coefficient of variation May 13, 2020, 05:21:48 AM Hi Hiroshi,regarding the coefficient of variation (CV%) shown by the MS-DIAL normalization report. I have been manually calculating the QCs across samples and QCs, for some internal standards, but I do not manage to reproduce exactly the same values. in MS-DIAL, are the CV% calculated based on the log transformed values? (as the report shows the log scale)I tried both with and without log transforming. When I use the log values, I use the following formula: = SQRT (10^(LN(10)*STDEV^2)-1)as discussed here: 10.15406/mojpb.2017.06.00200I attach the CV% calculated on the log values (for QCs and Samples), and the corresponding ones from MS-DIAL (in red)(Note: they are not expressed as %, but as fraction, i.e. CV 0.15 = 15%)Thank you!Stefano

Re: coefficient of variation Reply #1 – May 13, 2020, 07:43:25 PM Thanks Stefano,the CV value is simply calculated by the original, i.e. non-transformed values although the Y-scale is finally visualized by log-transformed value. I will prepare both CV values into the figure at next update.Thanks,Hiroshi