Question

Assume that 0.4% of the population has a condition that is not detectible by simple external...

Assume that 0.4% of the population has a condition that is not detectible by simple external observation. A diagnostic test is available for this condition, but, like most tests, it is not perfect. The test correctly diagnoses, with a positive result, those with the condition 99.7% of the time. The test correctly identifies, with a negative result, those without the condition 98.5% of the time.

  1. Let the event C1 represent the presence of the condition and C2 represent the absence of the condition, and let event T represent a positive test result (meaning the test indicated, either correctly or incorrectly, that a person has the condition) and TC represent a negative test result (meaning the test indicated, either correctly or incorrectly, that a person does not have the condition). List symbolically the information given in the introductory statement at the top of the page.

                            

  1. If a randomly selected member of the population tests positive for the condition, what is the probability that the person has the condition? (Report or round your answer to 3 decimal places.)

                      Find:

                      Formula(s):

                      Computations:

                      Answer:

  1. If a randomly selected member of the population tests positive for the condition, what is the probability that the person does not have the condition?
  1. If a randomly selected member of the population tests negative for the condition, what is the probability that the person has the condition? (Report or round your answer to 6 decimal places.)

    Assume that 0.4% of the population has a condition that is not detectible by simple external observation. A diagnostic test is available for this condition, but, like most tests, it is not perfect. The test correctly diagnoses, with a positive result, those with the condition 99.7% of the time. The test correctly identifies, with a negative result, those without the condition 98.5% of the time.

  2. Let the event C1 represent the presence of the condition and C2 represent the absence of the condition, and let event T represent a positive test result (meaning the test indicated, either correctly or incorrectly, that a person has the condition) and TC represent a negative test result (meaning the test indicated, either correctly or incorrectly, that a person does not have the condition). List symbolically the information given in the introductory statement at the top of the page.
  3.                             

  4. If a randomly selected member of the population tests positive for the condition, what is the probability that the person has the condition? (Report or round your answer to 3 decimal places.)
  5.                       Find:

                          Formula(s):

                          Computations:

                          Answer:

  6. If a randomly selected member of the population tests positive for the condition, what is the probability that the person does not have the condition?
  7. If a randomly selected member of the population tests negative for the condition, what is the probability that the person has the condition? (Report or round your answer to 6 decimal places.)

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