Inference for a single Proportion: Comparing to a Known Proportion

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Choose which calculation you desire, enter the relevant values (as decimal fractions) for p0 (known value) and p1 (proportion in the population to be sampled) and, if calculating power, a sample size. You may also modify α (type I error rate) and the power, if relevant. After making your entries, hit the calculate button at the bottom.

  • Calculate Sample Size (for specified Power)
  • Calculate Power (for specified Sample Size)
    • Enter a value for p0:
    Enter a value for p1:
  • 1 Sided Test
  • 2 Sided Test
    • Enter a value for α (default is .05):
    Enter a value for desired power (default is .80):
    The sample size is:

    Reference: The calculations are the customary ones based on the normal approximation to the binomial distribution. See for example Hypothesis Testing: One-Sample Inference - One-Sample Inference for a Binomial Proportion in Bernard Rosner's Fundamentals of Biostatistics


    Rollin Brant
    Email me at: rollin@stat.ubc.ca