[phenixbb] Table 1 stastics
nechols at lbl.gov
Fri Oct 19 08:15:11 PDT 2012
On Fri, Oct 19, 2012 at 8:07 AM, Kay Diederichs
<Kay.Diederichs at uni-konstanz.de> wrote:
> I just want to point out that one possible source of discrepancy between
> I/sigma reported by a data processing program, and I/sigma reported by a
> program that uses the relevant cctbx routine is the following: that cctbx
> routine calculates the variance of merged data as max("internal variance",
> "external variance") which is different from what the data processing
> programs do (they calculate the "internal variance" - I hope I didn't get it
> the wrong way round). SHELXC and SHELXL also calculate the variance of the
> merged data like the data processing programs do.
Good point. However, this particular CCTBX routine is only used when
merging non-unique data, which would not be the typical input here (at
least in the official release).
> I dislike this "feature" of cctbx but I do not know if phenix.table_one
> actually uses this routine for this purpose.
It does. But I may change this, if I can be certain it won't screw
things up for the small molecule folks. I'm just not sure why it was
written that way in the first place...
More information about the phenixbb