  A sample of 286 gamma-ray bursts, detected by Swift satellite, is studied
statistically by the chi^2 test and the Student t-test, respectively. The short
and long subgroups are well detected in the Swift data. But no intermediate
subgroup is seen. The non-detection of this subgroup in the Swift database can
be explained, once it is assumed that in the BATSE database the short and the
intermediate subgroups form a common subclass.
