Figure 2. Delivery Mode (Cesarean Section vs. Vaginal Delivery): PS Kernel Density Estimates and Common Support.
The solid (C-section) and dotted (vaginal birth) curves indicate the within-group smoothed histograms for the PSs, based on kernel density estimates. The grey horizontal line indicates a reference at 5 observations. The vertical lines indicate the common support, which we define as the interval on which the within-group kernel density estimates are mostly 5 or above. Here the observed common support is (0.095, 0.530).