search for: _of_params

Hey, I make a regression for Gamma distribution with log link, in R and in SAS. In R, the dispersion is estimated by \phi=Deviance/(#_of_observations), In SAS, there are two options: \phi=Deviance/(#_of_observations-#_of_params) or \phi=Pearson/(#_of_observations-#_of_params). I understand that SAS formulae are correct, however, the coefficients, obtained by R and by the first version of SAS, are equal, and the difference is only in standard errors of betas. Could anyone explain me the phenomenon? Maybe, there is smth. a...