I’m going to post this here even though this question straddles Chemistry and Physics. I think I know the answer but I’d like confirmation. Let's say I am measuring a property P that is decaying exponentially, but I am measuring it using two different test methods. Let’s call them method A and method B. The data from method A fit the curve: P(t) = A0e-αt The data from method B fit the curve: P(t) = B0e-βt In this case, I know the methods well enough that I know that A0 and B0 will be different numbers. But isn’t it true that α = β?