Confidence Intervals > Clopper-Pearson
The Clopper-Pearson interval, also called the exact interval is an alternative to calculating binomial confidence intervals using normal approximation. It is based on inverting the equal-tailed binomial tests. It is the most commonly cited exact method for finding a confidence interval .
The Clopper-Pearson exact method is strictly conservative and therefore considered to be exact. As the method is conservative, it may not give the shortest possible interval containing the desired confidence interval . This is especially true when you know the population size. Although the Clopper-Pearson exact method was intended to have a minimum coverage of 95% , in the majority of cases the coverage can exceed 99%.
Clopper-Pearson Exact Method Formula
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