ABSTRACT
We often have two independent random samples. That is, samples in which members of the first sample, or group, are independent of each other and are independent of those in the second. We want to make inferences about the two populations from which the samples are drawn. We denote the observations in the samples by x1, x2, . . . , xm and y1, y2, . . . , yn, where, for convenience and without loss of generality, we assume n ≥ m, i.e., that the second sample is at least as large as the first.
