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Applied Statistics and Probability for Engineers
6th Edition
ISBN: 9781118539712
Author: Douglas C. Montgomery
Publisher: WILEY
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Chapter 4.11, Problem 174E
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A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A retail chain is interested in determining whether a digital video point-of-purchase (POP) display would stimulate higher sales for a brand advertised compared to the standard cardboard point-of-purchase display. To test this, a one-shot static group design experiment was conducted over a four-week period in 100 different stores. Fifty stores were randomly assigned to the control treatment (standard display) and the other 50 stores were randomly assigned to the experimental treatment (digital display). Compare the sales of the control group (standard POP) to the experimental group (digital POP).
What were the average sales for the standard POP display (control group)?
What were the sales for the digital display (experimental group)?
What is the (mean) difference in sales between the experimental group and control group?
List the null hypothesis being tested.
Do you reject or retain the null hypothesis based on the results of the independent t-test?
Was the difference between the…
Chapter 4 Solutions
Applied Statistics and Probability for Engineers
Ch. 4.2 - 4-1. Suppose that f(x) = e−x for 0 < x. Determine...Ch. 4.2 - 4-2. Suppose that f (x) = 3(8x – x2)/256 for 0< x...Ch. 4.2 - 4-3. Suppose that f (x) = 0.5 cos x for −π/2 < x <...Ch. 4.2 - Prob. 4ECh. 4.2 - 4-5. Go Tutorial Suppose that for 3 < x < 5....Ch. 4.2 - Prob. 6ECh. 4.2 - 4-7. Suppose that f(x) = 1 .5x2 for −1 < x < 1....Ch. 4.2 - 4-8. The probability density function of the time...Ch. 4.2 - 4-9. The probability density function of the net...Ch. 4.2 - Prob. 10E
Ch. 4.2 - 4-11. The probability density function of the...Ch. 4.2 - Prob. 12ECh. 4.2 - 4-13. A test instrument needs to be calibrated...Ch. 4.2 - Prob. 15ECh. 4.2 - Prob. 16ECh. 4.3 - 4-17. Suppose that the cumulative distribution...Ch. 4.3 - 4-18. Suppose that the cumulative distribution...Ch. 4.3 - 4-19. Determine the cumulative distribution...Ch. 4.3 - Prob. 20ECh. 4.3 - 4-21. Determine the cumulative distribution...Ch. 4.3 - Prob. 22ECh. 4.3 - Prob. 23ECh. 4.3 - 4-24. Determine the cumulative distribution...Ch. 4.3 - 4-25. Determine the cumulative distribution...Ch. 4.3 - 4-26. The probability density function of the time...Ch. 4.3 - 4-27. The gap width is an important property of a...Ch. 4.3 - Determine the probability density function for...Ch. 4.3 - Determine the probability density function for...Ch. 4.3 - Prob. 30ECh. 4.3 - Prob. 31ECh. 4.3 - Prob. 33ECh. 4.4 - 4-35. Suppose that f(x) = 0.25 for 0 < x < 4....Ch. 4.4 - 4-36. Suppose that f(x) = 0.125x for 0 < x < 4....Ch. 4.4 - 4-37. Suppose that f(x) = 1.5x2 for −1< x < 1....Ch. 4.4 - Prob. 38ECh. 4.4 - Prob. 39ECh. 4.4 - Prob. 40ECh. 4.4 - Prob. 41ECh. 4.4 - 4.42 Determine the mean and variance of the random...Ch. 4.4 - Prob. 43ECh. 4.4 - 4-45. Suppose that contamination particle size (in...Ch. 4.4 - 4-46. Suppose that the probability density...Ch. 4.4 - 4-47. The thickness of a conductive coating in...Ch. 4.4 - 4-48. The probability density function of the...Ch. 4.4 - Prob. 49ECh. 4.5 - 4-50. Suppose that X has a continuous uniform...Ch. 4.5 - 4-51. Suppose