On Jan 10, 2012, at 22:00 , Jacob Keller wrote: > Dear Crystallographers, > > it seems to me that on a certain level we are always throwing away > (sort of) about half of our data when we merge Bijvoet pairs--why
Who "We" ? > shouldn't we keep them separate, since we know that they should be a > little bit different, especially in light of the higher multiplicities > which are more common now? Shouldn't modelling them give better > R-values, and wouldn't it just be more true? I guess a sort of proof > for this is that sulfurs are almost always detectable on anomalous As a matter of protocol, for the last 25 years I keep anomalous signal in my data for refinement, does not matter what ignorant annotators say. I do it for several reasons, one of them is matter of principle. > difference maps, implying that we are actually measuring those > differences accurately enough to see them (I don't think these things The problem is sometimes to deposit the data, which were used for the refinement. Developers refuse to add the redundant information into the deposition file, annotators refuse to accept the data file without averaged value for F or I, directors keep silent. Be strong Jacob... > can arise from model bias, as anomalous differences are not modeled.) > At least maybe at the final steps of refinement...? > > JPK > > -- > ******************************************* > Jacob Pearson Keller > Northwestern University > Medical Scientist Training Program > email: j-kell...@northwestern.edu > ******************************************* Dr Felix Frolow Professor of Structural Biology and Biotechnology Department of Molecular Microbiology and Biotechnology Tel Aviv University 69978, Israel Acta Crystallographica F, co-editor e-mail: mbfro...@post.tau.ac.il Tel: ++972-3640-8723 Fax: ++972-3640-9407 Cellular: 0547 459 608