The number of flowers sold at The Blossom Shop on Fridays is shown in the table
ID: 2260813 • Letter: T
Question
The number of flowers sold at The Blossom Shop on Fridays is shown in the table below.
Week
Demand
Week
Demand
Week
Demand
1
55
6
63
11
69
2
50
7
50
12
52
3
57
8
50
13
67
4
60
9
58
14
63
5
58
10
73
15
70
Round off all calculations to two decimal places. Maintaining two decimal places is required for all calculations
What is the period 15 tracking signal for the forecast with = 0.6?
Week
Demand
Week
Demand
Week
Demand
1
55
6
63
11
69
2
50
7
50
12
52
3
57
8
50
13
67
4
60
9
58
14
63
5
58
10
73
15
70
Explanation / Answer
exponential smoothing forecast:
Ft, Ft-1 = Forecasts for period t and t-1 respectively
At-1 = Actual demand for period t-1
Alpha = Exponential smoothing factor = 0.6
Therefore,
Ft = 0.6 x At-1 + 0.4x Ft-1
Also following formula to be noted :
Please refer below table which highlights “Error” as well as “Absolute deviation” for each week
Week
Demand
Forecast
Error
Absolute deviation (AD)
1
55
55.00
0.00
0.00
2
50
55.00
-5.00
5.00
3
57
52.00
5.00
5.00
4
60
55.00
5.00
5.00
5
58
58.00
0.00
0.00
6
63
58.00
5.00
5.00
7
50
61.00
-11.00
11.00
8
50
54.40
-4.40
4.40
9
78
51.76
26.24
26.24
10
73
67.50
5.50
5.50
11
69
70.80
-1.80
1.80
12
52
69.72
-17.72
17.72
13
67
59.09
7.91
7.91
14
63
63.84
-0.84
0.84
15
70
63.33
6.67
6.67
SUM=
20.56
102.07
Accordingly,
Mean absolute Deviation ( MAD ) = 102.07 / 15 = 6.804
Sum of errors =20.56
Therefore ,
Tracking signal = Sum of errors/ MAD = 20.56/6.804 = 3.021 ( GREATER THAN 2 BUT LESS THAN OR EQUAL TO 4)
ANSWER : GREATER THAN 2 BUT LESS THAN OR EQUAL TO 4
Week
Demand
Forecast
Error
Absolute deviation (AD)
1
55
55.00
0.00
0.00
2
50
55.00
-5.00
5.00
3
57
52.00
5.00
5.00
4
60
55.00
5.00
5.00
5
58
58.00
0.00
0.00
6
63
58.00
5.00
5.00
7
50
61.00
-11.00
11.00
8
50
54.40
-4.40
4.40
9
78
51.76
26.24
26.24
10
73
67.50
5.50
5.50
11
69
70.80
-1.80
1.80
12
52
69.72
-17.72
17.72
13
67
59.09
7.91
7.91
14
63
63.84
-0.84
0.84
15
70
63.33
6.67
6.67
SUM=
20.56
102.07