Metabolomics Society Forum

Software => MS-DIAL => Topic started by: Bernadette on November 30, 2021, 04:47:41 AM

Title: S/N ratio
Post by: Bernadette on November 30, 2021, 04:47:41 AM
Dear all,

I am working with GC-TOFMS data and have some questions regarding the S/N ratio.
I have exported two files from the Alignment result:
(1)   exported Raw data matrix (Area)
(2)   S/N matrix
In (1) I have the column S/N average for each Alignment ID. But when I look at the S/N ratios in (2) and calculate the average for each Alignment ID there, I get different values.
When I look then at the Peak list for a specific sample, I see different S/N ratios compared to the (2) S/N matrix.
So, I am wondering, how the S/N ratio is calculated in MSDial? It is also hard to evaluate the noise, because when you look in the alignment spot viewer at the chromatogram, you only see the zoomed peak and not the baseline. 

It would be very helpful, if someone can explain this.

Best regards,
Bernadette