Question

store managers wishes to forecast the weekly number of television sets sold. Calculate the error for each of the following forecasts, the MAD and the MSE. Be sure to show the entire table in the work area of the template. Period        Value Forecast Error 1                             202   —           — 2                             191   202     3                             173   192     4                             169   181     5                             171   174     6                             175   172     7                             182   174     8                             196   179     9                             204   189 10                          219   198 11                  227   211                

Answer 1

Period t	Actual At	Forecast Ft	Error At - Ft	|Error|	Error2
1	202	_
2	191	202	-11	11	121
3	173	192	-19	19	361
4	169	181	-12	12	144
5	171	174	- 3	3	9
6	175	172	3	3	9
7	182	174	8	8	64
8	196	179	17	17	289
9	204	189	15	15	225
10	219	198	21	21	441
11	227	211	16	16	256
				Σ=125	Σ=1919

MAD = Mean absolute deviation

=(sum of absolute errors)/(number of period)

= 125 / 10

= 12.5

MAD = 12.5

MSE = Mean squared error

= Σ (Error² ) / (number of periods)

= 1919 / 10

= 191.9

MSE = 191.9