An Introduction to Statistical Methods and Data Analysis
7th Edition
ISBN: 9781305269477
Author: R. Lyman Ott, Micheal T. Longnecker
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 4.18, Problem 34E
In a January 15, 1998, article, the New England Journal of Medicine (338:141–146) reported on the utility of using computerized tomography (CT) as a diagnostic test for patients with clinically suspected appendicitis. In at least 20% of patients with appendicitis, the correct diagnosis was not made. On the other hand, the appendix was normal in 15% to 40% of patients who under- went emergency appendectomy. A study was designed to determine the prospective effectiveness of using CT as a diagnostic test to improve the treatment of these patients. The study examined 100 consecutive patients suspected of having acute appendicitis who presented to the emergency department or were referred there from a physician’s office. The 100 patients underwent a CT scan, and the surgeon made an assessment of the presence of appendicitis for each of the patients. The final clinical outcomes were determined at surgery and by pathological examination of the appendix after appendectomy or by clinical follow-up at least 2 months after CT scanning.
The 1996 rate of occurrence of appendicitis was approximately P(C) − .00108.
- a. Find the sensitivity and specificity of the radiological determination of appendicitis.
- b. Find the
probability that a patient truly had appendicitis given that the radiological determination was definitely appendicitis (DA). - c. Find the probability that a patient truly did not have appendicitis given that the radiological determination was definitely appendicitis (DA).
- d. Find the probability that a patient truly did not have appendicitis given that the radiological determination was definitely not appendicitis (DNA).
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Oishi and Shigehiro (2010) report that people who move from home to home frequently as children tend to have lower than average levels of well-being as adults. To further examine this relationship, a psychologist obtains a sample of n = 12 young adults who each experienced five or more different homes before they were 16 years old. These participants were given a standardized well-being questionnaire for which the general population has an average score of µ = 40. The well-being scores for this sample are as follows:
38, 37, 41, 35, 42, 40, 33, 33, 36, 38, 32, 39
On the basis of this sample, is well-being for frequent movers significantly different from well-being in the general population? Use a two-tailed test with α = .05.
The null hypothesis is H₀: .
Complete the following table.
M
SS
s²
sMM
t
Critical Values
Significant?
Compute the estimated Cohen’s d to measure the size of the difference.…
Colonoscopy is a medical procedure that is designed to find and remove precancerous lesions in the colon before they become cancerous. The article “Association of Colonoscopy and Death from Colorectal Cancer” (N. Baxter, M. Goldwasser, et al., Annals of Internal Medicine, 2009:1–8) reports that in a sample of 10,292 people diagnosed with colorectal cancer, 7.0% had previously had a colonoscopy, and in a sample of 51,460 people without colorectal cancer, 9.8% had previously had a colonoscopy. Can you conclude that the percentage of people who have had colonoscopies is greater in those without colorectal cancer?
Angioplasty is a medical procedure in which an obstructed blood vessel is widened. In some cases, a wire mesh tube, called a stent, is placed in the vessel to help it remain open. The article “Long-term Outcomes of Patients Receiving Drug-eluting Stents” (A. Philpott, D. Southern, et al., Canadian Medical Association Journal, 2009:167–174) presents the results of a study comparing the effectiveness of a bare metal stent with one that that has been coated with a drug designed to prevent reblocking of the vessel. A total of 5320 patients received bare metal stents, and of these, 841 needed treatment for reblocking within a year. A total of 1120 received drug coated stents, and 134 of them required treatment within a year. a) Find a 98% confidence interval for the differences between the proportions for drug coated stents and bare metal stents. b) Suppose that additional patients are to be treated in order to increase the precision of the confidence interval. Three sampling plans are…
Chapter 4 Solutions
An Introduction to Statistical Methods and Data Analysis
Ch. 4.18 - Indicate which interpretation of the probability...Ch. 4.18 - If you are having a stroke, it is critical that...Ch. 4.18 - In reporting highway safety, the National Highway...Ch. 4.18 - In a cable TV program concerning the risk of...Ch. 4.18 - The gaming commission in its annual examination of...Ch. 4.18 - The state vehicle inspection bureau provided the...Ch. 4.18 - The Texas Lottery has a game, Daily 4, in which a...Ch. 4.18 - A die is rolled two times. Provide a list of the...Ch. 4.18 - Refer to Exercise 4.10. Assume that the die is a...Ch. 4.18 - Refer to Exercise 4.11. a. Describe the event that...
