3. [Ch. 4. Business Forecasting Decision Making on Forecasting Models] Alexa is a department manager at a local department store. He took statistics and operations management in college and has recently forecast sales of toasters using a combination of forecasting methods and his expertise/experiences as below:

Based on the forecasting error, Mean Absolute Deviation (MAD) for the manager's forecast and all the other forecasts, which method seems the most accurate method and the least accurate among proposed forecasting approaches? Why? (Please state your reasons using the forecasting errors.) [You dont have to calculate any statistical measures or indexes.]

-44 Unit:1000 Manager's Forecast Nave Forecast 3 Mon. Moving Avg. 3 Mon. Weighted MA. Exp. Smoothing (a=.4) Unit Manager's No. Month Error Error! Nave Error Error 3MA Error Error 3WMA Error Error EXP Error | Error Sales Forecast 1 January 52 62 -10 10 55.00 -3.00 3.00 2 February 61 34 27 27 52 9 9 53.80 7.20 7.20 3 March 73 25 48 48 61 12 12 56.68 16.32 16.32 4 April 45 89 44 73 -28 28 62.00 -17.00 17.00 66.67 -21.67 21.671 63.21 -18.21 18.21 5 May 66 86 -20 20 79 -13 13 59.67 6.33 6.33 56.11 9.89 9.89 55.92 10.08 10.08 6 June 51 34 17 17 66 -15 15 61.33 -10.33 10.33 59.78 -8.78 8.78 59.95 -8.95 8.95 7 July 34 50 -16 16 51 -17 17 54.00-20.00 20.00 55.33 -21.33 21.33 56.37 -22.37 22.37 8 August 44 65 -21 21 47 -3 3 50.33 -6.33 6.33 43.22 0.78 0.78 47.42 -3.42 3.42 9 September 30 52 22 44 -14 14 43.00-13.00 13.00 41.44 -11.44 11.44 46.05 -16.05 16.05 10 October 65 42 23 23 30 35 35 36.00 29.00 29.00 35.11 29.89 29.89 39.63 25.37 25.37 11 November 89 60 29 29 55 34 34 46.33 42.67 42.67 51.00 38.00 38.00 49.78 39.22 39.22 12 December ? 75.00 74.00 61.33 74.44 65.47 SUM 267.00 180.00 144.67 141.78 167.20 -22 n = 11 10 8 8 11 MAD 24.27 18.00 18.08 17.72 15.20