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Poisson Approximation to Binomial

  1. Mar 22, 2005 #1
    For a binomial distribution with n=10 and p=0.5 ,we should not use the poisson approximation because both of the conditions n>=100 and np<=10 are not satisfied. SUppose we go way out on a limb and use the Poisson aproximation anyway. Are the resulting probabilities unacceptable approximations? Why or why not ?
  2. jcsd
  3. Mar 22, 2005 #2


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    Have you worked out the actual value and the approximation?
  4. Mar 22, 2005 #3
    n=10, p=1/2, x=1, mean=n*p= 5

    using the poisson formula i got 3.4%
    using binomial formula I got 1%
    using (mean)+/- 2(standard deviation) i got 8.4 - 1.8

    I dont know If its right, confused because should'nt the binomial furmula give the answer within the maximum and minumum usual values ?
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