Ch. 4.18 - Refer to Exercise 4.11. a. Are events A and B...Ch. 4.18 - A credit union takes a sample of four mortgages...Ch. 4.18 - A nuclear power plant has double redundancy on the...Ch. 4.18 - The population distribution in the United States...Ch. 4.18 - The makers of the candy MMs report that their...Ch. 4.18 - Refer to Exercise 4.11. Compute the following...Ch. 4.18 - Prob. 19ECh. 4.18 - Prob. 20ECh. 4.18 - Refer to Exercise 4.16. Let W be the event that...Ch. 4.18 - Is it possible for events A and B to be both...Ch. 4.18 - A survey of 1,000 U.S. government employees who...Ch. 4.18 - Refer to Exercise 4.23. Define the following...Ch. 4.18 - Prob. 25ECh. 4.18 - A large corporation has spent considerable time...Ch. 4.18 - The utility company in a large metropolitan area...Ch. 4.18 - Prob. 28ECh. 4.18 - Of a finance companys loans, 1% are defaulted (not...Ch. 4.18 - Refer to Exercise 4.29. Show that the posterior...Ch. 4.18 - Prob. 31ECh. 4.18 - In Example 4.4, compute the probability that the...Ch. 4.18 - Prob. 33ECh. 4.18 - In a January 15, 1998, article, the New England...Ch. 4.18 - Prob. 35ECh. 4.18 - Classify each of the following random variables as...Ch. 4.18 - Prob. 37ECh. 4.18 - Texting while driving is a very dangerous...Ch. 4.18 - Prob. 39ECh. 4.18 - The numbers of cars failing an emissions test on...Ch. 4.18 - A traditional call center has a simple mission:...Ch. 4.18 - A biologist randomly selects 10 portions of water,...Ch. 4.18 - Examine the accompanying newspaper clipping. Does...Ch. 4.18 - A survey is conducted to estimate the percentage...Ch. 4.18 - In an attempt to decrease drunk driving, police...Ch. 4.18 - The quality control department examines all the...Ch. 4.18 - Prob. 47ECh. 4.18 - The CFO of a hospital is concerned about the risk...Ch. 4.18 - Suppose the random variable y has a Poisson...Ch. 4.18 - Customers arrive at a grocery store checkout at a...Ch. 4.18 - A firm is considering using the Internet to...Ch. 4.18 - Prob. 52ECh. 4.18 - Prob. 53ECh. 4.18 - Prob. 54ECh. 4.18 - Prob. 55ECh. 4.18 - Prob. 56ECh. 4.18 - Prob. 57ECh. 4.18 - Prob. 58ECh. 4.18 - Prob. 59ECh. 4.18 - Prob. 60ECh. 4.18 - In Exercises 4.57 through 4.63, let z be a random...Ch. 4.18 - Prob. 62ECh. 4.18 - Prob. 63ECh. 4.18 - Prob. 64ECh. 4.18 - Let y be a random variable having a normal...Ch. 4.18 - Suppose that y is a random variable having a...Ch. 4.18 - Suppose that z is a random variable having a...Ch. 4.18 - Prob. 68ECh. 4.18 - Records maintained by the office of budget in a...Ch. 4.18 - The College Boards, which are administered each...Ch. 4.18 - Monthly sales figures for a particular food...Ch. 4.18 - Refer to Exercise 4.70. An honor society wishes to...Ch. 4.18 - Prob. 73ECh. 4.18 - Prob. 74ECh. 4.18 - A psychologist is interested in studying women who...Ch. 4.18 - Prob. 76ECh. 4.18 - A random sample of 16 measurements is drawn from a...Ch. 4.18 - Prob. 78ECh. 4.18 - Psychomotor retardation scores for a particular...Ch. 4.18 - Federal resources have been tentatively approved...Ch. 4.18 - Refer to Exercise 4.80. What size facility should...Ch. 4.18 - Based on the 1990 census, the number of hours per...Ch. 4.18 - The level of a particular pollutant, nitrogen...Ch. 4.18 - Refer to Exercise 4.83. A company has a fleet of...Ch. 4.18 - The baggage limit for an airplane is set at 100...Ch. 4.18 - A patient visits her doctor with concerns about...Ch. 4.18 - Critical key-entry errors in the data processing...Ch. 4.18 - Prob. 88ECh. 4.18 - Let y be a binomial random variable with n = 10...Ch. 4.18 - Prob. 90ECh. 4.18 - A marketing research firm advises a new client...Ch. 4.18 - Prob. 92ECh. 4.18 - Suppose a population consists of the 10...Ch. 4.18 - The fracture toughness in concrete specimens is a...Ch. 4.18 - One way to audit expense accounts for a large...Ch. 4.18 - The breaking strengths for 1-foot-square samples...Ch. 4.18 - Refer to Exercise 4.96. Suppose that a new...Ch. 4.18 - Refer to Exercise 4.97. Suppose that the mean...Ch. 4.18 - Prob. 99SECh. 4.18 - Prob. 100SECh. 4.18 - Experts consider high serum cholesterol levels to...Ch. 4.18 - Prob. 102SECh. 4.18 - Prob. 103SECh. 4.18 - Prob. 104SECh. 4.18 - Prob. 105SECh. 4.18 - Prob. 106SECh. 4.18 - Refer to Exercise 4.106. Plot the sampling...Ch. 4.18 - Random samples of size 5, 20, and 80 are drawn...Ch. 4.18 - Prob. 109SECh. 4.18 - Suppose the probability that a major earthquake...Ch. 4.18 - Prob. 111SECh. 4.18 - Airlines overbook (sell more tickets than there...Ch. 4.18 - Prob. 113SECh. 4.18 - As part of a study to determine factors that may...
