Concept explainers
The value of mammography as a screening test for breast cancer has been controversial, particularly among young women. A study was recently performed looking at the rate of false positives for repeated screening mammograms among approximately 10,000 women who were members of Harvard Pilgrim Health Care, a large health-maintenance organization in New England [9].
The study reported that of a total of 1996 tests given to 40- to 49-year-old women, 156 yielded false-positive results.
Provide a two-sided 95% CI for the
Suppose a woman is given a mammogram every 2 years starting at age 40. What is the probability that she will have at least one false-positive test result among 5 screening tests during her forties? (Assume the repeated screening tests are independent.)
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- What is an experiment?arrow_forwardAnnie is concerned over a report that "a woman over age 40has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 40-year-old university-educated American woman was 3.4%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 407 never-previously-wed, university-educated, American women who were single at the beginning of their 40s and who are now 45. Of these women, 20 report now being married. Does this evidence support Annie’s claim, at the 0.01 level of significance, that the chances of getting married for this group is greater than 3.4%? Step 3 of 3 : Draw a conclusion and interpret the decision.arrow_forwardA 2016 Pew Research poll found that 18% of cell phone owners use their phone for conducting transactions with their bank. Let’s assume that 0.18 is the true proportion (in 2016) of all cell phone owners who use their cell phone for banking. (a) You take a random sample of 150 current cell phone owners and find that 38 of them use their cell phone for banking. Is this convincing evidence that since 2016 there has been an increase from 0.18 in the proportion of cell phone owners who use their cell phone for banking? Use = 0.05. (b) Suppose the question you asked the people in your sample was, “People on the go use their cell phone for everything. Do you ever use yours to conduct your banking business?” Comment on the potential bias arising from the way this question was asked and its’ impact on your conclusion.arrow_forward
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- Annie is concerned over a report that "a woman over age 40 has a better chance of being killed by a terrorist than of getting married." A study found that the likelihood of marriage for a never-previously-wed, 40-year-old university-educated American woman was 3.1%. To demonstrate that this percentage is too small, Annie uses her resources at the Baltimore Sun to conduct a simple random sample of 494 never-previously-wed, university-educated, American women who were single at the beginning of their 40s and who are now 45. Of these women, 22 report now being married. Does this evidence support Annie’s claim, at the 0.02 level of significance, that the chances of getting married for this group is greater than 3.1%?Step 2 of 3 : Compute the value of the test statistic. Round your answer to two decimal places.arrow_forwardA survey recently reported that the mean national annual expenditure for inpatient andoutpatient services of all persons over 64 years of age was $5,423 with a standarddeviation of $979. A random sample of 352 persons over age 64 living in Sudbury had anaverage expense of $5,516. We want to test whether the mean inpatient and outpatient expense of all Sudbury residents over age 64 is higher than the national average of $5,423. Calculate the P-value for this test.arrow_forwardA study is designed to test whether there is a difference in mean daily calcium intake in adults with normal bone density, adults with osteopenia (a low bone density which may lead to osteoporosis) and adults with osteoporosis. Adults 60 years of age with normal bone density, osteopenia and osteoporosis are selected at random from hospital records and invited to participate in the study. Each participant's daily calcium intake is measured based on reported food intake and supplements. The data are shown below. Is there a statistically significant difference in mean calcium intake in patients with normal bone density as compared to patients with osteopenia and osteoporosis?arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillCollege Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning