stefano.ciurli at unibo.it
Tue Aug 24 10:43:24 CDT 2004
> > When it comes down to compare fits using different models, which is
>> the relevant parameter? Chi square (and reduced) or R-factor? I have
>> fits with smaller chi square and larger Rfactor and viceversa...
>This is definitely a FAQ, so I put the answer at
> > Is it possible that a rationale would be that when the models to
>> compare have the same number of atoms these parameters go in
>> parallel? And that when the number of atoms is different one must
>> rely more on chi square rather than R-factor (or viceversa)?
>I'm not sure I understnad this: I'd say the number of atoms or
>paths, or anything else that describes the complexity of the
>model, is NOT important. What's important is how well the
>specified variables cause the model to match the data.
I think here below is the answer I was looking for (taken from the link above):
Either of these parameters can be used to compare different fits if
the number of varibles and data k- and R-ranges are the same for the
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