Business Statistics: A First Course (7th Edition)
7th Edition
ISBN: 9780321979018
Author: David M. Levine, Kathryn A. Szabat, David F. Stephan
Publisher: PEARSON
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Textbook Question
Chapter 3, Problem 3.70CRP
311 is Chicago’s web and phone portal for government information and nonemergency services 311 serves as a comprehensive one-stop shop for residents, visitors, and business owners: therefore, it is critical that 311 representatives answer calls and respond to requests in a timely and accurate fashion. The target response time for answering 311 calls is 45 seconds. Agent abandonment rate is one of several call center metrics tracked by 311 Officials. This metric tracks the percentage ff callers who hang up after the target response time of 45 seconds has elapsed. The file 311CALLCENTER contains the agent abandonment rate for 22 weeks of call center operation during the 7:00 P.M. shift.
- Calculate the
mean ,median , firstquartile , and third quartile. - Calculate the
range ,interquartile range . Variance, standard deviation, and of variation. - Construct a boxplot. Are the data skewed? If so, how?
- Calculate the
correlation coefficient between day and agent abandonment rate. - Based on the results of (a) through (c), what conclusions might you reach concerning 311 call center performance operation?
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A222222222222233
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Table 2: Crack Experiment for Exercise 2
A B C D Treatment Combination
(1)
Replicate
I II
7.037
6.376
14.707 15.219
|++++ 1
བྱ॰༤༠སྦྱོ སྦྱོཋཏྟཱུ
a
b
ab
11.635 12.089
17.273 17.815
с
ас
10.403 10.151
4.368 4.098
bc
abc
9.360 9.253
13.440 12.923
d
8.561 8.951
ad
16.867 17.052
bd
13.876 13.658
abd
19.824 19.639
cd
11.846 12.337
acd
6.125
5.904
bcd
11.190 10.935
abcd
15.653 15.053
Question 3
Continuation of Exercise 2. One of the variables in the experiment described in Exercise 2, heat treatment
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(b) Generate appropriate response surface contour plots for the two regression models in part (a).
(c) What set of conditions would you recommend for the factors A, B, and D if you use heat treatment method
C = +?
(d) Repeat…
Chapter 3 Solutions
Business Statistics: A First Course (7th Edition)
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