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4.4.1: Exercises

  • Page ID
    83582
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    1. A certain disease has an incidence rate of 0.3%. If the false negative rate is 6% and the false positive rate is 4%. Set up a two way table with a sample size of 10,000 people.
      1. Compute the probability that a person who tests positive actually has the disease.
      2. Compute the probability that a person who tests negative actually has the disease.
      3. Compute the probability that a person who has the disease tests negative.
      4. Compute the probability that a person who does not have the disease tests negative.
    2. A certain disease has an incidence rate of 0.1%. If the false negative rate is 8% and the false positive rate is 3%. Set up a two way table with a sample size of 10,000 people.
      1. Compute the probability that a person who tests positive does NOT have the disease.
      2. Compute the probability that a person who tests negative does NOT have the disease.
      3. Compute the probability that a person who has the disease tests positive.
      4. Compute the probability that a person who does not have the disease test positive.
    3. A certain group of symptom-free women between the ages of 40 and 50 are randomly selected to participate in mammography screening. The incidence rate of breast cancer among such women is 0.8%. The false negative rate for the mammogram is 10%. The false positive rate is 7%. If a the mammogram results for a particular woman are positive (indicating that she has breast cancer), what is the probability that she actually has breast cancer?
    4. About 0.01% of men with no known risk behavior are infected with HIV. The false negative rate for the standard HIV test 0.01% and the false positive rate is also 0.01%. If a randomly selected man with no known risk behavior tests positive for HIV, what is the probability that he is actually infected with HIV?

    This page titled 4.4.1: Exercises is shared under a not declared license and was authored, remixed, and/or curated by Leah Griffith, Veronica Holbrook, Johnny Johnson & Nancy Garcia.

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