in catalysis
For the process: \[k = A\ \text{e}^{\frac{-E}{R\ T}}\] 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.
PAC, 1976, 46, 71. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units - Appendix II. Definitions, Terminology and Symbols in Colloid and Surface Chemistry. Part II: Heterogeneous Catalysis' on page 82 (