Comparison of polarisation-related parameters for alternative models. The lower frames show kernel-density-estimated parameter correlations and the diagonal frames the histograms of individual parameters. The correlation coefficients are listed in the remaining frames. The background images and histograms drawn with black lines correspond to the default model D with all clumps d < 300 pc. The data for the alternative models H (internal heating sources) and M₅ (modified dust properties) are drawn in red and blue, respectively.