Statistics for Business and Economics (13th Edition)
13th Edition
ISBN: 9780134506593
Author: James T. McClave, P. George Benson, Terry Sincich
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 6.118ACB
Bankruptcy effect on U.S. airfares. Both Delta Airlines and USAir filed for bankruptcy. A study of the impact of bankruptcy on the fares charged by U.S. airlines was published in Research in Applied Economics (Vol. 2: 2010). The researchers collected data on Orlando-bound airfares for three airlines—Southwest (a stable airline). Delta (just entering bankruptcy at the time), and USAir (emerging from bankruptcy). A large sample of nonrefundable ticket prices was obtained for each airline following USAir’s emergence from bankruptcy, and then a 95% confidence interval for the true
Airline | 95% Confidence Interval |
Southwest | (S412, $496) |
Delta | (S468, $500) |
USAir | (S247, $372) |
- a. What confidence coefficient was used to generate the confidence intervals?
- b. Give a practical interpretation of each of the 95% confidence intervals. Use the phrase "95% confident' in your answer.
- c. When you say you are “95% confident.” what do you mean?
- d. If you want to reduce the width of each confidence interval, should you use a smaller or larger confidence coefficient? Explain.
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Chapter 6 Solutions
Statistics for Business and Economics (13th Edition)
Ch. 6.2 - Find z/2 for each of the following: a. a . = .10...Ch. 6.2 - What is the confidence level of each of the...Ch. 6.2 - A random sample of n measurements was selected...Ch. 6.2 - A random sample of 90 observations produced a mean...Ch. 6.2 - A random sample of 70 observations from a normally...Ch. 6.2 - Use the applet Confidence Intervals for a Mean...Ch. 6.2 - Use the applet Confidence Intervals for a Mean...Ch. 6.2 - Prob. 6.6LMCh. 6.2 - Explain the difference between an interval...Ch. 6.2 - Prob. 6.8LM
Ch. 6.2 - Will a large-sample confidence interval be valid...Ch. 6.2 - Heart rate variability of police officers. Are...Ch. 6.2 - Tipping points in daily deal transactions? Online...Ch. 6.2 - Corporate sustainability of CPA firms. Corporate...Ch. 6.2 - College dropout study. Refer to the American...Ch. 6.2 - Wear-out of used display panels. Refer to Exercise...Ch. 6.2 - Unethical corporate conduct. How complicit are...Ch. 6.2 - Shopping on Black Friday. The day after...Ch. 6.2 - 401 (k) Participation rates. Named for the section...Ch. 6.2 - Accounting and Machiavellianism. Refer to the...Ch. 6.2 - Facial structure of CEOs. In Psychological Science...Ch. 6.2 - Improving SAT scores. Refer to the Chance (Winter...Ch. 6.2 - The Raid test kitchen. According to scientists,...Ch. 6.3 - Suppose you have selected a random sample of n = 5...Ch. 6.3 - Use the applet Confidence Intervals for a Mean...Ch. 6.3 - Use the applet Confidence Intervals for a Mean...Ch. 6.3 - Explain the differences in the sampling...Ch. 6.3 - Let t0 be a specific value of t. Use Table III in...Ch. 6.3 - The following random sample was selected from a...Ch. 6.3 - The following sample of 16 measurements was...Ch. 6.3 - Lobster trap placement. An observational study of...Ch. 6.3 - Radon exposure in Egyptian tombs. Many ancient...Ch. 6.3 - Do social robots walk or roll? Refer to the...Ch. 6.3 - Hospital length of stay. Health insurers and the...Ch. 6.3 - Repair and replacement costs of water pipes. Refer...Ch. 6.3 - Prob. 6.34ACICh. 6.3 - Oxygen bubbles in molten salt. Molten salt is used...Ch. 6.3 - Performance of stock screeners. In Exercise 2.44...Ch. 6.3 - Minimizing tractor skidding distance. When...Ch. 6.3 - Crude oil biodegradation. Refer to the Journal of...Ch. 6.3 - Largest private companies. IPOsinitial public...Ch. 6.4 - Describe the sampling distribution of p based on...Ch. 6.4 - Use the applet Confidence Intervals for a...Ch. 6.4 - Prob. 6.6AECh. 6.4 - For the binomial sample information summarized in...Ch. 6.4 - A random sample of size n = 121 yielded p=.88. a....Ch. 6.4 - A random sample of size n = 225 yielded p=.46. a....Ch. 6.4 - A random sample of 50 consumers taste-tested a new...Ch. 6.4 - Customer participation in store loyalty card...Ch. 6.4 - Crash risk of using cell phones while driving....Ch. 6.4 - Zillow.com estimates of home values. Zillow.com is...Ch. 6.4 - Do social robots walk or roll? Refer to the...Ch. 6.4 - Is Starbucks coffee overpriced? The Minneapolis...Ch. 6.4 - Nannies who are INA certified. The International...Ch. 6.4 - Prob. 6.51ACICh. 