Operations Management: Processes and Supply Chains (12th Edition) (What's New in Operations Management)
12th Edition
ISBN: 9780134741062
Author: Lee J. Krajewski, Manoj K. Malhotra, Larry P. Ritzman
Publisher: PEARSON
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Textbook Question
Chapter 8, Problem 7P
Sales for the past 12 months at Computer Success are given here. 
- Use a 3-month moving average to
forecast the sales for the months May through December. - Use a 4-month moving average to forecast the sales for the months May through December.
- Compare the performance of the two methods by using the mean absolute deviation as the performance criterion. Which method would you recommend?
- Compare the performance of the two methods by using the mean absolute percent error as the performance criterion. Which method would you recommend?
- Compare the performance of the two method by using the mean squared error as the performance criterion. Which method would you recommend?
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Students have asked these similar questions
The table below shows the sales figures for a brand of shoe over the last 12 months.
Months
Sales
January
69
February
75
March
86
April
92
May
95
June
100
July
108
August
115
September
125
October
131
November
140
December
150
Using the following, forecast the sales for the months up to January the following year:-
1. A simple three-month moving average.
2. A three-period weighted moving average using weights of 1, 2, and 3. Assign the highest weight to the most recent data.
3. Exponential Smoothing when α= .6 and the forecast for March is 350.
4. Determine which of the three forecasting techniques is the most accurate using MAD.
The classified department of a monthly magazine has used a combination of quantitative and qualitative methods to forecast sales of advertising space. Results over a 20-month period are as follows:Month Error1 −8 2 −2 3 4 4 7 5 9 6 5 7 0 8 −3 9 −9 10 −4 11 1
12 6 13 8 14 4 15 1 16 −2 17 −4 18 −8 19 −5 20 −1 a. Compute a tracking signal for months 11 through 20. Compute an initial value of MAD for month 11, and then update it for each month using exponential smoothing with α = .1. What can you conclude? Assume limits of ± 4.b. Using the first half of the data, construct a control chart with 2s limits. What can you conclude?c. Plot the last 10 errors on the control chart. Are the errors random? What is the implication of this?
Interpret the coefficients of your regression model. Specifically, what does the fixed component of the model mean to the consulting firm?
Interpret the fixed term,
b 0b0,
if appropriate. Choose the correct answer below.
A.
It is not appropriate to interpret
b 0b0,
because its value is the predicted billable hours for overhead costs of 0 dollars, but the firm cannot have overhead costs of 0 dollars associated with a client.
B.
The value of
b 0b0
is the predicted overhead costs for 0 billable hours.
C.
It is not appropriate to interpret
b 0b0,
because its value is the predicted overhead costs for 0 billable hours, but someone with 0 billable hours would not actually be a client of the firm.
D.
For each increase of 1 unit in billable hours, the predicted overhead costs are estimated to increase by
b 0b0.
E.
The value of
b 0b0
is the predicted billable hours for an overhead cost of 0 dollars.
F.
For each increase of 1 unit in…
Chapter 8 Solutions
Operations Management: Processes and Supply Chains (12th Edition) (What's New in Operations Management)
Ch. 8 - Figure 8.9 shows summer air visibility...Ch. 8 - Kay and Michael Passe publish What‘s...Ch. 8 - Demand for oil changes at Garcia’s Garage has...Ch. 8 - Prob. 2PCh. 8 - Ohio Swiss Milk Products manufactures and...Ch. 8 - A manufacturing firm has developed a skills test,...Ch. 8 - The materials handling manager of a manufacturing...Ch. 8 - Marianne Kramer, the owner of Handy Man Rentals,...Ch. 8 - Sales for the past 12 months at Computer Success...Ch. 8 - Bradley’s Copiers sells and repairs photocopy...
Ch. 8 - Consider the sales data for Computer Success given...Ch. 8 - A convenience store recently started to carry a...Ch. 8 - Community Federal Bank in Dothan, Alabama,...Ch. 8 - The number of heart surgeries performed at...Ch. 8 - The following data are for calculator sales in...Ch. 8 - Prob. 14PCh. 8 - Forrest and Dan make boxes of chocolates for which...Ch. 8 - The manager of Alaina’s Garden Center must make...Ch. 8 - The manager of a utility company in the Texas...Ch. 8 - Franklin Tooling, Inc., manufactures specialty...Ch. 8 - Create an Excel spreadsheet on your own that can...Ch. 8 - Prob. 20PCh. 8 - Using the data in Problem 20 and the Time-Series...Ch. 8 - Prob. 22PCh. 8 - Cannister, Inc., specializes in the manufacture of...Ch. 8 - The Midwest Computer Company serves a large number...Ch. 8 - A certain food item at P=0.20 (with a combination...Ch. 8 - Prob. 26PCh. 8 - Prob. 27PCh. 8 - A manufacturing firm seeks to develop a better...Ch. 8 - How much does the forecasting process at Deckers...Ch. 8 - Prob. 2VCCh. 8 - What factors make forecasting at Deckers...Ch. 8 - Prob. 4VCCh. 8 - Prob. 5VCCh. 8 - Comment on the forecasting system being used by...Ch. 8 - Develop your own forecast for bow rakes for each...
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