Abstract: An advanced correction method is provided. A target layout pattern is provided, and is corrected by a correction model to obtain a corrected pattern. A simulation is performed on the corrected pattern to obtain a simulation contour. A plurality of off-target evaluation points are established on the simulation contour, the simulation contour is compared with a target layout pattern, and a plurality of risk weighting values of each of the off-target evaluation points are obtained. A risk sum value obtained by summing up the risk weighting values of each of the off-target evaluation points is sorted into a processing sequence in descending manner. The target layout pattern is identified, classified and grouped into a plurality of pattern blocks. The corrected pattern is modified according to the processing sequence, so as to converge the simulation contour of the corrected pattern being modified to be close to the target layout pattern.