STATISTICS F/BUS.+ECON.-ACCESS(24WKS.)
13th Edition
ISBN: 9780134596839
Author: MCCLAVE
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 6, Problem 6.120ACB
Motivation of drug dealers. Refer to the Applied Psychology in Criminal Justice (September 2009) study of the personality characteristics of convicted drug dealers, Exercise 5.75 (p. 301). A random sample of 100 drug dealers had a mean Wanting Recognition (WR) score of 39 points, with a standard deviation of 6 points. The researchers are interested in σ2, the variation in WR scores for all convicted drug dealers.
- a. Identify the target parameter, in symbols and words.
- b. Compute a 99% confidence interval for σ2.
- c. What does it mean to say that the target parameter lies within the interval with “99% 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 99% confidence interval for σ. Give a practical interpretation of the interval.
Expert Solution & Answer

Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Une Entreprise œuvrant dans le domaine du multividéo donne l'opportunité à ses
programmeurs-analystes d'évaluer la performance des cadres supérieurs.
Voici les résultats obtenues (sur une échelle de 10 à 50) où 50 représentent une
excellente performance. 10 programmeurs furent sélectionnés au hazard pour
évaluer deux cadres. Un rapport Excel est également fourni.
Programmeurs
Cadre A Cadre B
1
34
36
2
32
34
3
18
19
33
38
19
21
21
23
7
35
34
8
20
20
9
34
34
10
36
34
Test d'égalité des espérances: observations pairées
A television news channel samples 25 gas stations from its local area and uses the results to estimate the average gas price for the state. What’s wrong with its margin of error?
You’re fed up with keeping Fido locked inside, so you conduct a mail survey to find out people’s opinions on the new dog barking ordinance in a certain city. Of the 10,000 people who receive surveys, 1,000 respond, and only 80 are in favor of it. You calculate the margin of error to be 1.2 percent. Explain why this reported margin of error is misleading.
Chapter 6 Solutions
STATISTICS F/BUS.+ECON.-ACCESS(24WKS.)
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
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- You find out that the dietary scale you use each day is off by a factor of 2 ounces (over — at least that’s what you say!). The margin of error for your scale was plus or minus 0.5 ounces before you found this out. What’s the margin of error now?arrow_forwardSuppose that Sue and Bill each make a confidence interval out of the same data set, but Sue wants a confidence level of 80 percent compared to Bill’s 90 percent. How do their margins of error compare?arrow_forwardSuppose that you conduct a study twice, and the second time you use four times as many people as you did the first time. How does the change affect your margin of error? (Assume the other components remain constant.)arrow_forward
- Out of a sample of 200 babysitters, 70 percent are girls, and 30 percent are guys. What’s the margin of error for the percentage of female babysitters? Assume 95 percent confidence.What’s the margin of error for the percentage of male babysitters? Assume 95 percent confidence.arrow_forwardYou sample 100 fish in Pond A at the fish hatchery and find that they average 5.5 inches with a standard deviation of 1 inch. Your sample of 100 fish from Pond B has the same mean, but the standard deviation is 2 inches. How do the margins of error compare? (Assume the confidence levels are the same.)arrow_forwardA survey of 1,000 dental patients produces 450 people who floss their teeth adequately. What’s the margin of error for this result? Assume 90 percent confidence.arrow_forward
- The annual aggregate claim amount of an insurer follows a compound Poisson distribution with parameter 1,000. Individual claim amounts follow a Gamma distribution with shape parameter a = 750 and rate parameter λ = 0.25. 1. Generate 20,000 simulated aggregate claim values for the insurer, using a random number generator seed of 955.Display the first five simulated claim values in your answer script using the R function head(). 2. Plot the empirical density function of the simulated aggregate claim values from Question 1, setting the x-axis range from 2,600,000 to 3,300,000 and the y-axis range from 0 to 0.0000045. 3. Suggest a suitable distribution, including its parameters, that approximates the simulated aggregate claim values from Question 1. 4. Generate 20,000 values from your suggested distribution in Question 3 using a random number generator seed of 955. Use the R function head() to display the first five generated values in your answer script. 