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
- Sleep apnea is a disorder in which there are pauses in breathing during sleep. People with this condition must wake up frequently to breathe. The article “Postoperative Complications in Patients With Obstructive Sleep Apnea Syndrome Undergoing Hip or Knee Replacement: A Case-Control Study” (R. Gupta, J. Parvizi, et al., Mayo Clinic Proceedings, 2001:897–905) reported that in a sample of 427 people 65 and over, 104 of them had sleep apnea. a) Find a 95% confidence interval for the proportion of those 65 and over who have sleep apnea. b) Find a 99% confidence interval for the proportion of those 65 and over who have sleep apnea. c) Find the sample size needed for a 95% confidence interval to specify the proportion to within ±0.03. d) Find the sample size needed for a 99% confidence interval to specify the proportion to within ±0.03.arrow_forwardIn an observational study it was found that people who had received the flu shot this year had better blood pressure readings, on average, than people who did not. Can it be claimed that the flu shot is the cause of the lower overall blood pressure? Why or why not?arrow_forwardOishi and Schimmack (2010) report that people who move from home to home frequently as children tend to have lower than average levels of well-being as adults. To further examine this relationship, a psychologist obtains a sample of n = 12 young adults who each experienced 5 or more different homes before they were 16 years old. These participants were given a standardized well-being questionnaire for which the general population has an average score of μ = 40. The well-being scores for this sample are as follows: 38, 37, 41, 35, 42, 40, 33, 33, 36, 38, 32, 39. Report Cohen’s d value and interpret.arrow_forward
- In the article “Explaining an Unusual Allergy,” appearing on the Everyday Health Network, Dr. A. Feldweg explained that allergy to sulfites is usually seen in patients with asthma. The typical reaction is a sudden increase in asthma symptoms after eating a food containing sulfites. Studies are performed to estimate the percentage of the nation’s 10 million asthmatics who are allergic to sulfites. In one survey, 38 of 500 randomly selected U.S. asthmatics were found to be allergic to sulfites. Find and interpret a 95% confidence interval for the proportion p of all U.S. asthmatics who are allergic to sulfites.arrow_forwardOishi and Schimmack (2010) report that people who move from home to home frequently as children tend to have lower than average levels of well-being as adults. To further examine this relationship, a psychologist obtains a sample of n = 12 young adults who each experienced 5 or more different homes before they were 16 years old. These participants were given a standardized well-being questionnaire for which the general population has an average score of μ = 40. The well-being scores for this sample are as follows: 38, 37, 41, 35, 42, 40, 33, 33, 36, 38, 32, 39. a. On the basis of this sample, is well-being for frequent movers significantly different from wellbeing in the general population? Use a two-tailed test with α = .05. b. Compute the estimated Cohen’s d to measure the size of the difference. c. Write a sentence showing how the outcome of the hypothesis test and the measure of effect size would appear in a research report.arrow_forwardOishi & Shigehiro (2010) report that people who move from home to home frequently as children tend to have lower than average levels of well-being as adults. To further examine this relationship, a psychologist obtains a sample of n = 12 young adults who each experienced 5 or more different homes before they were 16 years old. These participants were given a standardized well-being questionnaire for which the general population has an average score of µ = 40. The well-being scores for this sample are as follows: 23, 37, 41, 35, 43, 37, 33, 34, 36, 38, 31, 38. On the basis of this sample, is well-being for frequent movers significantly different from the well-being of the general population? Test with alpha a = .05. Is this a one- %3D tailed or two-tailed test?arrow_forward
