Jackie

I agree completely with Ed (for once!), not only for the reasons he
gave, but also that it's valid to compare statistics such as
likelihood and R factors ONLY if only the model is varied.  Such a
comparison is not valid if the data used are varied (in this case you
are changing the data by deleting some of them).

Cheers

-- Ian

On Tue, Oct 26, 2010 at 2:37 PM, Ed Pozharski <[email protected]> wrote:
> Jackie,
>
> please note that (at least imho) the desire to obtain "better" R-factors
> does not justify excluding data from analysis.  Weak reflections that
> you suggest should be rejected contain information, and excluding them
> will indeed artificially lower the R-factors while reducing the accuracy
> of your model.
>
> Cheers,
>
> Ed.
>
> On Mon, 2010-10-25 at 17:44 -0400, Jacqueline Vitali wrote:
>> Also if your Rmerge is high and you include all reflections in
>> refinement, Rfree is high.  In my experience, by excluding F < sigma
>> reflections you drop Rfree a lot.
>
>
>
> --
> "I'd jump in myself, if I weren't so good at whistling."
>                               Julian, King of Lemurs
>

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