Hi everyone,
I was looking at the NOE tool in relax and was quite surprised by the
way errors are calculated...
In the file 'specific_fns/noe.py' of the 1.2 line (r3354), the function
for the noe error is :
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\/ {sd(sat)*I(unsat)}^2 + {sd(unsat)*I(sat)}^2
sd(NOE) = -----------------------------------------------
I(unsat)^2
Shouldn't this be more like :
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sd(NOE) = NOE * \/ {sd(sat)*I(sat)}^2 + {sd(unsat)*I(unsat)}^2
In other words, shouldn't the NOE error be the product of the NOE by the
root of the squared sum of relative errors for Isat and Iunsat,
respectively ? Ain't this the way one should normally propagate errors
for value calculated by a division (like NOE=Isat/Iunsat)
What are the main advantages of calculating errors with either
techniques and why the one is relax should be more accurate ?
Thanks !
Sébastien
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|| Sebastien Morin ||
||| Etudiant au PhD en biochimie |||
|||| Laboratoire de resonance magnetique nucleaire ||||
||||| Dr Stephane Gagne |||||
|||| CREFSIP (Universite Laval, Quebec, CANADA) ||||
||| 1-418-656-2131 #4530 |||
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NOE errors