Many times in statistical analysis you may need to know if a population mean is significantly different from some reference value. This is a type of -test if the population variance is not known. The Wolfram Language contains several functions to test hypotheses for population means.
You can also use TTest to decide whether the difference between two population means differs significantly from an assumed value. In this case, the null hypothesis is that the population means are equal (differ by 0):
Tests can also be done for paired comparisons of datasets. This can be done by using PairedTTest on the pairwise differences: