Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card)
6th Edition
ISBN: 9780357228708
Author: David R. Anderson; Dennis J. Sweeney; Thomas A. Williams
Publisher: Cengage Learning US
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 9.6, Problem 46E
A large department of the Federal Government wants to determine whether the average number of business emails sent and received per business day by its employees differs from the average number of emails sent and received per day by corporate employees. Suppose the department electronically collects information on the number of business emails sent and received on a randomly selected business day over the past year from each of 10,163 randomly selected federal employees. The results are provided in the DATAfile named FedEmail. Assuming that the standard deviation of the number of emails sent and received by this department’s employees is σ = 25 and the average number of emails sent and received per day by corporate employees is 101.5, test the department’s hypothesis at α = .01. Discuss the practical significance of the results.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Question 2
A nickel-titanium alloy is used to make components for jet turbine aircraft engines. Cracking is a potentially
serious problem in the final part because it can lead to nonrecoverable failure. A test is run at the parts producer
to determine the effect of four factors on cracks. The four factors are: pouring temperature (A), titanium content
(B), heat treatment method (C), amount of grain refiner used (D). Two replicates of a 24 design are run, and
the length of crack (in mm x10-2) induced in a sample coupon subjected to a standard test is measured. The
data are shown in Table 2.
1
(a) Estimate the factor effects. Which factor effects appear to be large?
(b) Conduct an analysis of variance. Do any of the factors affect cracking? Use a = 0.05.
(c) Write down a regression model that can be used to predict crack length as a function of the significant
main effects and interactions you have identified in part (b).
(d) Analyze the residuals from this experiment.
(e) Is there an…
A 24-1 design has been used to investigate the effect of four factors on the resistivity of a silicon wafer. The data
from this experiment are shown in Table 4.
Table 4: Resistivity Experiment for Exercise 5
Run
A
B
с
D
Resistivity
1
23
2
3
4
5
6
7
8
9
10
11
12
I+I+I+I+Oooo
0
0
||++TI++o000
33.2
4.6
31.2
9.6
40.6
162.4
39.4
158.6
63.4
62.6
58.7
0
0
60.9
3
(a) Estimate the factor effects. Plot the effect estimates on a normal probability scale.
(b) Identify a tentative model for this process. Fit the model and test for curvature.
(c) Plot the residuals from the model in part (b) versus the predicted resistivity. Is there any indication on
this plot of model inadequacy?
(d) Construct a normal probability plot of the residuals. Is there any reason to doubt the validity of the
normality assumption?
Stem1: 1,4
Stem 2: 2,4,8
Stem3: 2,4
Stem4: 0,1,6,8
Stem5: 0,1,2,3,9
Stem 6: 2,2
What’s the Min,Q1, Med,Q3,Max?
Chapter 9 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card)
Ch. 9.1 - 1. The manager of the Danvers-Hilton Resort Hotel...Ch. 9.1 - 2. The manager of an automobile dealership is...Ch. 9.1 - 3. A production line operation is designed to fill...Ch. 9.1 - 4. Because of high production-changeover time and...Ch. 9.2 - 5. Duke Energy reported that the cost of...Ch. 9.2 - Prob. 6ECh. 9.2 - Carpet Salesperson Salaries. Carpetland...Ch. 9.2 - 8. Suppose a new production method will be...Ch. 9.3 - Consider the following hypothesis test:
A sample...Ch. 9.3 - Prob. 10E
Ch. 9.3 - Consider the following hypothesis test:
A sample...Ch. 9.3 - Prob. 12ECh. 9.3 - Prob. 13ECh. 9.3 - Prob. 14ECh. 9.3 - Federal Tax Returns. According to the IRS,...Ch. 9.3 - In a study entitled How Undergraduate Students Use...Ch. 9.3 - The mean hourly wage for employees in...Ch. 9.3 - Young millennials, adults aged 18 to 34, are...Ch. 9.3 - The Internal Revenue Service (IRS) provides a...Ch. 9.3 - Prescription Drug Costs. Annual expenditure for...Ch. 9.3 - Cost of Telephone Surveys. Fowle Marketing...Ch. 9.3 - Time in Supermarket Checkout Lines. CCN and...Ch. 9.4 - Consider the following hypothesis test:
A sample...Ch. 9.4 - Consider the following hypothesis test:
A sample...Ch. 9.4 - Consider the following hypothesis test:
A sample...Ch. 9.4 - Prob. 26ECh. 9.4 - Which is cheaper: eating out or dining in? The...Ch. 9.4 - CEO Tenure. A shareholders’ group, in lodging a...Ch. 9.4 - The national mean annual salary for a school...Ch. 9.4 - Time in Child Care. The time married men with...Ch. 9.4 - Chocolate Consumption. The United States ranks...Ch. 9.4 - Used Car Prices. According to the National...Ch. 9.4 - Automobile Insurance Premiums. The Onsure.com...Ch. 9.4 - Prob. 34ECh. 9.5 - Consider the following hypothesis test:
A sample...Ch. 9.5 - Prob. 36ECh. 9.5 - The U.S. Bureau of Labor Statistics reports that...Ch. 9.5 - Attitudes toward Supermarket Brands. A study by...Ch. 9.5 - Prob. 39ECh. 9.5 - Prob. 40ECh. 9.5 - Ten years ago 53% of American families owned...Ch. 9.5 - Returned Merchandise. According to the University...Ch. 9.5 - Prob. 43ECh. 9.5 - Prob. 44ECh. 9.5 - The American Association of Individual Investors...Ch. 9.6 - A large department of the Federal Government wants...Ch. 9.6 - CEOs who belong to a popular business-oriented...Ch. 9.6 - Prob. 48ECh. 9.6 - Prob. 49ECh. 9 - Production Line Fill Weights. A production line...Ch. 9 - Scholarship Examination Scores. At Western...Ch. 9 - Exposure to Background Television. CNN reports...Ch. 9 - The Wall Street Journal reported that bachelor’s...Ch. 9 - Data from the Office for National Statistics show...Ch. 9 - The mean time to earn a bachelor’s degree is 5.8...Ch. 9 - Prob. 56SECh. 9 - In Hamilton County, Ohio, the mean number of days...Ch. 9 - Fifty-two percent of Americans report that they...Ch. 9 - Prob. 59SECh. 9 - Prob. 60SECh. 9 - The unemployment rate for 18- to 34-year-olds was...Ch. 9 - Prob. 62SECh. 9 - In recent years more people have been working past...Ch. 9 - Case Problem 1 Quality Associates, Inc.
