Transparent ruler – like in the good ol’ days [Bioanalytics]
Hi Ohlbe and Hötzi,
Thanks for your qualified opinions.
I am inclined to do this:
where the red line indicates the level of noise (in this case, right of the peak) and the greeen one is the signal. Roughly.
Note that in both cases I quantify s as well as n in one direction from the baseline mean or median or whatever.
Thus I am landing at s:n = (18-4.1) / (8-4.1) = 3.6.
I am not in any way claiming this is better or worse, only that this is my idea of an approach.
If I recall correctly, if you are "a large software vendor" -and I will mention none in particular- you can also do something like:
which gives a result of about 5.
Personally, I would of course always adjust k so that s:n is not less than 10 or so, just to avoid questions. I mean, I care about my data because I am not a nasty person


Thanks for your qualified opinions.
I am inclined to do this:
lines(c(5.6, 5.6), c(4.1,18), col="green", lwd=6)
lines(c(8, 8), c(4.1,8.8 ), col="red", lwd=6)
where the red line indicates the level of noise (in this case, right of the peak) and the greeen one is the signal. Roughly.
Note that in both cases I quantify s as well as n in one direction from the baseline mean or median or whatever.
Thus I am landing at s:n = (18-4.1) / (8-4.1) = 3.6.
I am not in any way claiming this is better or worse, only that this is my idea of an approach.
If I recall correctly, if you are "a large software vendor" -and I will mention none in particular- you can also do something like:
k=3 #a miserable sad pointless constant to make s:n look better ??
a=sd (y3[400:714]) #sd of points on the peak
b=sd (y3[800:1000]) #sd of points adjacent to the peak
sn=k*a/b
which gives a result of about 5.

Personally, I would of course always adjust k so that s:n is not less than 10 or so, just to avoid questions. I mean, I care about my data because I am not a nasty person



—
Pass or fail!
ElMaestro
Pass or fail!
ElMaestro
Complete thread:
- Isn't it time for an open source chromatographic format ElMaestro 2018-11-04 21:54 [Bioanalytics]
- Isn't it time for an open source chromatographic format nobody 2018-11-05 09:00
- and now that we are at it ElMaestro 2018-11-05 13:53
- and now that we are at it nobody 2018-11-05 16:33
- and now that we are at it ElMaestro 2018-11-05 18:19
- Transparent ruler – like in the good ol’ days Helmut 2018-11-05 20:39
- Transparent ruler – like in the good ol’ days Ohlbe 2018-11-05 22:14
- Transparent ruler – like in the good ol’ daysElMaestro 2018-11-05 22:43
- Slow down, you move too fast […] Feelin’ Groovy Helmut 2018-11-06 02:05
- Slow down, you move too fast […] Feelin’ Groovy nobody 2018-11-06 09:29
- Yes it went a little fast ElMaestro 2018-11-06 11:09
- Yes it went a little fast nobody 2018-11-06 12:05
- Yes it went a little fast ElMaestro 2018-11-06 12:10
- Yes it went a little fast Helmut 2018-11-07 16:09
- Yes it went a little fast ElMaestro 2018-11-07 16:22
- Yes it went a little fast nobody 2018-11-07 18:30
- Purpose of S:N? Helmut 2018-11-08 09:46
- Purpose of S:N? ElMaestro 2018-11-08 22:27
- Purpose of S:N? nobody 2018-11-09 10:06
- Purpose of S:N? Helmut 2018-11-09 11:34
- Purpose of S:N? nobody 2018-11-09 12:08
- Purpose of S:N? Helmut 2018-11-09 12:34
- Purpose of S:N? nobody 2018-11-09 12:08
- Purpose of S:N? Helmut 2018-11-09 11:34
- Purpose of S:N? Helmut 2018-11-09 11:26
- Purpose of S:N? ElMaestro 2018-11-09 13:16
- Purpose of S:N? nobody 2018-11-09 10:06
- Purpose of S:N? ElMaestro 2018-11-08 22:27
- Yes it went a little fast ElMaestro 2018-11-07 16:22
- Yes it went a little fast Helmut 2018-11-07 16:09
- Yes it went a little fast ElMaestro 2018-11-06 12:10
- Yes it went a little fast nobody 2018-11-06 12:05
- Yes it went a little fast ElMaestro 2018-11-06 11:09
- Slow down, you move too fast […] Feelin’ Groovy nobody 2018-11-06 09:29
- Slow down, you move too fast […] Feelin’ Groovy Helmut 2018-11-06 02:05
- Transparent ruler – like in the good ol’ daysElMaestro 2018-11-05 22:43
- Transparent ruler – like in the good ol’ days Ohlbe 2018-11-05 22:14
- and now that we are at it nobody 2018-11-05 16:33
- and now that we are at it ElMaestro 2018-11-05 13:53
- Isn't it time for an open source chromatographic format paulhurleyuk 2018-11-05 16:27
- Isn't it time for an open source chromatographic format nobody 2018-11-05 09:00