The Welch-James procedure may be used to test hypotheses on means, when independent samples from populations with heterogeneous variances are available. Until recently the complexity of the available presentations of this procedure limited the application of this procedure. To resolve this state of affairs, summation formulas for the Welch-James procedure are presented for the 2 x 2 design. In addition, matrix formulas that permit routine application of the procedure to crossed factorial designs are presented.
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