- A colonoscopy is a medical procedure that is designed to find and remove precancerous lesions in the colon before they become cancerous. The article “Association of Colonoscopy and Death from Colorectal Cancer” reports that in a sample of 10,292 people diagnosed with colorectal cancer, 7.1% had previously had a colonoscopy. In a sample of 51,460 people without colorectal cancer, 9.8% had previously had a colonoscopy. 25. Can you conclude that the percentage of people who have had colonoscopies is greater in those without colorectal cancer? Use ? = 0.01arrow_forwardOishi and Schimmack (2010) report that people who move from home to home frequently as children tend to have lower than average levels of well-being as adults. To further examine this relationship, a psychologist obtains a sample of n = 12 young adults who each experienced 5 or more different homes before they were 16 years old. These participants were given a standardized well-being questionnaire for which the general population has an average score of μ = 40. The well-being scores for this sample are as follows: 38, 37, 41, 35, 42, 40, 33, 33, 36, 38, 32, 39. A. On the basis of this sample, is well-being for frequent movers significantly different from wellbeing in the general population? Use a two-tailed test with α = .05. Is it significant? B. What type of error might you be making? C. Compute the estimated Cohen’s d to measure the size of the difference. D. Write a sentence showing how the outcome of the hypothesis test and the measure of effect size would appear in a research…arrow_forwardA magazine reported on the "... treatment-emergent adverse events that occurred in 2% or more patients treated with a new medicine and with incidence greater than placebo in the treatment of depression, OCD, or bulimia." In the study, patients took the new medicine and patients were given placebo. Identify the a. treatment group, b. control group, and c. treatments.arrow_forward
- A 2017 article in The New England Journal of Medicine details the results of a randomized clinical trial designed to evaluate the efficacy of a rotavirus gastroenteritis vaccine designed for infants. As per the authors: “Each year, rotavirus gastroenteritis is responsible for about 37% of deaths from diarrhea among children younger than 5 years of age worldwide, with a disproportionate effect in sub-Saharan Africa. We conducted a randomized, placebo-controlled trial in Niger to evaluate the efficacy of a live, oral bovine rotavirus pentavalent vaccine (BRV-PV, Serum Institute of India) to prevent severe rotavirus gastroenteritis. Healthy infants received three doses of the vaccine or placebo at 6, 10, and 14 weeks of age. Episodes of rotavirus gastroenteritis were assessed through active and passive surveillance.” The following Kaplan-Meier curves show the time to a diagnosis of rotavirus gastroenteritis separately for the vaccine and placebo samples. Infants were followed for up to 60…arrow_forwardOne study of cell phones and the risk of brain cancer looked at a group of 469 people who have brain cancer. The investigators then asked about the use of cell phones. Result: “Our data suggest that the use of hand- held cellular phones is not associated with risk of brain cancer. B . Based on this study, can you determine that cellular use does not CAUSE brain cancer? Why or why not?arrow_forwardThe fecal occult blood test, widely used both in physicians’ offices and at home to screen patients for colon and rectal cancer, examines a patient’s stool sample for blood, a condition indicating that cancer may be present. A recent study funded by the National Cancer Institute found that of 15,000 people tested on an annual basis, 10% were found to have blood in their stools. These 10% underwent further testing, including colonoscopy, the insertion of an optical-fiber tube through the rectum in order to inspect the colon and rectum visually for direct indications of cancer. Only 2.5% of those having colonoscopy actually had cancer. Additional information in the study suggests that, of the patients who were tested, approximately 5 out of 1,000 tested negative (no blood in the stool) but eventually did develop cancer. Create a probability table that shows the relationship between blood in a stool sample and colorectal cancer. Calculate P(Cancer|Blood) and P(Cancer|No Blood). The study…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
College Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
College Algebra (MindTap Course List)
Algebra
ISBN:9781305652231
Author:R. David Gustafson, Jeff Hughes
Publisher:Cengage Learning
Introduction to experimental design and analysis of variance (ANOVA); Author: Dr. Bharatendra Rai;https://www.youtube.com/watch?v=vSFo1MwLoxU;License: Standard YouTube License, CC-BY