Okay, I think I understand:
<I> is the weighted average of the equivalent scaled intensities, with
1/sigma^2 as weight for each reflection.
Is there a derivation/rationale for using 1/sigma^2 as the weight? I see
that this would give more credence to better I/sigma measurements, but I do
not yet understand why this is exactly the correct weight. Why not simply
1/sigma, or 1/sigma^87?
I apologize for the basic nature of this inquiry, but I would like to
understand all of this fully. And...you can always ignore!
Jacob
*******************************************
Jacob Pearson Keller
Northwestern University
Medical Scientist Training Program
Dallos Laboratory
F. Searle 1-240
2240 Campus Drive
Evanston IL 60208
lab: 847.491.2438
cel: 773.608.9185
email: [email protected]
*******************************************
----- Original Message -----
From: "Jim Pflugrath" <[email protected]>
To: <[email protected]>
Sent: Thursday, March 18, 2010 10:12 AM
Subject: Re: [ccp4bb] Equation for combining measurements
The weighted mean is used. Wikipedia
http://en.wikipedia.org/wiki/Weighted_mean has the equation(s).
-----Original Message-----
From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of
Eleanor Dodson
Sent: Thursday, March 18, 2010 4:59 AM
To: [email protected]
Subject: Re: [ccp4bb] Equation for combining measurements
Isnt it in the scala documentation?
Eleanor
Jacob Keller wrote:
Dear Crystallographers,
A basic question: what is the equation currently used to combine/merge
multiple measurements of I and sigI? (Or a reference would be fine as
well (or maybe better.))
Thanks,
Jacob Keller
*******************************************
Jacob Pearson Keller
Northwestern University
Medical Scientist Training Program
Dallos Laboratory
F. Searle 1-240
2240 Campus Drive
Evanston IL 60208
lab: 847.491.2438
cel: 773.608.9185
email: [email protected]
*******************************************
