A disease afflicts 1 person in 10 in a population. A test for this disease results in 5% false positives. Assume that a random person is tested for the disease (this person is not selected for the test because there are other symptoms indicating the presence of the disease nor are there any special signs of being disease free). Assume that there are no false negatives from this test. A person tests positive. What is the probability that the person truly has the disease? Now assume that false negatives are 15%. What is the probability that the person truly has the disease? The following paragraph is taken from the National Cancer Institute’s web site on the PSA test for prostate cancer. The paragraph is the complete discussion of false positive PSA results offered on the web site.

A disease afflicts 1 person in 10 in a population. A test for this disease results in 5% false positives. Assume that a random person is tested for the disease (this person is not selected for the test because there are other symptoms indicating the presence of the disease nor are there any special signs of being disease free). Assume that there are no false negatives from this test. A person tests positive. What is the probability that the person truly has the disease? Now assume that false negatives are 15%. What is the probability that the person truly has the disease? The following paragraph is taken from the National Cancer Institute’s web site on the PSA test for prostate cancer. The paragraph is the complete discussion of false positive PSA results offered on the web site.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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