5. Plot the empirical density…arrow_forwardFind binomial probability if: x = 8, n = 10, p = 0.7 x= 3, n=5, p = 0.3 x = 4, n=7, p = 0.6 Quality Control: A factory produces light bulbs with a 2% defect rate. If a random sample of 20 bulbs is tested, what is the probability that exactly 2 bulbs are defective? (hint: p=2% or 0.02; x =2, n=20; use the same logic for the following problems) Marketing Campaign: A marketing company sends out 1,000 promotional emails. The probability of any email being opened is 0.15. What is the probability that exactly 150 emails will be opened? (hint: total emails or n=1000, x =150) Customer Satisfaction: A survey shows that 70% of customers are satisfied with a new product. Out of 10 randomly selected customers, what is the probability that at least 8 are satisfied? (hint: One of the keyword in this question is “at least 8”, it is not “exactly 8”, the correct formula for this should be = 1- (binom.dist(7, 10, 0.7, TRUE)). The part in the princess will give you the probability of seven and less than…arrow_forwardplease answer these questionsarrow_forward
- Selon une économiste d’une société financière, les dépenses moyennes pour « meubles et appareils de maison » ont été moins importantes pour les ménages de la région de Montréal, que celles de la région de Québec. Un échantillon aléatoire de 14 ménages pour la région de Montréal et de 16 ménages pour la région Québec est tiré et donne les données suivantes, en ce qui a trait aux dépenses pour ce secteur d’activité économique. On suppose que les données de chaque population sont distribuées selon une loi normale. Nous sommes intéressé à connaitre si les variances des populations sont égales.a) Faites le test d’hypothèse sur deux variances approprié au seuil de signification de 1 %. Inclure les informations suivantes : i. Hypothèse / Identification des populationsii. Valeur(s) critique(s) de Fiii. Règle de décisioniv. Valeur du rapport Fv. Décision et conclusion b) A partir des résultats obtenus en a), est-ce que l’hypothèse d’égalité des variances pour cette…arrow_forwardAccording to an economist from a financial company, the average expenditures on "furniture and household appliances" have been lower for households in the Montreal area than those in the Quebec region. A random sample of 14 households from the Montreal region and 16 households from the Quebec region was taken, providing the following data regarding expenditures in this economic sector. It is assumed that the data from each population are distributed normally. We are interested in knowing if the variances of the populations are equal. a) Perform the appropriate hypothesis test on two variances at a significance level of 1%. Include the following information: i. Hypothesis / Identification of populations ii. Critical F-value(s) iii. Decision rule iv. F-ratio value v. Decision and conclusion b) Based on the results obtained in a), is the hypothesis of equal variances for this socio-economic characteristic measured in these two populations upheld? c) Based on the results obtained in a),…arrow_forwardA major company in the Montreal area, offering a range of engineering services from project preparation to construction execution, and industrial project management, wants to ensure that the individuals who are responsible for project cost estimation and bid preparation demonstrate a certain uniformity in their estimates. The head of civil engineering and municipal services decided to structure an experimental plan to detect if there could be significant differences in project evaluation. Seven projects were selected, each of which had to be evaluated by each of the two estimators, with the order of the projects submitted being random. The obtained estimates are presented in the table below. a) Complete the table above by calculating: i. The differences (A-B) ii. The sum of the differences iii. The mean of the differences iv. The standard deviation of the differences b) What is the value of the t-statistic? c) What is the critical t-value for this test at a significance level of 1%?…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill

Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Statistics 4.1 Point Estimators; Author: Dr. Jack L. Jackson II;https://www.youtube.com/watch?v=2MrI0J8XCEE;License: Standard YouTube License, CC-BY
Statistics 101: Point Estimators; Author: Brandon Foltz;https://www.youtube.com/watch?v=4v41z3HwLaM;License: Standard YouTube License, CC-BY
Central limit theorem; Author: 365 Data Science;https://www.youtube.com/watch?v=b5xQmk9veZ4;License: Standard YouTube License, CC-BY
Point Estimate Definition & Example; Author: Prof. Essa;https://www.youtube.com/watch?v=OTVwtvQmSn0;License: Standard Youtube License
Point Estimation; Author: Vamsidhar Ambatipudi;https://www.youtube.com/watch?v=flqhlM2bZWc;License: Standard Youtube License