Concept explainers
On December 25, 2009, an airline passenger was subdued while attempting to blow up a Northwest Airlines flight headed for Detroit, Michigan. The passenger had smuggled explosives hidden in his underwear past a metal detector at an airport screening facility. As a result, the Transportation Security Administration (TSA) proposed installing full-body scanners to replace the metal detectors at the nation’s largest airports. This proposal resulted in strong objections from privacy advocates who considered the scanners an invasion of privacy. On January 5-6, 2010, USA Today conducted a poll of 542 adults to learn what proportion of airline travelers approved of using full-body scanners (USA Today, January 11, 2010). The poll results showed that 455 of the respondents felt that full-body scanners would improve airline security and 423 indicated that they approved of using the devices.
- a. conduct a hypothesis test to determine if the results of the poll justify concluding that over 80% of airline travelers feel that the use of full-body scanners will improve airline security. Use α = .05.
- b. Suppose the TSA will go forward with the installation and mandatory use of full-body scanners if over 75% of airline travelers approve of using the devices. You have been told to conduct a statistical analysis using the poll results to determine if the TSA should require mandatory use of the full-body scanners. Because this is viewed as a very sensitive decision, use α = .01. What is your recommendation?
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Chapter 9 Solutions
Statistics for Business & Economics
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- the hand wrriting is badarrow_forwardSomeone is identical to the Zodiac Killerarrow_forwardIn the Aloha state, you are very unlikely to be murdered! However, it is considerably more likely that your house might be burgled, your car might be stolen, or you might be punched in the nose. That said, Hawaii is still a great place for a vacation or, if you are very lucky, to live. The following numbers represent the crime rates per 100,000 population in Hawaii: murder, 1.6; rape, 21.4; robbery, 95.3; house burglary, 903.6; motor vehicle theft, 521.7; assault, 106.3. (a) Display this information in a Pareto chart, showing the crime rate for each category. (b) Could the information as reported be displayed as a circle graph? Explain. Hint: Other forms of crime, such as arson, are not included in the information. In addition, some crimes might occur together. A. Yes, but the graph would take into account only multiple crimes and not these particular individual crimes. B. Yes, the graph would be able to account for all information. C. No, the graph would be unable to account…arrow_forward
- is race catagorical or quanitativearrow_forwardIn the Aloha State, you are very unlikely to be murdered! However, it is considerably more likely that your house might be burgled, your car might be stolen, or you might be punched in the nose. That said, Hawaii is still a great place for a vacation or, if you are very lucky, to live. The following numbers represent the crime rates per 100,000 population in Hawaii: murder, 4.6; rape, 32.4; robbery, 91.3; house burglary, 876.6; motor vehicle theft, 549.7; assault, 132.3. (a) Display this information in a Pareto chart, showing the crime rate for each category. (b) Could the information as reported be displayed as a circle graph? (Explain. Hint: Other forms of crime, such as arson, are not included in the information. In addition, some crimes might occur together.) a) Yes, but the graph would take into account only multiple crimes and not these particular individual crimes. b) No, the graph would be unable to account for all information. c) Yes, but the graph would take into…arrow_forwardIn the Aloha state, you are very unlikely to be murdered! However, it is considerably more likely that your house might be burgled, your car might be stolen, or you might be punched in the nose. That said, Hawaii is still a great place for a vacation or, if you are very lucky, to live. The following numbers represent the crime rates per 100,000 population in Hawaii: murder, 3.6; rape, 29.4; robbery, 79.3; house burglary, 867.6; motor vehicle theft, 531.7; assault, 118.3. Could the information as reported be displayed as a circle graph? Explain. Hint: Other forms of crime, such as arson, are not included in the information. In addition, some crimes might occur together.arrow_forward
- Adams County, Nebraska 33,024 31,126 31,181 31,299 31,367 31,396 Antelope County, Nebraska 6,729 6,742 6,697 6,655 6,600 6,531 Arthur County, Nebraska 364 426 448 490 507 476 Banner County, Nebraska 824 720 703 778 816 788 Blaine County, Nebraska 471 539 585 584 586 594 Boone County, Nebraska 5,531 5,553 5,512 5,473 5,441 5,404 Box Butte County, Nebraska 11,031 11,372 11,383 11,345 11,312 11,308 Boyd County, Nebraska 2,120 2,107 2,095 2,025 2,093 2,067 Brown County, Nebraska 3,178 3,192 3,153 3,183 3,167 3,090 Buffalo County, Nebraska 44,877 45,437 45,842 46,330 46,885 47,388 Burt County, Nebraska 7,047 6,964 6,901 6,829 6,748 6,690 Butler County, Nebraska 8,416 8,382 8,360 8,345 8,334 8,312 Cass County, Nebraska 25,495 25,246 25,230 25,214 25,222 25,315 Cedar County, Nebraska 8,582 8,906 8,839 8,807 8,790 8,736 Chase County, Nebraska 3,702 3,927 3,937 3,964 3,984 3,990 Cherry County, Nebraska 5,682 5,783 5,750 5,722 5,735 5,749 Cheyenne County, Nebraska…arrow_forwardAT&T was running commercials in 1990 aimed at luring back customers whohad switched to one of the other long-distance phone service providers. One suchcommercial shows a businessman trying to reach Phoenix and mistakenly gettingFiji, where a half-naked native on a beach responds incomprehensibly in Polynesian.When asked about this advertisement, AT&T admitted that the portrayed incidentdid not actually take place but added that this was an enactment of something that“could happen.”12 Suppose that one in 200 long-distance telephone calls is misdirected. What is the probability that at least one in five attempted telephone calls reachesthe wrong number? (Assume independence of attempts.)Refer to the information in the previous problem. Given that your longdistance telephone call is misdirected, there is a 2% chance that you will reach a foreign country (such as Fiji). Suppose that I am now going to dial a single long-distancenumber. What is the probability that I will erroneously…arrow_forwardBecause of the complex nature of the U.S. income tax system, many people have questions for the Internal Revenue Service (IRS). Yet an article published by the Detroit Free Press titled “Assistance: IRS Help Centers Give the Wrong Information” discusses the propensity of IRS staff employees to give incorrect tax information to taxpayers who call with questions. Then IRS Inspector General Pamela Gardiner told a Senate subcommittee that “the IRS employees at 400 taxpayer assistance centers nationwide encountered 8.5 million taxpayers face-to-face last year. The problem: When inspector general auditors posing as taxpayers asked them to answer tax questions, the answers were right 69% of the time.” Suppose an independent commission was formed to test whether the 0.69 accuracy rate is correct or whether it is actually higher or lower. The commission has randomly selected n = 180 tax returns that were completed by IRS assistance employees and found that 105 of the returns were…arrow_forward
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