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Hi Tassos, my personal opinion is, that I would like to see the usual phasing statistics. At least to me, they provide hints how well the structure was determined, analogous to the R-factor/Free-R-factor providing hints how well the structure was refined. It would be good if SHELXE would print out those statistics before any density modification. Best regards, Dirk. Am 12.04.10 13:10, schrieb Anastassis Perrakis: > Hi - > > A year or so ago, I have asked as a referee somebody to provide for a > paper the statistics for their heavy atom derivative dataset, > and for the phasing statistics. For some good reasons, they were > unable to do that, and they (politely) asked me > 'what would it change if you knew these, isn't the structure we > present impeccable?'. Well, I think they were right. > Their structure was surely correct, surely high quality. After that > incident and giving it some thought, > I fail to see why should one report e.g. PP or Rcullis, or why will I > care what they were if the structure has a convincing Rfree and is > properly validated. > If someone wants to cheat at the end of the day, its easy to provide > two numbers, but its hard to provide a good validated model that > agrees with the data. > (and, yes, you can also make up the data, but we have been there, > haven't we?!?) > > So, my question to that referee, likely being a ccp4bb aficionado that > is reading this email, or to anyone else really, is: > > "What would it help to judge the quality of the structure or the paper > if you know PP, Rcullis and FOM?" > > Best - > > A. > > PS Especially since you used SHELXE for phasing these statistics are > utterly irrelevant, and possibly you could advice the referee to read > a bit about how SHELXE works ... or go to one of the nice courses that > George teaches ... > > On Apr 12, 2010, at 10:37, Eleanor Dodson wrote: > >> You can feed the SHELX sites into phaser_er or CRANK both of which will >> give this sort of information. >> >> Or mlphare if you know how to set it up.. >> >> Eleanor >> >> >> Harmer, Nicholas wrote: >>> Dear CCP4ers, >>> >>> I've been asked by a referee to provide the phasing statistics for a >>> SAD dataset that I used to solve a recent structure. Whilst I have >>> been able to find a figure-of-merit for the data after phasing, I >>> can't work out how to get any other statistics (e.g. phasing power >>> or an equivalent or Rcullis). Does anyone know a good route to >>> obtaining useful statistics to put in the paper for SAD data? >>> >>> The structure solution was carried out using SHELX C/D/E and then >>> ARP/wARP. >>> >>> Thanks in advance, >>> >>> Nic Harmer >>> >>> ===================== >>> Dr. Nic Harmer >>> School of Biosciences >>> University of Exeter >>> tel: +44 1392 725179 >>> > > *P** **please don't print this e-mail unless you really need to* > Anastassis (Tassos) Perrakis, Principal Investigator / Staff Member > Department of Biochemistry (B8) > Netherlands Cancer Institute, > Dept. B8, 1066 CX Amsterdam, The Netherlands > Tel: +31 20 512 1951 Fax: +31 20 512 1954 Mobile / SMS: +31 6 28 597791 > > > > -- ******************************************************* Dirk Kostrewa Gene Center, A 5.07 Ludwig-Maximilians-University Feodor-Lynen-Str. 25 81377 Munich Germany Phone: +49-89-2180-76845 Fax: +49-89-2180-76999 E-mail: [log in to unmask] WWW: www.genzentrum.lmu.de *******************************************************