.…but there is a difference whether I measure the same identical hkl over again 
or ‘preferably in more than one symmetry-equivalent position’, to quote the

IUCr. So do we have a MPSR for the same reflection and a MPRR for the related 
reflections?

 

Cacophonically yours,

 

BR

 

From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> On Behalf Of John R Helliwell
Sent: Tuesday, June 30, 2020 08:36
To: CCP4BB@JISCMAIL.AC.UK
Subject: Re: [ccp4bb] [EXTERNAL] Re: [ccp4bb] number of frames to get a full 
dataset?

 

Dear Herman,

I think that MPR is a very neat and tidy, excellent, proposal.

Moreover it uses the word “measurements”, and we are an experimental based 
science.

I support it.

Great.

Greetings,

John 

Emeritus Professor John R Helliwell DSc

 

 

 

 

On 30 Jun 2020, at 15:10, Schreuder, Herman /DE <herman.schreu...@sanofi.com 
<mailto:herman.schreu...@sanofi.com> > wrote:

 

Dear BB,

 

Since there does not seem a generally accepted term for the subject of this 
discussions, and since even the IUCR scriptures do not give any guidance, I 
would propose to introduce a completely new term:

 

Measurements per reflection or MPR

 

This term is politically neutral, should adequately describe this particular 
statistic and is not associated with entrenched traditions at either side of 
the Atlantic.

 

What do you think?

Herman

 

 

Von: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK <mailto:CCP4BB@JISCMAIL.AC.UK> 
> Im Auftrag von John R Helliwell
Gesendet: Dienstag, 30. Juni 2020 14:34
An: CCP4BB@JISCMAIL.AC.UK <mailto:CCP4BB@JISCMAIL.AC.UK> 
Betreff: [EXTERNAL] Re: [ccp4bb] number of frames to get a full dataset?

 

EXTERNAL : Real sender is owner-ccp...@jiscmail.ac.uk 
<mailto:owner-ccp...@jiscmail.ac.uk>  

 

Dear Colleagues,

In an effort to break this naming deadlock, and with Massimo and Ian not 
showing up as yet, I checked the IUCr Dictionary.

“Redundancy“ and “Multiplicity“ are not listed.

The more generic term “Statistical Descriptors“ is though and even offers 
Recommendations:-

http://ww1.iucr.org/iucr-top/comm/cnom/statdes/recomm.html 
<https://urldefense.proofpoint.com/v2/url?u=http-3A__ww1.iucr.org_iucr-2Dtop_comm_cnom_statdes_recomm.html&d=DwMFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=-45HByHsLJPmc2KRmPKamiFNf1WFCI51GonllFyIRTE&e=>
 

Point 1, first sentence, fits the various wishes of this thread succinctly, if 
not in a single word, and even not readily allowing an easy acronym. 

Greetings,

John 

 

Emeritus Professor John R Helliwell DSc

 

 





On 30 Jun 2020, at 13:11, Phil Jeffrey <pjeff...@princeton.edu 
<mailto:pjeff...@princeton.edu> > wrote:

The people that already use multiplicity are going to find reasons why it's 
the superior naming scheme - although the underlying reason has a lot to do 
with negative associations with 'redundant', perhaps hightened in the current 
environment.  And conversely redundant works for many others - Graeme's 
pragmatic defense of multiplicity actually works both ways - any person who 
takes the trouble to read the stats table, now exiled to Supplementary Data, 
knows what it means.  Surely, then, the only way forward on this almost totally 
irrelevant discussion is to come up with a universally-loathed nomenclature 
that pleases nobody, preferably an acronym whose origins will be lost to 
history and the dusty CCP4 archives (which contain threads similar to this 
one).  I humbly submit:

NFDOF: Nearly Futile Data Overcollection Factor ?
[*]

Or, even better, could we not move on to equally pointless discussions of the 
inappropriateness of "R-factor" ?  I have a long history of rearguard action 
trying to give stupid acronyms a wider audience, so you're guaranteed to hear 
from me on this for years.

(Personally I'm pining for Gerard Kleywegt to resume his quest for overextended 
naming rationales, of which ValLigURL is a personal 'favo[u]rite'.  But I'm 
just old-fashioned.)

Ironically,
Phil Jeffrey
Princeton

[* I too have collected 540 degrees in P1 to solve a SAD structure, just 
because I could, hence "nearly"]
[** The actual answer to this thread is: history is written by the authors of 
scaling programs - and I think the Americans are currently losing at this game, 
thus perilously close to making themselves redundant.]

On 6/30/20 4:14 AM, Winter, Graeme (DLSLtd,RAL,LSCI) wrote:



Or, we could accept the fact that crystallographers are kinda used to 
multiplicity of an individual Miller index being different to multiplicity of 
observations, and in Table 1 know which one you mean? 😉 Given that they add new 
information (at the very least to the scaling model) they are strictly not 
“redundant”.

The amount that anyone outside of methods development cares about the “epsilon” 
multiplicity of reflections is … negligible?

Sorry for chucking pragmatism into a dogmatic debate 😀

Cheerio Graeme


########################################################################

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB 
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.jiscmail.ac.uk_cgi-2Dbin_WA-2DJISC.exe-3FSUBED1-3DCCP4BB-26A-3D1&d=DwQFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=aGhwDJW1Tz5Uv5JNfNgM0GK130Iyy3LfbUxrB8T_uo0&e=>
 &A=1

This message was issued to members of www.jiscmail.ac.uk/CCP4BB 
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.jiscmail.ac.uk_CCP4BB&d=DwQFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=XxFj75JTvy4wp52qIe1FqQsa7--uLknEz4dPWcvffP0&e=>
 , a mailing list hosted by www.jiscmail.ac.uk 
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.jiscmail.ac.uk&d=DwQFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=9E0X2NSQ08FgQv_wzJVxbzs5lsC4iLM9PlOGHnQhw6Y&e=>
 , terms & conditions are available at 
https://www.jiscmail.ac.uk/policyandsecurity/ 
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.jiscmail.ac.uk_policyandsecurity_&d=DwQFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=tQo38qgGTFaUn_RZb-ZF04Kjn2Gh2oJr1aNHHE-ELRw&e=>
 

 

  _____  

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB 
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.jiscmail.ac.uk_cgi-2Dbin_WA-2DJISC.exe-3FSUBED1-3DCCP4BB-26A-3D1&d=DwMFaQ&c=Dbf9zoswcQ-CRvvI7VX5j3HvibIuT3ZiarcKl5qtMPo&r=HK-CY_tL8CLLA93vdywyu3qI70R4H8oHzZyRHMQu1AQ&m=vb2CFOGKla49hE2sbHAt6LCUz63K7uis9PmSUxUgMcM&s=aGhwDJW1Tz5Uv5JNfNgM0GK130Iyy3LfbUxrB8T_uo0&e=>
 &A=1 

 

  _____  

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB 
<https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1> &A=1 


########################################################################

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1

This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list 
hosted by www.jiscmail.ac.uk, terms & conditions are available at 
https://www.jiscmail.ac.uk/policyandsecurity/

Reply via email to