A manufacturing firm seeks to develop a better forecast for an important product, and believes that there is a trend to the data. OM Explorer€™s Trend Projection with Regression Solver has been set up with the 47 demands in the history file. Note the €œLoad Problem 26 Data€ button in the Trend Projection with Regression Solver that when clicked will automatically input the demand data. Otherwise, you can enter the demand data directly into the Inputs sheet.

a. What is your forecast for December of Year 4, making period 1 as the starting period for the regression?
b. The actual demand for period 48 was just learned to be 5,100. Add this demand to the Inputs file and change the starting period for the regression to period 2 so that the number of periods in the regression remains unchanged. How much or little does the forecast for period 49 change from the one for period 48? The error measures? Are you surprised?
c. Now change the time when the regression starts to period 25 and repeat the process. What differences do you note now? What forecast will you make for period49?

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