The use of prior information for extracting the post-edge background

A new method for extracting the post-edge background mu0 is proposed, the method of Bayesian smoothing. A further evolution of the smoothing spline method is considered as well. Both techniques are capable to take into account prior information about the peculiarities on the mu0. In addition, since the Bayesian approach works in terms of the posterior probability density functions, it contains a natural way to determine the errors of the mu0 construction, which has always been an unresolvable problem for any other method. Even with use of the prior information, which narrows the posterior probabilities, the errors of mu0 are shown to be larger than the experimental noise.