Illustration of the probability of a negative bias. We show the applied bias correction (mean of 100 realizations) as a function of P3/P0_c. The colors indicate the different counts within r₅₀₀: 1000 (red crosses) and 30 000 (black circles). A negative bias correction is only needed for very structured clusters and even then it is only on the order of 1%. The solid and dotted lines show the different morphological ranges as discussed below in Sect. 5.