Compare two datasets of different units

So I have two datasets

Set 1 contains values stored as 575x1 double, in the unit of kBq/cc, it is measured each half second

Set 2 contains values stored as 487x1 double, in the unit if Bq, it is stored each whole second

I want to plot them in the same figure to compare the two sets, but due to there being a order shift, the second set of data is much larger than the first set.

How can I find a calibration factor/coefficient that maybe I can use to make the second set in the same units as the first set (i.e make Bq to kBq/cc)?

I was thinking about a regression analysis, but I do not really know if the R I get from set 1 acutally is just to multiply with set 2 and it gives the right unit. I am really out on deep water and unsure of what to do.

I will post the three plots I've made so it will be easier to visualize the data

Answer 1

[Veronica Taurino]

You could just plot them in one figure with two axes:

Create Chart with Two y-Axes - MATLAB & Simulink - MathWorks Italia

[Amanda Eriksson]

No, I could. But I need to convert the Bq set to kBq/cc so that I can compare two sampling instruments, and it will be easier if they would be of the same unit

[Veronica Taurino]

I am not sure about what you mean, I never studied Radioactivity. kBq/cc is 1000 Bq/cc, kind of density, while Bq is the SI derived unit. I thought you can't really make Bq in kBq/cc unless you get a reference 'volume' to evaluate it... sorry, I can't help

[Amanda Eriksson]

Yes, I am comparing two blood sampling devices (they detect the true coincidences that happens when radioactivity decays, within the drawn blood). But instrument 1 is calibrated so that we get the measurement in kBq/cc, while for instrument 2 it only give out in Bq, thus we need a calibrationfactor. Usually when performing this onto patients, we take the catheter and measures it in a well counter. But this measurement above is simply done with saline and a radiotracer FDG, so the catheter wasn't measured in a well counter.

And I thought that maybe in someway it would be possible to find a calibrationfactor between the two by comparing them, but maybe that isn't possible. Very unsure, but thank you!

[Veronica Taurino]

I get it better know. Maybe you already know it but try checking with the instrument producer, they should provide some calibration factors.