The operations manager is comparing a 3-week simple moving average with a 5-week simple moving average over 30 weeks. She wants to know which method produced more accurate forecasts, so she subtracts the forecast of the 5-week method from the 3-week method, takes the absolute value of the difference, sums the absolute differences, and divides by 30. What error has she made?

Group of answer choices

-MADs must be calculated separately for the 3- and 5-week moving averages.

-No errors were made; the calculations are correct

-The MSE would be a better choice to compare accuracy than the MAD

-Thirty is an inadequate number of time periods to determine the accuracy of the forecasts

-The 3-week data should have been subtracted from the 5-week data