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Re: [ccp4bb]: Phasing Phoiled by Phistats in Philadelphia. Pfui.
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"Patrick J. Loll" wrote:
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> I'm confused about output I obtain from phistats. I'm attempting to
> calculate the phase errors associated with various phasing procedures.
> I've written a little program to calculate the quantity:
> <|deltaPhi|> = the mean value over all reflxns of the absolute value of the
> difference between Phi1 and Phi2. I calculate this for all
> reflxns and for acentrics only
I dont think phistats is wrong but will check.
Do you always convert the difference to lie in the range 0-180?
ie if one phase is 10 and the other 350, then the difference is 20 not
The best test is that two sets of random phases should differ by 90 ..
But a plug for phistats:
the unweighted phase difference doesnt mean much if the FOMs are ~ 0.00
the weighted diff is more meaningful.