Question

Two independent methods of forecasting based on judgment and experience have been prepared each month for the past 10 months. The forecasts and actual sales are as follows:

Month	Sales	Forecast 1	Forecast 2
1	771	770	768
2	790	788	787
3	794	798	798
4	776	774	773
5	772	771	773
6	770	769	770
7	761	765	764
8	774	777	778
9	792	794	792
10	794	791	791

a. Compute a tracking signal for the 10th month for each forecast using the cumulative error for months 1 to 10. Use action limits of ± 4. Is there bias present? (Do not round your intermediate calculations. Round your answers to 2 decimal places. Negative amounts should be indicated by a minus sign.)

Forecast	Tracking Signal	Bias
Method 1		(Click to select)  Not present  Present
Method 2		(Click to select)  Not present  Present

b. Compute 2s control limits for each forecast. (Do not round your intermediate calculations. Round your answers to 2 decimal places.)

Forecast	Control Limits
Method 1
Method 2

Answer 1

A ) Compute a tracking signal for the 10th month for each forecast using the cumulative error for months 1 to 10. Use action limits of ± 4. Is there bias present?

ANSWER:

B) Compute 2s control limits for each forecast. (Do not round your intermediate calculations. Round your answers to 2 decimal places.)

ANSWER: