Question

4) The table below shows the monthly sales of laptops at a local branch of a major technology and media retail store. I 1 2 3 4 5 6 8 9 10 11 12 Sales 186 75 72 83 132 65 110 90 67 92 98 73 FMA4) 8926 85.5 8939.1296. 6126819 Fa=0.1 86 a. Determine the one-step-ahead forecast using the four most recent sales figures, MA(4). (Use the table to fill in your answers) 15 points b. Determine the one-step-ahead forecast using exponential smoothing with a smoothing constant of 0.1, a = 0.1. Assume F1 = D1. (Use the table to fill in your answers) 15 points c. Determine the forecast errors for these periods. 15 points d. Compute the MAD, MSE, and BIAS for each of the methods, MA(4) and ES(a=0.1). (Show your equations and your work) 30 points e. Based on just the results from part (d), which of the two forecasting methods should the company use in the future? (circle one) 3 points a. MA(4) b. ES(a=0.1)

Can anyone help me with this question in Production System ?

Answer 1

Answer :- Tul calculating forecast using u-month moving average & Exponential smoothine with d = 011 8- a 7 moving average method CUMA) : - Month Sales forecast Eure irurell Erve a 86 T2 75 72 83 5 132 6 65 [ 110 80 | 67 10 92 Il 98 12 73 113 - 179 90.5 88 1975 | 96.7 7 80.5 18712 8u.2 89.5 I 53-153 8 8 12809 -25.5 25.5 3 650.2. 22 22 22 usu - 17.5 -17.5.18 306.2 1- 29.7 885. I 11.5 11.5 28 132.2 10.7 10.7 1115,6 -11.2 11.2.08 126.6 29.7 T13.25 181. 1 5508.91 JL Bias => [ 13.25 ] a + AV 3 M.A.D=> [181.17 => [aa. 64] 2) MS, E => [5508.9 7 =[688.61] L 8 - One step ahead forecast month (13) = 82.5)

(c b]* Exponential Smoothing <= 0.1 Mouth Sales forecast Euve lessoela Erwe Eis=o.ll 75 72 93 86 86 1 84.9 83.6 183.5 88.3 86.0 88.4 87.6 85.5 86.1 87.3 85,9 -11 1-12,9 1-0.6 Tu8,5 - 23,3 24 1-8.4 - 2006 1219 0.6 usis 23,3 121 I 166.4 0.36 235212 540.9 576 70.6 uzuiu 142:2 lul6 204.5 2u 10. 16.5 814 2016 6.5 llig 14.3 11,9 -14.3 T-0.2 4642.2 182 * N=0.1 Ft = X A++ CL-Q ft = 0.1A.Lt (1 -0.fi Fount 0.9 F... I* Bias = [-0.2] * MAD= [182/11 ] = [16.54] * MSE = [4642. 2 = [422.02] * One-stefa Shand forecast for month 13 3

e) based on the results from part (d), exponential smoothing with Alpha=0.1 is the best method, that the company should use in the future. As it's bias, mean absolute deviation and mean squared error values are smaller than that of calculated with moving average (4month).

Thus, ✓ ES(a=0.1)