A process simulation database includes process simulation data of a plurality of process simulations based on a different variation of a plurality of process parameters. For each process parameter, for an initial number of different process parameter values, process simulation data of a process simulation are included in the process simulation database. A process parameter classifier calculates a linearity indicator for a varied process parameter based on an analysis of the process simulation database with respect to a linearity of an influence of a variation of at least the varied process parameter on the process simulation data in the process simulation database. Further, a process simulation data processor changes the initial number of different process parameter values of the varied process parameter, for which process simulation data of a process simulation are included in the process simulation database, based on the calculated linearity indicator, to obtain a processed process simulation database.