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CPS2099 Takatsugu Yoshioka et al.
                                                 Table 1
                                 Upper percentiles and type I error rate
                                            α=0.05                      α=0.01
                     N1     N2     T2      F     α1     α2     T2      F     α1     α2
                     10     10    15.16   14.54   0.162   0.057   25.22   22.82   0.073   0.015
                     20     20    13.43   13.23   0.131   0.053   21.03   20.25   0.049   0.012
                     40     40    11.12   11.10   0.086   0.050   16.68   16.21   0.027   0.012
                     80     80    10.31   10.24   0.067   0.050   14.29   14.63   0.016   0.010
                                           2
                      Note : (0.05) = 9.49,  (0.01) = 13.28
                             2
                                           4
                             4

               4.  Discussion and Conclusion
                   In  this  study,  we  have  developed  the  approximate  distribution  of
               Hotelling’s  T   type  test  statistics  by  a  constant  times  an  F  distribution  by
                            2
               adjusting the degrees of freedom. The method of adjusting the degrees of
               freedom is estimated unknown parameters of the degrees of freedom of the
               F distribution using the asymptotic expansion of the Hotelling’s T  type test
                                                                                2
               statistic.  The  approximate  values  can  be  calculated  easily  and  the
               approximation is much better than the chi-squared approximation, even when
               the sample size is small.

               References
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