7 1.00
2 1,113 1,160 108.5 1,163 50 50 107 2,868 53 4.5 5.1 2.00
3 1,271 1,269 108.5 1,269 -2 2105 1,913 36 0.2 3.5 2.88
4 1,445 1,381 108.8 1,377 -68 68 37 2,577 44 4.7 3.8 0.84
5 1,558 1,493 109.2 1,490 -68 68 -31 2,997 49 4.4 3.9 -0.64
6 1,648 1,604 109.4 1,602 -46 46 -77 2,847 48 2.8 3.7 -1.59
7 1,724 1,714 109.4 1,714 -10 10 -87 2,455 43 0.6 3.3 -2.03
8 1,850 1,825 109.6 1,824 -26 26 -113 2,234 41 1.4 3.0 -2.77
9 1,864 1,931 109.2 1,935 71 71 -43 2,541 44 3.8 3.1 -0.97
10 2,076 2,042 109.4 2,040 -36 36 -78 2,414 43 1.7 3.0 -1.81
11 2,167 2,152 109.5 2,152 -15 15 -94 2,216 41 0.7 2.8 -2.30
12 2,191 2,258 109.1 2,262 71 71 -23 2,449 43 3.2 2.8 -0.53
13 2,367
14 2,476
Estimate of standard deviation of forecast error: 54.13