Distribution of contrast value changes in CPD : Star and Gap : CPD with respect to the change in a single model parameter using boxplots. Each median is highlighted by a red line, the middle 50% of data are represented by a box, and the maximum whisker length equals ∆w = 1.5 IQR. The labels to the left characterize the data used in generating the corresponding boxplots to the right of the label. A label refers to a shared parameter value. The label above any column refers to a parameter that has been increased to its next simulated value. Outliers are shown as black diamonds. For details, see Sect. 3.7.