Industrial Engineering and Engineering Management Department 0405511: Operations Management Fall 2021 / 2022 Instructor: Dr. Ridvan Aydin Date: 7 th November 2021 Case Study Assignment 2 Due on November 18, 2021 @ 11:59 PM Note: The assignment can be done with 1-2 students. Submit a single Excel file with your solutions and comments. Weekly demand at Cold Ice-cream are as follows: Week Demand 1 80 2 130 3 230 4 340 5 100 6 180 7 230 8 380 9 120 10 130 11 320 12 410 1) [60 Points] Estimate demands for the next four weeks using four-week moving average, simple exponential smoothing with a= 0.2, and linear trend equation methods. Evaluate the MAD, MSE and MAPE for forecasted data in each case. Which methods do you prefer? Why? 2) [40 Points] Using the same data, estimate demand using the trend-adjusted exponential smoothing model with a= 0.15 and =0.25. Evaluate the MAD, MSE and MAPE for forecasted data. Estimate the optimal combination of smoothing constants. Using the optimal smoothing constants, comment which forecasting technique is the most suitable?