Kaplan-Meier estimators of the XLF of the YSOs in V1818 Ori calculated for three distances: 900 pc (orange), 400 pc (red), and 270 pc (black). The curves at the 95% confidence range are plotted as dashed lines. The XLF of the YSOs associated with κ Ori (Pillitteri et al. 2016) is shown for comparison. The arrows mark the medians of the different XLFs. The best agreement to the XLF of the κ Ori group (distance 250–280 pc) is obtained for a distance of 270 pc.