## Function Confidence-Interval-T

(

**confidence-interval-t** &rest < args > )

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:<br> the mean and the lower and upper bound of the confidence interval. True, only<br> two numbers are necessary, but the confidence intervals of other statistics may<br> be asymmetrical and these values would be consistent with those confidence<br> intervals. `

Sample' should be a sequence of numbers. `Confidence' should be a

number between 0 and 1, exclusive.