Quality...Ch. 9 - Case problem 2 Ethical Behavior of Business...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- Are the t-statistics here greater than 1.96? What do you conclude? colgPA= 1.39+0.412 hsGPA (.33) (0.094) Find the P valuearrow_forwardA poll before the elections showed that in a given sample 79% of people vote for candidate C. How many people should be interviewed so that the pollsters can be 99% sure that from 75% to 83% of the population will vote for candidate C? Round your answer to the whole number.arrow_forwardSuppose a random sample of 459 married couples found that 307 had two or more personality preferences in common. In another random sample of 471 married couples, it was found that only 31 had no preferences in common. Let p1 be the population proportion of all married couples who have two or more personality preferences in common. Let p2 be the population proportion of all married couples who have no personality preferences in common. Find a95% confidence interval for . Round your answer to three decimal places.arrow_forward
- A history teacher interviewed a random sample of 80 students about their preferences in learning activities outside of school and whether they are considering watching a historical movie at the cinema. 69 answered that they would like to go to the cinema. Let p represent the proportion of students who want to watch a historical movie. Determine the maximal margin of error. Use α = 0.05. Round your answer to three decimal places. arrow_forwardA random sample of medical files is used to estimate the proportion p of all people who have blood type B. If you have no preliminary estimate for p, how many medical files should you include in a random sample in order to be 99% sure that the point estimate will be within a distance of 0.07 from p? Round your answer to the next higher whole number.arrow_forwardA clinical study is designed to assess the average length of hospital stay of patients who underwent surgery. A preliminary study of a random sample of 70 surgery patients’ records showed that the standard deviation of the lengths of stay of all surgery patients is 7.5 days. How large should a sample to estimate the desired mean to within 1 day at 95% confidence? Round your answer to the whole number.arrow_forward
- A clinical study is designed to assess the average length of hospital stay of patients who underwent surgery. A preliminary study of a random sample of 70 surgery patients’ records showed that the standard deviation of the lengths of stay of all surgery patients is 7.5 days. How large should a sample to estimate the desired mean to within 1 day at 95% confidence? Round your answer to the whole number.arrow_forwardIn the experiment a sample of subjects is drawn of people who have an elbow surgery. Each of the people included in the sample was interviewed about their health status and measurements were taken before and after surgery. Are the measurements before and after the operation independent or dependent samples?arrow_forwardiid 1. The CLT provides an approximate sampling distribution for the arithmetic average Ỹ of a random sample Y₁, . . ., Yn f(y). The parameters of the approximate sampling distribution depend on the mean and variance of the underlying random variables (i.e., the population mean and variance). The approximation can be written to emphasize this, using the expec- tation and variance of one of the random variables in the sample instead of the parameters μ, 02: YNEY, · (1 (EY,, varyi n For the following population distributions f, write the approximate distribution of the sample mean. (a) Exponential with rate ẞ: f(y) = ß exp{−ßy} 1 (b) Chi-square with degrees of freedom: f(y) = ( 4 ) 2 y = exp { — ½/ } г( (c) Poisson with rate λ: P(Y = y) = exp(-\} > y! y²arrow_forward
- 2. Let Y₁,……., Y be a random sample with common mean μ and common variance σ². Use the CLT to write an expression approximating the CDF P(Ỹ ≤ x) in terms of µ, σ² and n, and the standard normal CDF Fz(·).arrow_forwardmatharrow_forwardCompute the median of the following data. 32, 41, 36, 42, 29, 30, 40, 22, 25, 37arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Hypothesis Testing using Confidence Interval Approach; Author: BUM2413 Applied Statistics UMP;https://www.youtube.com/watch?v=Hq1l3e9pLyY;License: Standard YouTube License, CC-BY
Hypothesis Testing - Difference of Two Means - Student's -Distribution & Normal Distribution; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=UcZwyzwWU7o;License: Standard Youtube License