Confidence interval calculators

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I’m not sure when I first started mounting these calculators, certainly by 2003. These compute the confidence interval (CI) for observed sample statistics using the sample statistics and the sample size. The default CI is 95% but you can set other spreads if you want them. For continuous value statistics these are parametric model CIs based on Gaussian distributions, for rates these are the best performing methods for the CIs as far as I can work out from R documentation and my reading).