Reconsider Prob. 27.7-4. Ben Swanson now has decided to use the exponential smoothing method to forecast future sales of washing machines, but he needs to decide on which smoothing constant to use. Using an initial estimate of 24, apply this method retrospectively to the 12 months of last year with α = 0.1, 0.2, 0.3, 0.4, and 0.5.
(a) Compare MAD for these five values of the smoothing constant α.
(b) Calculate and compare MSE for these five values of α.
In Problem 27.7-4

Month Sales Month SalesMonth Sales January 22 September 21 May Febary 24 June 22 July 23 27 October March April 29 20 November 23 28 August 26 December 28