Statistics for Business and Economics (13th Edition)
13th Edition
ISBN: 9780134648385
Author: MCCLAVE
Publisher: PEARSON
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Chapter 8.4, Problem 8.54ACI
Traffic sign maintenance. The Federal Highway Administration (FHWA) recently issued new guidelines for maintaining and replacing traffic signs. Civil engineers at North Carolina State University conducted a study of the effectiveness of various sign maintenance practices developed to adhere to the new guidelines and published the results in the Journal of Transportation Engineering (June 2013). One portion of the study focused on the proportion of traffic signs that fail the minimum FHWA retroreflectivity requirements. Of 1,000 signs maintained by the North Carolina Department of Transportation (NCDOT), 512 were deemed failures. Of 1,000 signs maintained by county-owned roads in North Carolina, 328 were deemed failures. Conduct a test of hypothesis to determine whether the true proportions of traffic signs that fail the minimum FHWA retroreflectivity requirements differ depending on whether the signs are maintained by the NCDOT or by the county. Test using α = .05.
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Chapter 8 Solutions
Statistics for Business and Economics (13th Edition)
Ch. 8.2 - The purpose of this exercise is to compare the...Ch. 8.2 - Prob. 8.2LMCh. 8.2 - In order to compare the means of two populations,...Ch. 8.2 - Prob. 8.4LMCh. 8.2 - Prob. 8.5LMCh. 8.2 - Prob. 8.6LMCh. 8.2 - Independent random samples from normal populations...Ch. 8.2 - Two independent random samples nave been...Ch. 8.2 - Independent random samples of n1 = 233 and n2 =...Ch. 8.2 - Independent random samples from approximately...
Ch. 8.2 - Independent random samples selected from two...Ch. 8.2 - Lobster trap placement. Refer to the Bulletin of...Ch. 8.2 - Last name and acquisition timing. The speed with...Ch. 8.2 - Shared leadership in airplane crews. Human Factors...Ch. 8.2 - Performance-based logistics. Refer to the Journal...Ch. 8.2 - Drug content assessment. Refer to Exercise 4.123...Ch. 8.2 - Buy-side vs. sell-side analysts earnings...Ch. 8.2 - Homework assistance for accounting students. How...Ch. 8.2 - Comparing taste-test rating protocols....Ch. 8.2 - Producer willingness to supply biomass. The...Ch. 8.2 - Does rudeness really matter in the workplace?...Ch. 8.2 - Prob. 8.22ACICh. 8.2 - Is honey a cough remedy? Refer to the Archives of...Ch. 8.2 - Gender diversity of board of directors. The gender...Ch. 8.2 - Prob. 8.25ACACh. 8.3 - A paired difference experiment produced the...Ch. 8.3 - A paired difference experiment yielded nd pairs of...Ch. 8.3 - The data for a random sample of six paired...Ch. 8.3 - The data for a random sample of 10 paired...Ch. 8.3 - A paired difference experiment yielded the...Ch. 8.3 - Summer weight-loss camp. Camp Jump Start is an...Ch. 8.3 - Performance ratings of government agencies. The...Ch. 8.3 - Twinned drill holes. A traditional method of...Ch. 8.3 - Prob. 8.34ACBCh. 8.3 - I am not selling anything surveys. To improve...Ch. 8.3 - Consumers attitudes toward advertising. The two...Ch. 8.3 - Taking power naps during work breaks. Lack of...Ch. 8.3 - Acidity of mouthwash. Acid has been found to be a...Ch. 8.3 - Solar energy generation along highways. The...Ch. 8.3 - Impact of red light cameras on car crashes. To...Ch. 8.3 - Prob. 8.41ACICh. 8.3 - Alcoholic fermentation in wines. Determining...Ch. 8.4 - Consider making an inference about p1 p2, where...Ch. 8.4 - For each of the following values of , find the...Ch. 8.4 - Prob. 8.45LMCh. 8.4 - Prob. 8.46LMCh. 8.4 - Prob. 8.47LMCh. 8.4 - Prob. 8.48LMCh. 8.4 - The winners curse in auction bidding. In auction...Ch. 8.4 - Prob. 8.50ACBCh. 8.4 - Prob. 8.51ACBCh. 