1. National scan, Inc., sells radio frequency inventory tags. Monthly sales for a seven-month period were as follows:
Month
|
Sales
|
|
(units)
|
Feb
|
19
|
Mar
|
18
|
Apr
|
17
|
May
|
20
|
Jun
|
19
|
Jul
|
22
|
Aug
|
20
|
- Forecast September sales volume using the naïve approach.
- Forecast September sales volume using a linear equation. a=17.43, b = 0.46.
- Forecast September sales volume using a five-month moving average
- Forecast September sales volume using a weighted average using .60 for August, .30 for July, and .10 for June.
- Forecast September sales volume using Exponential smoothing with a smoothing constant equal to .20, assuming a March forecast of 19.
2, A dry cleaner uses exponential smoothing to forecast equipment usage at its main plant. August usage was forecast to be 88 percent of capacity; actual usage was 89.6 percent of capacity. A smoothing constant (Alpha) of .2 is used.
a.Prepare a forecast for September.
b. Assuming actual September usage of 92 percent, prepare a forecast for October usage.
3. A cosmetics manufacturer's marketing department has developed a linear trend equation that can be used to predict annual sales of its popular Hand & Foot Cream.
Ft =80+14t
Where
Ft Annual forecast in sales (bottles)
t= 0 corresponds to 1990
a. Predict annual sales for the year 2006 using the equation.
4.The manager of 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
|
129
|
124
|
2
|
194
|
200
|
3
|
156
|
150
|
4
|
91
|
94
|
5
|
85
|
80
|
6
|
132
|
140
|
7
|
126
|
128
|
8
|
126
|
124
|
9
|
95
|
100
|
10
|
149
|
150
|
a. Compute MAD for the 5th period
b. Compute MAPE for the 10th period