Left panel: contamination versus incompleteness for groups with at least ten members. Point size is proportional to the number of true members in a group. Majority of the large groups and clusters are located in the bottom left corner with low contamination and incompleteness. This figure should be compared with results presented in Wojtak et al. (2018). Right panel: cumulative distribution of contamination and incompleteness for groups shown in the left panel. For about 20 percent of the groups the contamination (red line) or incompleteness (blue line) is exactly zero.