4.

In this problem, you are to test the validity of your forecasting model. Here are the forecasts for a model you have been using and the actual demands that occurred:

WEEK	FORECAST	ACTUAL
1	830	915
2	865	1,015
3	965	1,050
4	965	925
5	1,015	930
6	1,010	1,025

a. Use the method stated in the text to compute the MAD and tracking signal for each week. (Negative values should be indicated by a minus sign. Round your "Tracking Signal" to 1 decimal place and all other answers to the nearest whole number.)

b. Decide whether the forecasting model you have been using is giving reasonable results.

- The forecasting model is unacceptable

- The forecasting model is acceptable

16. A company wants to forecast demand using the weighted moving average. If the company uses three prior yearly sales values (i.e., year 2017 = 160, year 2018 = 140, and year 2019 = 170), and we want to weight year 2014 at 30 percent, year 2018 at 30 percent, and year 2019 at 40 percent, which of the following is the weighted moving average forecast for year 2020?

• 152

• 170

• 158

• 146

• 168

19. A company wants to forecast demand using the simple moving average. If the company uses three prior yearly sales values (i.e., year 2017 = 130, year 2018 = 110, and year 2019 = 160), which of the following is the simple moving average forecast for year 2020?

• 122.5

• 139.3

• 100.5

• 133.3

• 135.6

Week Forecast Actual Deviation Running Sum of Forecast Errors Absolute Deviation Sum of Absolute Deviation Mean Absolute Deviation Tracking Signal 1 830 915 2 2 865 1,015 3 965 1,050 4 965 925 5 1,015 930 6 1,010 1,025