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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Chapter 6.7, Problem 6.97ACB
Oil content of fried sweet potato chips. The characteristics of sweet potato chips fried at different temperatures were investigated in the Journal of Food Engineering (September 2013). A sample of 6 sweet potato slices were fried at 130° using a vacuum fryer. One characteristic of interest to the researchers was internal oil content (measured in millions of grams). The results were:
- a. Identify the target parameter, in symbols and words.
- b. Compute a 95% confidence interval for σ2.
- c. What does it mean to say that the target parameter lies within the interval with “95% confidence”?
- d. What assumption about the data must be satisfied in order for the confidence interval to be valid?
- e. To obtain a practical interpretation of the interval, part b, explain why a confidence interval for the standard deviation, σ, is desired.
- f. Use the results, part b, to compute a 95% confidence interval for σ. Give a practical interpretation of the interval.
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Please show me your solutions and interpretations. Show the completehypothesis-testing procedure.A manufacturing company produces bearings. One line of bearings is specified to be 1.64 centimeters (cm) in diameter. A major customer requires that the variance of the bearings be no more than 0.001 cm2. The producer is required to test the bearings before they are shipped, and so the diameters of 16 bearings are measured with a precise instrument, resulting in the following values:1.69 1.62 1.63 1.70 1.66 1.63 1.65 1.71 1.64 1.69 1.57 1.64 1.59 1.66 1.63 1.65Assume bearing diameters are normally distributed. Use the data and α = 0.025 to test the data to determine whether the population of these bearings is to be rejected because of too high variance.
Unfortunately, arsenic occurs naturally in some ground water. A mean arsenic level of u = 8 parts
per billion (ppb) is considered safe for agricultural use. A well in Los Banos is used to water cotton
crops. This well is tested on a regular basis for arsenic. A random sample of 37 tests gave a sample
mean of
= 7.3ppb arsenic. It is known that o = 1.9 ppb for this type of data. Does this
information indicate that the mean level of arsenic in this well is less than 8 ppb? Use the classical
approach. Use a = 0.01
What is the Decision (step 5) for this problem?
There is not sufficient evidence at the 0.01 level of significance to show the mean arsenic level in the Los
Banos well is less than 7.3 ppb.
O There is sufficient evidence at the 0.01 level of significance to show the mean arsenic level in the Los Banos
well is less than 8.0 ppb.
There is not sufficient evidence at the 0.01 level of significance to show the mean arsenic level in the Los
Banos well is less than 8.0 ppb.
O There is…
Unfortunately, arsenic occurs naturally in some ground water. A mean arsenic level of µ = 8 parts
per billion (ppb) is considered safe for agricultural use. A well in Los Banos is used to water cotton
crops. This well is tested on a regular basis for arsenic. A random sample of 37 tests gave a sample
mean of
= 7.3ppb arsenic. It is known that o =
1.9ppb for this type of data. Does this
information indicate that the mean level of arsenic in this well is less than 8 ppb? Use the classical
approach. Use a = 0.01
What is the calculation (step 4) for this problem?
Z = -2.34
z = 2.34
z = 2.24
z = -2.24
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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