A person has a cough and flu-like symptoms and gets a PCR test for COVID-19, which comes back positive. What is the likelihood that they actually have COVID-19, as opposed to a regular cold or flu? Let’s say that the local rate of symptomatic individuals who actually are infected with COVID-19 is 11%; The RT-PCR test used to identify COVID-19 RNA is highly specific (that is, it very rarely reports the presence of the virus when it is not present); for our example, we will say that the specificity is 95%. Its sensitivity is not known but probably is no higher than 90%.

A person has a cough and flu-like symptoms and gets a PCR test for COVID-19, which comes back positive. What is the likelihood that they actually have COVID-19, as opposed to a regular cold or flu? Let’s say that the local rate of symptomatic individuals who actually are infected with COVID-19 is 11%; The RT-PCR test used to identify COVID-19 RNA is highly specific (that is, it very rarely reports the presence of the virus when it is not present); for our example, we will say that the specificity is 95%. Its sensitivity is not known but probably is no higher than 90%.

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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