Re: [ccp4bb] Counting of geometrical restraints?

Hi Pete Not sure what you mean by 'which parameters'. We're talking here about the total parameter _count_ and its effect on the statistics, i.e. R factors etc. You can't relate a specific parameter to a specific restraint. The statistics behave in exactly the same way as they would if you did

Re: [ccp4bb] Counting of geometrical restraints?

Ian, Now it's still true that Ncon reduces Npar but it's no longer true that Ncon increases Nobs. This seems counter-intuitive enough for me to ask a stupid question: which parameters are being removed in restrained refinement? For constraints this seems straightforward (transformation of >

Re: [ccp4bb] Counting of geometrical restraints?

Hi Dirk I think cross-validation changed our ideas! Pre-Rfree the statistics of refinement was concerned with the 'number of degrees of freedom': Ndof = Nobs - N'par since this is the expectation of the properly weighted least-squares residual (chi-square or in the paper). If

[ccp4bb] Counting of geometrical restraints?

Dear Ian & other CCP4ers, I want to get a riddle about counting geometrical restraints solved, which emerged in my head after a recent discussion on this board about the effect of NCS on the data:parameter ratio. This discussio