OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
7th Edition
ISBN: 9780077835439
Author: Roger G Schroeder, M. Johnny Rungtusanatham, Susan Meyer Goldstein
Publisher: McGraw-Hill Education
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Chapter 10.S, Problem 1P
Ace Hardware sells spare parts for lawn mowers. The following data were collected for one week in May when replacement lawn-mower blades were in high demand:
| Day | Demand |
| 1 | 10 |
| 2 | 12 |
| 3 | 13 |
| 4 | 15 |
| 5 | 17 |
| 6 | 20 |
| 7 | 21 |
- a. Simulate a
forecast for the week, starting with F1 = 10. T0 = 2, α = .2, and β = .4. Use the trend model given in the chapter supplement. - b. Compute the MAD and tracking signal for the data. Use MADo = 0
- c. Are the MAD and tracking signal within tolerances?
- d. Simulate a forecast using simple smoothing for the week, starting with F1 = 10 and α = .2. Plot the forecast and the demand on a graph. Note how the forecast lags behind demand.
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1. Forecasting stationary series
The company Handy Inc. produces a solar-powered electronic calculator that has experienced the following monthly sales history for the first four months of the year (in thousands of units):
January February. March. April
sales 23.3. 72.3. 30,3. 15.5
a) Find the forecast for May using the Moving Averages method with N = 3.
b) Assume that the forecast for January was 25. Determine the one-step ahead forecast for February through May, using exponential smoothing with a smoothing constant of α = 0.15.
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d) Compare the MAD (Mean Absolute Deviation) and MSE (Mean Squared Error) for the forecast for February to April in problems b and c. Comment the accuracy of the forecasts.
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2. Regression analysis
3 000 000
2 500 000
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Sarah has been custom manufacturing sweaters now for 7 years. Her annual sales are shown below.
Year
Sales
1
178
2
215
3
233
4
301
5
337
6
330
7
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What are her forecasted sales for year 8 using a 5 year weighted average where w1=.4, w2=.3, w3=.15, w4=.1, w5=.05?
What are her forecasted sales for year 8 using exponential smoothing? Assume year 7 forecast was 323. Select your own alpha.
Which forecast method is the best for Sarah to use based on MAD? Why?
Chapter 10 Solutions
OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
Ch. 10.S - Ace Hardware sells spare parts for lawn mowers....Ch. 10.S - eXcel The daily demand for chocolate donuts from...Ch. 10.S - The SureGrip Tire Company produces tires of...Ch. 10.S - eXcelManagement believes there is a seasonal...Ch. 10.S - Management of the ABC Floral Shop believes that...Ch. 10 - Prob. 1DQCh. 10 - What is the distinction between forecasting and...Ch. 10 - Qualitative forecasting methods should be used...Ch. 10 - Describe the uses of qualitative, time-series, and...Ch. 10 - Qualitative forecasts and causal forecasts are not...
Ch. 10 - Prob. 6DQCh. 10 - What are the advantages of exponential smoothing...Ch. 10 - How should the choice of be made for exponential...Ch. 10 - Prob. 9DQCh. 10 - Prob. 10DQCh. 10 - Explain how CPFR can be used to reduce forecasting...Ch. 10 - Under what circumstances might CPFR be useful, and...Ch. 10 - Daily demand for marigold flowers at a large...Ch. 10 - The number of daily calls for the repair of Speedy...Ch. 10 - 3-The ABC Floral Shop sold the following number of...Ch. 10 - The Handy Dandy Department Store had forecast...Ch. 10 - 5-The Yummy Ice Cream Company uses the exponential...Ch. 10 - Using the data in problem 2, prepare exponentially...Ch. 10 - Compute the errors of bias and absolute deviation...Ch. 10 - eXcel At the ABC Floral Shop, an argument...Ch. 10 - Only a portion of the following table for...Ch. 10 - A candy store has sold the following number of...Ch. 10 - eXcel A grocery store sells the following number...Ch. 10 - Prob. 12PCh. 10 - The Easyfit tire store had demand for tires shown...Ch. 10 - Prob. 14P
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