A note on fitting multiexponential functions of time to experimental data

Abstract

A method based on the theory of difference equations, which was described recently for fitting multiexponential functions of time to experimental data, is shown to be unsuitable for experimental data with inherent error variation. While it is substantially correct in theory and works with exact values of such functions, the criterion given in the method for determining the number of exponentials for data with inherent error is incorrect and the number of exponentials cannot be so determined. Even when the number of exponentials is assumed correctly, the method will not work for points lying on a known function when the values of these points have been rounded to a relative accuracy greater than could be expected for data from most biological experiments.