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    A probability question



    I am trying to revise for a test, and am working through some prep questions. I am struggling on this one, could anyone help?

    Suppose there is a medical diagnostic test for a disease. The sensitivity of the
    test is .95. This means that if a person has the disease, the probability that the
    test gives a positive response is .95. The specificity of the test is .90. This
    means that if a person does not have the disease, the probability that the test
    gives a negative response is .90, or that the false positive rate of the test is .10.
    In the population, 1% of the people have the disease.
    What is the probability that a person tested has the disease, given the results of the test is positive? Let
    D be the event "the person has the disease" and let T be the event "the test
    gives a positive result."

    Any help would be much appreciated.

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    RotParaTon
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    Re: A probability question

    Do you know Bayes theorem?
    "His programming is malfunctioning. It begins! Get your weapons, he's going to become a killbot!!!" - bryangoodrich

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    Re: A probability question

    I do, im just getting muddled up with the wording of the question so I keep confusing myself

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    Re: A probability question

    Using the events they gave you (D be the event "the person has the disease" and let T be the event "the test gives a positive result.") can you write out all the information they gave you? What probability are you looking for?
    "His programming is malfunctioning. It begins! Get your weapons, he's going to become a killbot!!!" - bryangoodrich

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    Re: A probability question


    I figured it out in the end just took a little while to wrap my head round the wording. Sorry for the inconvenience

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