PS on a matter of terminology, what you are calling the 'sd' (i.e.
'standard deviation') is not the true standard deviation, it's only an
estimate since it's obtained from the data. Such an estimate of the
standard deviation used to be called (you guessed it!) the 'estimated
standard deviation' (o
Bryan,
Assuming that your values of sd(I) are accurate estimates of the
standard uncertainties of your Is, then I/sd(I) is a normalised
variate with SU = 1. So the SU of the mean value of I/sd(I) (where as
Phil says the Is are simply the measurements of the various
reflections in a shell) is give
I don't think this is a meaningful question. For Mn(I/sd), we take all
measurements of each reflection h to get its average Ih, and an estimate of the
SD of this average sd(Ih) (from the adjusted input sigmas), hence the ratio
Ih/sd(Ih). Then we average this ratio over all reflections in a resol
[ scala 3.3.16 ]
in scala's "final table", there's "Mean((I)/sd(I))". i could be wrong,
but the error of this measurement seems to me to exist, considering
the uncertainty of sigma = 1 / sqrt( 2 (N-1) ) ... but its not clear
where the logfile has the values of I or sigma and N that correspond
to
