  In this work we present a general method, commonly applied to the numerical
analysis of stochastic models, to interpolate AC-DC differences (usually
denoted by the greek letter $\delta$) between calibration points in thermal
transfer standards. This method assigns a power-law behaviour to AC-DC
differences, solely under the assumption that $\delta$ must be some
smooth-varying function of voltage and frequency. We argue it may be
straightfowardly applied to all working ranges of the standards, with no
distinction.
