I would like to know when I can determine that a system is stable. I've seen Stability of a system but this is very theoretically. My background is that I've set up a measurement system to detect the signal changes of a gas sensor. Means, when I add such and that of a gas the sensor will change accordingly.
But when do I state that the signal I observe is stable? Per eyeballing it isn't that hard but I would like to use a better, more reproducible characteristic. A common thumb of rule is fine.