CONFIDENCE-INTERVAL-T (DATA CONFIDENCE)
Suppose you have a sample of 10 numbers and you want to compute a 90 percent confidence interval on the population mean. This function is the one to use. This function uses the t-distribution, and so it is appropriate for small sample sizes. It can also be used for large sample sizes, but the function `confidence-interval-z' may be computationally faster. It returns three values: the mean and the lower and upper bound of the confidence interval. True, only two numbers are necessary, but the confidence intervals of other statistics may be asymmetrical and these values would be consistent with those confidence intervals. `Sample' should be a sequence of numbers. `Confidence' should be a number between 0 and 1, exclusive.