t-Tests & Procedures
t-Tests for the Significance of the Difference between the Means of Two Samples.T
The first of these pages is somewhat more streamlined than the other two. It will also more comfortably handle large sample sizes. Although the other pages are somewhat clunkier, their data-entry format might prove more fail-safe for the beginning student. As the latter two pages open, you will be prompted to enter the size of your samples.
t-Test for Independent or Correlated SamplesT
[Traducción en español]T
t-Test for Independent Samples [cell-entry format]T
t-Test for Correlated Samples [cell-entry format]
For non-parametric alternatives to the independent and correlated samples t-tests, see the Mann-Whitney Test and the Wilcoxon Signed-Ranks Test under Ordinal Data. For small samples, see also 'Resampling Probability Estimates ...' under Miscellanea.
Single Sample t-Test. For the significance of the difference between the observed mean of a sample and a hypothetical mean of the population from which the sample is randomly drawn. As the page opens, you will be prompted to enter the size of your sample.
.95 and .99 Confidence Intervals for the Estimated Mean of a Population. Given a sample of N values of X, randomly drawn from a normally distributed population, this page will calculate the .95 and .99 CIs for the estimated mean of the population.