A sample of 197 long BATSE GRBs is studied statistically. In the sample 11
variables, describing for any burst the time behavior of the spectra and other
quantities, are collected. The application of the factor analysis on this
sample shows that five factors describe the sample satisfactorily. Both the
pseudo-redshifts coming from the variability and the Amati-relation in its
original form are disfavored.Comment: In GAMMA-RAY BURSTS 2007: Proceedings of the Santa Fe Conferenc
