Chapter 5    Demand Forecasting                                                              163
3. Why is demand forecasting important for effective supply chain management?
         4. Explain the impact of a mismatch in supply and demand. What strategies can com-
            panies adopt to influence demand?
         5. What are qualitative forecasting techniques? When are these methods more suitable?
         6. What are the main components of a time series?
         7. Explain the difference between a time series model and an associative model. Under
            what conditions would one model be preferred to the other?
         8. What is the impact of the smoothing constant value on the simple exponential
            smoothing forecast?
         9. Compare and contrast the jury of executive opinion and the Delphi techniques.
        10. Explain the key differences between the weighted moving average and the simple
            exponential smoothing forecasting methods.
        11. What are three measures of forecasting accuracy?
        12. What is a tracking signal? What information does the tracking signal provide that
            managers can use to improve the quality of forecasts?
        13. What are the key features of CPFR? Why would a company consider adopting CPFR?
        14. What are the eight tasks associated with the CPFR model? Why is sharing data
            important in CPFR implementation? What are the benefits of sharing information?
        15. West Marine identified the ten performance improvement steps in their successful
            implementation of CPFR. Is West Marine’s approach unique, or can their experience
            be duplicated at another company? What are the key challenges that other companies
            will face in implementing CPFR?
        16. Why is widespread adoption of CPFR below expectations?
        17. What is cloud computing, and how can companies benefit from this technology in
            solving their supply chain forecasting problems?
        SPREADSHEET PROBLEMS
         1. Ms. Winnie Lin’s company sells computers. Monthly sales for a six-month period are
            as follows:
                                          MONTH      SALES
                                          Jan        18,000
                                          Feb        22,000
                                          Mar        16,000
                                          Apr        18,000
                                          May        20,000
                                          Jun        24,000
           a. Plot the monthly data on a sheet of graph paper.
           b. Compute the sales forecast for July using the following approaches: (1) a four-month
              moving average; (2) a weighted three-month moving average using .50 for June, .30
              for May and .20 for April; (3) a linear trend equation (4) exponential smoothing
              with α (smoothing constant) equal to .40, assuming a February forecast of 18,000
c. Which method do you think is the least appropriate? Why?
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Part 3
         Operations Issues in Supply Chain Management
          2. The owner of the Chocolate Outlet Store wants to forecast chocolate demand.
             Demand for the preceding four years is shown in the following table:
                                              YEAR      DEMAND (POUNDS)
                                                1           68,800
                                                2           71,000
                                                3           75,500
                                                4           71,200
             Forecast demand for Year 5 using the following approaches: (1) a three-year moving
             average; (2) a three-year weighted moving average using .40 for Year 4, .20 for Year 3
             and .40 for Year 2; (3) exponential smoothing with α = .30, and assuming the fore-
             cast for Period 1 = 68,000.
          3. The forecasts generated by two forecasting methods and actual sales are as follows:
                         MONTH               SALES       FORECAST 1       FORECAST 2
                            1                 269           275              268
                            2                 289           266              287
                            3                 294           290              292
                            4                 278           284              298
                            5                 268           270              274
                            6                 269           268              270
                            7                 260           261              259
                            8                 275           271              275
             Compute the MSE, the MAD, the MAPE, the RSFE and the tracking signal for each
             forecasting method. Which method is better? Why?