11 Jul
2011
11 Jul
'11
9:34 p.m.
what is the common practice with respect to how many significant figures should be used for reporting Rfree If you look up crystallographic papers, you'll find that people routinely report R-values with 3 significant digits, i.e. 23.4% and such. The fourth digit is unreliable - try refining against the same dataset with different test set and you'll find that the Rfree varies within at least 0.1% (depending on resolution, data quality, etc).
You don't even need to change the test set to see that even the third one is not reliable too: pages 75-77 here: http://www.phenix-online.org/presentations/latest/pavel_refinement_general.p... Pavel.