For the process: \[k = A\ \rm{e}^{\frac{-E}{R\ T}}\] where \(k\) is a rate constant, \(A\) the frequency factor and \(E\) the activation energy, \(A\) and \(E\) sometimes exhibit compensation, i.e. they change in the same direction with change in catalyst for a given reaction or with change in reaction for a given catalyst.