One Sample T Confidence Intervals

The R function t.test (on-line help) does t tests and confidence intervals.

does the example on the slides for class.

This example can also be done reading the data from a URL

Two Sample T Confidence Intervals

The R function t.test also does two-sample tests.

Assuming Equality of Variances

does the example on the slides for class.

Welch's Approximation

does the example on the slides for class.