Masssegregation ratio, Λ_MSR, as a functionof the numbers of clumps, N_MST, in the NGC 2264 cloud (panel a) and in its three subregions (panel b). Error bars represent the ± 2σ uncertainties. Values above Λ_MSR ≃ 1 (black solid line) suggest mass segregation. Completeness levels are indicated with vertical dashed lines. Panel a: median segregation ratio for the 15 most massive clumps of NGC 2264, calculated over N_MST= 4 to 15, is (red segment). Panel b: the Λ_MSR function of clumps in the central subregion (black symbols) is three to two times higher than that in the northern and southern subregions (in red and blue, respectively) over the range of N_MST= 4−33.