8.4 - Web survey response rates. Response rates to Web...Ch. 8.4 - Hospital administration of malaria patients. One...Ch. 8.4 - Traffic sign maintenance. The Federal Highway...Ch. 8.4 - Salmonella in produce. Salmonella infection is the...Ch. 8.4 - Angioplastys benefits challenged. More than 1...Ch. 8.4 - Entrepreneurial careers of MBA alumni. Are African...Ch. 8.4 - Predicting software defects. Refer to the PROMISE...Ch. 8.4 - Prob. 8.59ACICh. 8.4 - Religious symbolism in TV commercials. Gonzaga...Ch. 8.5 - Assuming that n1 = n2, find the sample sizes...Ch. 8.5 - Find the appropriate values of n1 and n2 (assume...Ch. 8.5 - Suppose you want to estimate the difference...Ch. 8.5 - Enough money has been budgeted to collect...Ch. 8.5 - Last name and acquisition timing. Refer to the...Ch. 8.5 - Homework assistance for accounting students. Refer...Ch. 8.5 - Vulnerability of relying party Web sites. Refer to...Ch. 8.5 - Conducting a political poll. A pollster wants to...Ch. 8.5 - Shared leadership in airplane crews. Refer to the...Ch. 8.5 - Solar energy generation along highways. Refer to...Ch. 8.5 - Angioplastys benefits challenged. Refer to the...Ch. 8.5 - Traffic sign maintenance. Refer to the Journal of...Ch. 8.6 - Use Tables V, VI, VII, and VIII in Appendix D to...Ch. 8.6 - Given v1 and v2, find the following probabilities:...Ch. 8.6 - For each of the following cases, identify the...Ch. 8.6 - For each of the following cases, identify the...Ch. 8.6 - Specify the appropriate rejection region for...Ch. 8.6 - Independent random samples were selected from each...Ch. 8.6 - Independent random samples were selected from each...Ch. 8.6 - Lobster trap placement. Refer to the Bulletin of...Ch. 8.6 - Prob. 8.81ACBCh. 8.6 - Mental health of workers and the unemployed. A...Ch. 8.6 - Drug content assessment Refer to Exercise 8.16 (p....Ch. 8.6 - Last name and acquisition timing. Refer to the...Ch. 8.6 - Prob. 8.85ACICh. 8.6 - Oil content of fried sweet potato chips. Refer to...Ch. 8.6 - Shopping vehicle and judgment. Refer to the...Ch. 8.6 - Is honey a cough remedy? Refer to the Archives of...Ch. 8 - List the assumptions necessary for each of the...Ch. 8 - Two independent random samples were selected from...Ch. 8 - Independent random samples were selected from two...Ch. 8 - Independent random samples were selected from two...Ch. 8 - Two independent random samples are taken from two...Ch. 8 - A random sample of five pairs of observations were...Ch. 8 - Prob. 8.95ACBCh. 8 - Prob. 8.96ACBCh. 8 - Prob. 8.97ACBCh. 8 - Hull failures of oil tankers. Refer to the Marine...Ch. 8 - Effectiveness of teaching software. The U.S....Ch. 8 - Durability of shock absorbers. A manufacturer of...Ch. 8 - NHTSA new car crash tests. Refer to the National...Ch. 8 - Diamonds sold at retail. Refer to the data for 308...Ch. 8 - Childrens recall of TV ads. A study examined...Ch. 8 - Is steak your favorite barbeque food? July is...Ch. 8 - Planning habits survey. American Demographics...Ch. 8 - Turnover rates in the United States and Japan....Ch. 8 - Smartphone usage differs by gender. The role of...Ch. 8 - Life expectancies of working women and housewives....Ch. 8 - Comparing purchasers and nonpurchasers of...Ch. 8 - Prob. 8.110ACICh. 8 - Racial profiling by the LAPD. Racial profiling is...Ch. 8 - State SAT scores. Refer to Exercise 2.27 (p. 60)...Ch. 8 - Rat damage to sugarcane fields. Poisons are used...Ch. 8 - Environmental impact study. Some power plants are...Ch. 8 - Instrument precision. When new instruments are...Ch. 8 - Cooling method for gas turbines. Refer to the...Ch. 8 - Average housing space per person. Even though...Ch. 8 - Positive spillover effects from self-managed work...Ch. 8 - Impact of gender on advertising. How does gender...Ch. 8 - Salaries of postgraduates. Refer to the Economics...Ch. 8 - Gambling in public high schools. With the rapid...Ch. 8 - CareerBank.com annual salary survey....Ch. 8 - Facility layout study. Facility layout and...
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