a. Plot the monthly sales data. Do you observe any trend, cycles or random variations? b. Forecast January sales using each of the following: a. Naïve method b. A 3-month moving average c. A 6-month weighted moving average using 0.1, 0.1, 0.1, 0.2, 0.2 and 0.3 with the heaviest weights applied to the most recent months d. Exponential smoothing using an x = 0.3 and a September forecast of 18. c. Compute the MAD and MAPE for the naïve method and 3-month moving average.

a. Plot the monthly sales data. Do you observe any trend, cycles or random variations? b. Forecast January sales using each of the following: a. Naïve method b. A 3-month moving average c. A 6-month weighted moving average using 0.1, 0.1, 0.1, 0.2, 0.2 and 0.3 with the heaviest weights applied to the most recent months d. Exponential smoothing using an x = 0.3 and a September forecast of 18. c. Compute the MAD and MAPE for the naïve method and 3-month moving average.

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 22P: The file P13_22.xlsx contains total monthly U.S. retail sales data. While holding out the final six...

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