X has a continuous uniform...Ch. 4.5 - 4-52. The net weight in pounds of a packaged...Ch. 4.5 - 4-53. The thickness of a flange on an aircraft...Ch. 4.5 - Prob. 54ECh. 4.5 - Prob. 55ECh. 4.5 - 4-56. An adult can lose or gain two pounds of...Ch. 4.5 - 4-57. A show is scheduled to start at 9:00 a.m.,...Ch. 4.5 - 4-58. The volume of a shampoo filled into a...Ch. 4.5 - 4-59. An e-mail message will arrive at a time...Ch. 4.5 - 4-60. Measurement error that is continuous and...Ch. 4.5 - 4-61. A beacon transmits a signal every 10 minutes...Ch. 4.5 - Prob. 62ECh. 4.6 - 4-63. Use Appendix Table III to determine the...Ch. 4.6 - 4-64. Use Appendix Table III to determine the...Ch. 4.6 - 4-65. Assume that Z has a standard normal...Ch. 4.6 - 4-66. Assume that Z has a standard normal...Ch. 4.6 - Prob. 67ECh. 4.6 - Prob. 68ECh. 4.6 - Prob. 69ECh. 4.6 - 4-70. Assume that X is normally distributed with a...Ch. 4.6 - 4-71. The compressive strength of samples of...Ch. 4.6 - 4-72. The time until recharge for a battery in a...Ch. 4.6 - 4-73. An article in Knee Surgery Sports Traumatol...Ch. 4.6 - 4-74. Cholesterol is a fatty substance that is an...Ch. 4.6 - Prob. 75ECh. 4.6 - 4-76. The fill volume of an automated filling...Ch. 4.6 - 4-77. In the previous exercise, suppose that the...Ch. 4.6 - 4-78. A driver’s reaction time to visual stimulus...Ch. 4.6 - 4-79. The speed of a file transfer from a server...Ch. 4.6 - 4-80. In 2002, the average height of a woman aged...Ch. 4.6 - 4-81. In an accelerator center, an experiment...Ch. 4.6 - 4-82. The demand for water use in Phoenix in 2003...Ch. 4.6 - Prob. 83ECh. 4.6 - 4-84. The diameter of the dot produced by a...Ch. 4.6 - Prob. 85ECh. 4.6 - Prob. 86ECh. 4.6 - Prob. 87ECh. 4.6 - 4-88. A study by Bechtel et al., 2009, described...Ch. 4.6 - 4-89. An article in Atmospheric Chemistry and...Ch. 4.6 - 4-90. The length of stay at a specific emergency...Ch. 4.6 - Prob. 91ECh. 4.6 - 4-92. An article in Microelectronics Reliability...Ch. 4.6 - Prob. 93ECh. 4.6 - 4-94. An article in the Journal of Cardiovascular...Ch. 4.7 - 4-95. Suppose that X is a binomial random variable...Ch. 4.7 - 4-96. Suppose that X is a Poisson random variable...Ch. 4.7 - 4-97. Suppose that X has a Poisson distribution...Ch. 4.7 - 4-98. The manufacturing of semiconductor chips...Ch. 4.7 - 4-99. There were 49.7 million people with some...Ch. 4.7 - 4-100. Phoenix water is provided to approximately...Ch. 4.7 - 4-101. An electronic office product contains 5000...Ch. 4.7 - 4-102. A corporate Web site contains errors on 50...Ch. 4.7 - 4-103. Suppose that the number of asbestos...Ch. 4.7 - 4-104. A high-volume printer produces minor...Ch. 4.7 - 4-105. Hits to a high-volume Web site are assumed...Ch. 4.7 - 4-106. An acticle in Biometrics [“Integrative...Ch. 4.7 - 4-107. An article in Atmospheric Chemistry and...Ch. 4.7 - 4-108. A set of 200 independent patients take...Ch. 4.7 - Prob. 109ECh. 4.7 - 4-110. Cabs pass your workplace according to a...Ch. 4.7 - 4-111. The number of (large) inclusions in cast...Ch. 4.8 - 4-112. Suppose that X has an exponential...Ch. 4.8 - Prob. 113ECh. 4.8 - 4-114. Suppose that X has an exponential...Ch. 4.8 - 4-115. Suppose that the counts recorded by a...Ch. 4.8 - 4-116. Suppose that the log-ons to a computer...Ch. 4.8 - 4-117. The time between calls to a plumbing supply...Ch. 4.8 - 4-118. The life of automobile voltage regulators...Ch. 4.8 - 4-119. Suppose that the time to failure (in hours)...Ch. 4.8 - 4-120. The time between the arrival of electronic...Ch. 4.8 - 4-121. The time between arrivals of taxis at a...Ch. 4.8 - Prob. 122ECh. 4.8 - 4-123. According to results from the analysis of...Ch. 4.8 - 4-124. The distance between major cracks in a...Ch. 4.8 - 4-125. The lifetime of a mechanical assembly in a...Ch. 4.8 - 4-126. The time between arrivals of small aircraft...Ch. 4.8 - Prob. 127ECh. 4.8 - Prob. 128ECh. 4.8 - Prob. 129ECh. 4.8 - Prob. 130ECh. 4.8 - Prob. 131ECh. 4.8 - Prob. 132ECh. 4.8 - Prob. 133ECh. 4.8 - 4-134. Requests for service in a queuing model...Ch. 4.8 - 4-135. An article in Vaccine [“Modeling the...Ch. 4.8 - 4-136. An article in Ad Hoc Networks [“Underwater...Ch. 4.9 - 4-137. Use the properties of the gamma function to...Ch. 4.9 - Prob. 138ECh. 4.9 - 4-139. Calls to a telephone system follow a...Ch. 4.9 - Prob. 140ECh. 4.9 - Prob. 141ECh. 4.9 - Prob. 142ECh. 4.9 - Prob. 143ECh. 4.9 - Prob. 144ECh. 4.9 - Prob. 145ECh. 4.9 - Prob. 146ECh. 4.9 - Prob. 147ECh. 4.9 - 4-148. Use the result for the gamma distribution...Ch. 4.9 - Prob. 149ECh. 4.9 - 4-150. The total service time of a multistep...Ch. 4.9 - Prob. 151ECh. 4.9 - 4-152. An article in Mathematical Biosciences...Ch. 4.10 - Prob. 153ECh. 4.10 - Prob. 154ECh. 4.10 - Prob. 155ECh. 4.10 - Prob. 156ECh. 4.10 - Prob. 157ECh. 4.10 - 4-158. Assume that the life of a packaged magnetic...Ch. 4.10 - Prob. 159ECh. 4.10 - Prob. 160ECh. 4.10 - Prob. 162ECh. 4.10 - Prob. 163ECh. 4.10 - Prob. 164ECh. 4.10 - Prob. 165ECh. 4.10 - Prob. 167ECh. 4.10 - Prob. 168ECh. 4.10 - Prob. 169ECh. 4.11 - 4-170. Suppose that X has a lognormal distribution...Ch. 4.11 - Prob. 171ECh. 4.11 - 4-172. Suppose that X has a lognormal distribution...Ch. 4.11 - 4-173. The length of time (in seconds) that a user...Ch. 4.11 - 4-174. Suppose that X has a lognormal distribution...Ch. 4.11 - 4-175. The lifetime of a semiconductor laser has a...Ch. 4.11 - Prob. 176ECh. 4.11 - Prob. 177ECh. 4.11 - Prob. 178ECh. 4.11 - Prob. 179ECh. 4.11 - Prob. 180ECh. 4.11 - Prob. 181ECh. 4.11 - Prob. 182ECh. 4.11 - Prob. 183ECh. 4.12 - Prob. 184ECh. 4.12 - Prob. 185ECh. 4.12 - Prob. 186ECh. 4.12 - Prob. 187ECh. 4.12 - Prob. 188ECh. 4.12 - Prob. 189ECh. 4.12 - Prob. 190ECh. 4.12 - Prob. 191ECh. 4 - Prob. 192SECh. 4 - Prob. 193SECh. 4 - Prob. 194SECh. 4 - 4-195. + The length of an injection-molded plastic...Ch. 4 - 4-196. + The sick-leave time of employees in a...Ch. 4 - Prob. 197SECh. 4 - Prob. 198SECh. 4 - 4-199. + When a bus service reduces fares, a...Ch. 4 - Prob. 200SECh. 4 - Prob. 201SECh. 4 - Prob. 202SECh. 4 - Prob. 203SECh. 4 - Prob. 204SECh. 4 - 4-205. + The CPU of a personal computer has a...Ch. 4 - Prob. 206SECh. 4 - Prob. 207SECh. 4 - Prob. 208SECh. 4 - 4-209. + Without an automated irrigation system,...Ch. 4 - 4-210. With an automated irrigation system, a...Ch. 4 - Prob. 211SECh. 4 - Prob. 212SECh. 4 - Prob. 213SECh. 4 - Prob. 214SECh. 4 - Prob. 215SECh. 4 - Prob. 216SECh. 4 - 4-217. + A square inch of carpeting contains 50...Ch. 4 - Prob. 218SECh. 4 - Prob. 219SECh. 4 - 4-221. Consider the regional right ventricle...Ch. 4 - Prob. 222SECh. 4 - Prob. 223SECh. 4 - Prob. 224SECh. 4 - Prob. 225SECh. 4 - Prob. 226SECh. 4 - Prob. 227SECh. 4 - Prob. 228SECh. 4 - Prob. 229SECh. 4 - Prob. 230SECh. 4 - Prob. 231SECh. 4 - Prob. 232SECh. 4 - Prob. 233SECh. 4 - 4-234. A process is said to be of six-sigma...
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