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Birthday Problem with Realistic Assumptions

  1. Jul 21, 2011 #1
    Hi, All:

    The standard way of approaching the birthday problem, i.e., the problem of
    determining the number of people needed to have a certain probability that
    two of them have the same birthday, is based on the assumption that birthdays
    are uniformly-distributed, i.e., that the probability of someone having a birthday
    on a given day is 1/365 for non-leap, or 1/366 for leap.

    But there is data to suggest that this assumption does not hold; specifically,
    this assumption failed a chi-square at the 95% for expected-actual, for n=480,040
    data points.

    Does anyone know of a solution that uses a more realistic distribution of birthdates?
  2. jcsd
  3. Jul 21, 2011 #2
    This paper seems to be exactly what you're looking for--


    but you will need access to a JSTOR account to see more than the first page.
    Last edited by a moderator: Apr 26, 2017
  4. Jul 22, 2011 #3
    Excellent, 'Awkward' , thanks.
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