6.4 - Prob. 6.52ACICh. 6.4 - Minority ownership of franchises. According to a...Ch. 6.4 - Study of aircraft bird-strikes. As worldwide air...Ch. 6.4 - Prob. 6.55ACICh. 6.4 - Diamonds sold on the open market. Refer to the...Ch. 6.4 - Are you really being served red snapper? Refer to...Ch. 6.4 - Eye shadow, mascara, and nickel allergies....Ch. 6.4 - Prob. 6.59ACACh. 6.5 - If you wish to estimate a population mean with a...Ch. 6.5 - Suppose you wish to estimate a population mean...Ch. 6.5 - In each case, find the approximate sample size...Ch. 6.5 - The following is a 90% confidence interval for p:...Ch. 6.5 - It costs you 10 to draw a sample of size n = 1 and...Ch. 6.5 - Suppose you wish to estimate the mean of a normal...Ch. 6.5 - If nothing is known about p. .5 can be substituted...Ch. 6.5 - Aluminum cans contaminated by fire. A gigantic...Ch. 6.5 - Accounting and Machiavellianism. Refer to the...Ch. 6.5 - Lobster trap placement. Refer to the Bulletin of...Ch. 6.5 - Evaporation from swimming pools. Refer to the...Ch. 6.5 - Do social robots walk or roll? Refer to the...Ch. 6.5 - Study of aircraft bird-strikes. Refer to the...Ch. 6.5 - Bacteria in bottled water. Is the bottled water...Ch. 6.5 - Shopping on Black Friday. Refer to the...Ch. 6.5 - Monitoring phone calls to a toll-free number. A...Ch. 6.5 - Eye shadow, mascara, and nickel allergies. Refer...Ch. 6.5 - Prob. 6.77ACICh. 6.5 - Is caffeine addictive? Does the caffeine in...Ch. 6.5 - Prob. 6.79ACACh. 6.6 - Calculate the percentage of the population sampled...Ch. 6.6 - Suppose the standard deviation of the population...Ch. 6.6 - Suppose N = 5,000, n = 64, and s = 24. a. Compare...Ch. 6.6 - Suppose N = 10,000, n = 2,000. and s = 50. a....Ch. 6.6 - Prob. 6.84LMCh. 6.6 - Prob. 6.85LMCh. 6.6 - Prob. 6.86LMCh. 6.6 - NFL player survey. Researchers at the University...Ch. 6.6 - Magazine subscriber salaries. Each year, the trade...Ch. 6.6 - Auditing sampling methods. Traditionally. auditors...Ch. 6.6 - Prob. 6.90ACICh. 6.6 - Invoice errors in a billing system In a study of...Ch. 6.6 - Prob. 6.92ACACh. 6.7 - For each of the following combinations of and...Ch. 6.7 - Given the following values of x, s, and n, form a...Ch. 6.7 - Prob. 6.95LMCh. 6.7 - A random sample of n = 6 observations from a...Ch. 6.7 - Oil content of fried sweet potato chips. The...Ch. 6.7 - Corporate sustainability of CPA firms. Refer to...Ch. 6.7 - Facial structure of CEOs. Refer to the...Ch. 6.7 - Radon exposure in Egyptian tombs. Refer to the...Ch. 6.7 - Drug content assessment. Refer to the Analytical...Ch. 6.7 - Jitter in a water power system. Jitter is a term...Ch. 6.7 - Lobster trap placement Refer to the Bulletin of...Ch. 6.7 - Phishing attacks on e-mail accounts. Refer to the...Ch. 6.7 - Is honey a cough remedy? Refer to the Archives of...Ch. 6 - In each of the following instances determine...Ch. 6 - In random Sample of 400 measurements, 227 of the...Ch. 6 - Prob. 6.109LMCh. 6 - Calculate the finite population correction factor...Ch. 6 - Find /22 and (1/2)2 from Table IV, Appendix D, for...Ch. 6 - Latex allergy in health care workers. Health care...Ch. 6 - Prob. 6.113ACBCh. 6 - Products Made in the USA. Refer to Exercise 2.154...Ch. 6 - Prob. 6.115ACBCh. 6 - Lead and copper in drinking water. Periodically,...Ch. 6 - Water pollution testing. The EPA wants to test a...Ch. 6 - Bankruptcy effect on U.S. airfares. Both Delta...Ch. 6 - Prob. 6.119ACBCh. 6 - Motivation of drug dealers. Refer to the Applied...Ch. 6 - Budget lapsing at army hospitals Budget lapsing...Ch. 6 - Size of diamonds sold at retail. Refer to Exercise...Ch. 6 - Prob. 6.123ACICh. 6 - Prob. 6.124ACICh. 6 - Surface roughness of pipe. Refer to the...Ch. 6 - Interviewing candidates for a job. The costs...Ch. 6 - Overbooking policies for major airlines. Airlines...Ch. 6 - Paying for music downloads if you use the...Ch. 6 - Accuracy of price scanners at Walmart. The...Ch. 6 - Contamination of New Jersey wells. Methyl t-butyl...Ch. 6 - Cell phone use by drivers. Studies have shown that...Ch. 6 - Salmonella poisoning from eating an ice cream bar....Ch. 6 - Prob. 6.133ACICh. 6 - Latex allergy in health care workers. Refer to the...Ch. 6 - Prob. 6.135ACACh. 6 - Accountants salary survey. Each year, Management...Ch. 6 - Prob. 6.137ACACh. 6 - A sampling dispute goes to court. Sampling of...Ch. 6 - Prob. 6.139CTC
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