We discuss adaptive strategies for choosing regularization parameters in TikhonovPhillips regularization of discretized linear operator equations. Two rules turn out to be entirely based on the underlying regularization scheme. Among them only the discrepancy principle allows to search for the optimal regularization parameter from the easiest problem. This possible advantage cannot be used with the standard projection scheme. We present a modified scheme, in which the discretization level varies with the successive regularization parameters, and which allows to use the advantage, mentioned before. Key words: discrepancy principle, projection method, general source condition
Peter Mathé, Sergei V. Pereverzev