Here are the actual tabulated demands for an item for a nine-month period (January through September). Your supervisor wants to test two forecasting methods to see which method was better over this period.

MONTH ACTUAL MONTH ACTUAL January February March April 110 130 150 170 June July August September 180 140 130 140 May 160

a. Forecast April through September using a three-month moving average.

b. Use simple exponential smoothing with an alpha of .3 to estimate April through September.

c. Use MAD to decide which method produced the better forecast over the six-month period.