Here are the errors associated with a particular forecast over the past five months, in chronological order: 2, 5, 0, -5, -10. Which of the following statements is (are) true? I. The forecast was too high during the fifth month. II. The mean error over these five months is -2. III. The forecast was perfectly accurate during one of the months. O a. I only Ob.Il only Oc. Il only O d. I and II O e. I, Il and II

Here are the errors associated with a particular forecast over the past five months, in chronological order: 2, 5, 0, -5, -10. Which of the following statements is (are) true? I. The forecast was too high during the fifth month. II. The mean error over these five months is -2. III. The forecast was perfectly accurate during one of the months. O a. I only Ob.Il only Oc. Il only O d. I and II O e. I, Il and II

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter13: Regression And Forecasting Models

Section13.6: Moving Averages Models

Problem 19P: The file P13_19.xlsx contains the weekly sales of a particular brand of paper towels at a...

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The file P13_42.xlsx contains monthly data on consumer revolving credit (in millions of dollars) through credit unions. a. Use these data to forecast consumer revolving credit through credit unions for the next 12 months. Do it in two ways. First, fit an exponential trend to the series. Second, use Holts method with optimized smoothing constants. b. Which of these two methods appears to provide the best forecasts? Answer by comparing their MAPE values.
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The Baker Company wants to develop a budget to predict how overhead costs vary with activity levels. Management is trying to decide whether direct labor hours (DLH) or units produced is the better measure of activity for the firm. Monthly data for the preceding 24 months appear in the file P13_40.xlsx. Use regression analysis to determine which measure, DLH or Units (or both), should be used for the budget. How would the regression equation be used to obtain the budget for the firms overhead costs?
The file P13_26.xlsx contains the monthly number of airline tickets sold by the CareFree Travel Agency. a. Create a time series chart of the data. Based on what you see, which of the exponential smoothing models do you think will provide the best forecasting model? Why? b. Use simple exponential smoothing to forecast these data, using a smoothing constant of 0.1. c. Repeat part b, but search for the smoothing constant that makes RMSE as small as possible. Does it make much of an improvement over the model in part b?
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