Discuss the below in detail:
Q: For each model compute the Mean Absolute Deviation.
Choose the best-fitting model according to the MAD criteria.
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| year | 
demmand | 
3 yr avg | 
4 yr avg | 
exp smoothing | 
Naïve | 
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| 1 | 
7 | 
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6 | 
  | 
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| 2 | 
9 | 
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6.3 | 
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7 | 
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| 3 | 
5 | 
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7.11 | 
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9 | 
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| 4 | 
9 | 
7 | 
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6.477 | 
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5 | 
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| 5 | 
13 | 
7.6666 | 
7.5 | 
7.233 | 
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9 | 
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| 6 | 
8 | 
9 | 
9 | 
8.96 | 
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13 | 
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| 7 | 
12 | 
10 | 
8.75 | 
8.67 | 
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8 | 
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| 8 | 
13 | 
11 | 
10.5 | 
9.67 | 
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12 | 
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| 9 | 
9 | 
11 | 
11.5 | 
10.6 | 
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13 | 
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| 10 | 
11 | 
11.333 | 
10.5 | 
10.19 | 
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9 | 
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| 11 | 
7 | 
11 | 
11.25 | 
9.4 | 
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11 |