Sales of industrial vacuum cleaners at R. Lowenthal Supply Co. over the past 13 months are as follows:
(a) Using a moving average with three periods,determine the demand for vacuum cleaners fornext February.
(b) Using a weighted moving average with threeperiods, determine the demand for vacuumcleaners for February. Use 3, 2, and 1 for theweights of the most recent, second most recent,and third most recent periods, respectively. Forexample, if you were forecasting the demandfor February, November would have a weightof 1, December would have a weight of 2, andJanuary would have a weight of 3.
(c) Evaluate the accuracy of each of these methods.
(d) What other factors might R. Lowenthal considerin forecasting sales?