I just started learning about Bland-Altman plots. So my data consists of angles from a particular device and another set of angles from another device. The angles on both devices vary between -5 degrees to 20 degrees. So I did my bland-Altman plot and the diagram looks fine.
However, I am wondering whether I should be considering the absolute value of the angles instead of both negative and positive values.
So should I be using the absolute value for the calculations?