An Introduction to Statistical Methods and Data Analysis
7th Edition
ISBN: 9781305269477
Author: R. Lyman Ott, Micheal T. Longnecker
Publisher: Cengage Learning
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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).
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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...
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