Problem 15-08 (Algorithmic) Refer again to the gasoline sales time series data i

Question

Problem 15-08 (Algorithmic)

Refer again to the gasoline sales time series data in the following table.

Using a weight of 1/2 for the most recent observation, 1/3 for the second most recent, and 1/6 for third most recent, compute a three-week weighted moving average for the time series. Use rounded for two decimal places values for intermediate colculations.

Compute the MSE for the weighted moving average in part a. Do you prefer this weighted moving average to the unweighted moving average? Remember that the MSE for the unweighted moving average is 10.22. Round your answer to two decimal places.

MSE =

Week Sales (1000s of gallons) 1 18 2 24 3 20 4 24 5 20 6 14 7 20 8 17 9 25 10 21 11 16 12 24

Explanation / Answer

MSE= 209.81/9=23.31

MSE of unweighted moving average is lower than weighted moving average so unweighted moving average is preferable.

Week Sales Weighted Moving
Average Forecast Forecast Error Error 2 1 18 - - - 2 24 - - - 3 20 - - - 4 24 21 3 9 5 20 22.67 -2.67 7.13 6 14 22.67 -8.67 75.17 7 20 17.67 2.33 5.43 8 17 18 -1 1 9 25 17.5 7.5 56.25 10 21 21.5 -0.5 0.25 11 16 21.67 -5.67 32.15 12 24 19.16 4.84 23.43 Total 209.81

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---