Practical Management Science
6th Edition
ISBN: 9781337406659
Author: WINSTON, Wayne L.
Publisher: Cengage,
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Textbook Question
Chapter 13, Problem 34P
A small computer chip manufacturer wants to
- a. Determine an equation that can be used to predict monthly production costs from units produced. Are there any outliers?
- b. How could the regression line obtained in part a be used to determine whether the company was efficient or inefficient during any particular month?
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The following time series represents the number of automobiles sold by a car dealership each of the past five months.
t
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5
Yt
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(a) Construct a time series plot.
What type of pattern exists in the data?
The time series plot shows a linear trend.The time series plot shows a horizontal pattern. The time series plot shows a seasonal pattern.The time series plot shows a nonlinear trend.
(b)
Use simple linear regression analysis to find the parameters for the line that minimizes MSE for this time series.
t =
(c)
What is the forecast for
t = 6?
Create a line graph for this set of monthly sales numbers.
Run a regression analysis.
What is the regression equation?
Is the regression equation significant? How can you tell?
What is the Rsquare? What does this signify?
What is the sales forecast for month 13?
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550
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548
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546
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549
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550
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548
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551
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553
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Click the icon to view the additional data.
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(745)
12
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2
=86.5
More Info
March 2017
April
May
June
July
August
September
October
November
December
January 2018
February
Monthly Sales
5,300
3,990
5,700
6,520
7,600
7,420
Print
6,710
4,870
3,990
3,900
3,320
2,670
Temperature
51
56
Done
64
80
79
87
83
67
58
41
39
40
X
Chapter 13 Solutions
Practical Management Science
Ch. 13.3 - The file P13_01.xlsx contains the monthly number...Ch. 13.3 - The file P13_02.xlsx contains five years of...Ch. 13.3 - The file P13_03.xlsx contains monthly data on...Ch. 13.3 - The file P13_04.xlsx lists the monthly sales for a...Ch. 13.3 - Management of a home appliance store wants to...Ch. 13.3 - Do the sales prices of houses in a given community...Ch. 13.3 - Prob. 7PCh. 13.3 - The management of a technology company is trying...Ch. 13.3 - Prob. 9PCh. 13.3 - Sometimes curvature in a scatterplot can be fit...
Ch. 13.4 - Prob. 12PCh. 13.4 - A trucking company wants to predict the yearly...Ch. 13.4 - An antique collector believes that the price...Ch. 13.4 - Stock market analysts are continually looking for...Ch. 13.4 - Suppose that a regional express delivery service...Ch. 13.4 - The owner of a restaurant in Bloomington, Indiana,...Ch. 13.6 - The file P13_19.xlsx contains the weekly sales of...Ch. 13.6 - The file P13_20.xlsx contains the monthly sales of...Ch. 13.6 - The file P13_21.xlsx contains the weekly sales of...Ch. 13.6 - The file P13_22.xlsx contains total monthly U.S....Ch. 13.7 - You have been assigned to forecast the number of...Ch. 13.7 - Simple exponential smoothing with = 0.3 is being...Ch. 13.7 - The file P13_25.xlsx contains the quarterly...Ch. 13.7 - The file P13_26.xlsx contains the monthly number...Ch. 13.7 - The file P13_27.xlsx contains yearly data on the...Ch. 13.7 - The file P13_28.xlsx contains monthly retail sales...Ch. 13.7 - The file P13_29.xlsx contains monthly time series...Ch. 13.7 - A version of simple exponential smoothing can be...Ch. 13 - Prob. 31PCh. 13 - Prob. 32PCh. 13 - Management of a home appliance store would like to...Ch. 13 - A small computer chip manufacturer wants to...Ch. 13 - The file P13_35.xlsx contains the amount of money...Ch. 13 - Prob. 36PCh. 13 - Prob. 37PCh. 13 - Prob. 39PCh. 13 - The Baker Company wants to develop a budget to...Ch. 13 - Prob. 41PCh. 13 - The file P13_42.xlsx contains monthly data on...Ch. 13 - Prob. 43PCh. 13 - Prob. 44PCh. 13 - Prob. 45PCh. 13 - Prob. 46PCh. 13 - Prob. 49P
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