CONFIDENCE-INTERVAL-PROPORTION (X N CONFIDENCE)
Suppose we have a sample of `n' things and `x' of them are ``successes.'' We can estimate the population proportion of successes as x/n; call it `p-hat.' This function computes the estimate and a confidence interval on it. This function is not appropriate for small samples with p-hat far from 1/2: `x' should be at least 5, and so should `n'-`x.' This function returns three values: p-hat, and the lower and upper bounds of the confidence interval. `Confidence' should be a number between 0 and 1, exclusive.