Question

The manager of a travel agency has been using a seasonally adjusted forecast to predict demand for packaged tours. The actual and predicted values are as follows:

Period			Demand			Predicted
	1			135			113
	2			195			200
	3			155			150
	4			90			102
	5			85			80
	6			130			135
	7			125			128
	8			130			124
	9			95			109
	10			150			150
	11			105			94
	12			90			80
	13			125			140
	14			135			128

     

a. Compute MAD for the fifth period, then update it period by period using exponential smoothing with ? = .05. (Round your intermediate calculations and final answers to 3 decimal places.)

t Period	A Demand	MADt
1	135
2	195
3	155
4	90
5	85
6	130
7	125
8	130
9	95
10	150
11	105
12	90
13	125
14	135

b. Compute a tracking signal for periods 5 through 14 using the initial and updated MADs. (Negative values should be indicated by a minus sign. Round your intermediate calculations and final answers to 3 decimal places.)

t Period	A Demand	Tracking Signal
1	135
2	195
3	155
4	90
5	85
6	130
7	125
8	130
9	95
10	150
11	105
12	90
13	125
14	135

Answer 1

(a) MADs and (b) Tracking Signals are calculated as below

Formula:

D7 =D6+(B6-D6)*0.05 copy to D7:D15

E6 =ABS(B6-C6) copy to E7:E15

F6 =B6-C6 copy to F7:F15

G6 =F6+G5 copy to G6:G15

H6 =G6/AVERAGE($E$6:E6) copy to H6:H15