The monthly market shares of General Electric Company for 12 consecutive months follow. A. Construct a time series plot. What type of pattern exists in the data? B. Develop three-month and four-month moving averages for this time series. Does the three-month or the four-month moving average provide the better forecasts based on MSE? Explain your reasoning. C. Using your results in (B), compute MAD, MAPE, and Tracking Signal (TS). Which method provides better forecast? Explain your reasoning. Assume TS limit of ±4. D. Apply exponential smoothing to the data. Compute MSE, MAPE, MAD, and TS. Use a = 0.3. How does exponential smoothing compare with four-month moving average? Assume TS limit of ±4. Month 1 2 3 4 5 6 7 8 9 SEEL 10 11 12 Market Shares 23.39 23.56 23.02 23.03 23.60 23.37 23.21 23.40 23.31 23.94 23.39 23.50

The monthly market shares of General Electric Company for 12 consecutive months follow. A. Construct a time series plot. What type of pattern exists in the data? B. Develop three-month and four-month moving averages for this time series. Does the three-month or the four-month moving average provide the better forecasts based on MSE? Explain your reasoning. C. Using your results in (B), compute MAD, MAPE, and Tracking Signal (TS). Which method provides better forecast? Explain your reasoning. Assume TS limit of ±4. D. Apply exponential smoothing to the data. Compute MSE, MAPE, MAD, and TS. Use a = 0.3. How does exponential smoothing compare with four-month moving average? Assume TS limit of ±4. Month 1 2 3 4 5 6 7 8 9 SEEL 10 11 12 Market Shares 23.39 23.56 23.02 23.03 23.60 23.37 23.21 23.40 23.31 23.94 23.39 23.50

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter13: Regression And Forecasting Models

Section13.7: Exponential Smoothing Models

Problem 26P: The file P13_26.xlsx contains the monthly number of airline tickets sold by the CareFree Travel...

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