Average apparent jet structure. The two larger panels show the constraints on the SGRB average apparent structure obtained from our analysis: solid lines show the medians of the projected posterior distributions of the jet structure functions at fixed θ_v from the full sample analysis (red: ; blue: ), while dashed lines refer to the flux-limited sample (orange: ; cyan: ). The shaded region around each line encompasses the corresponding 90% credible range at each fixed θ_v. Dotted lines show reference power law trends. The light green contours show the 50% and 90% credible regions of (L, θ_v) (middle panel) and (E_p, θ_v) (bottom panel) for GRB 170817A (Sect. 2.4.3). The insets show the posterior distributions on the parameters A and σ_c that determine the dispersion around the average structure within the population. The top smaller panel shows the posterior distributions on the logarithms of the transition angles, ln(θ_c) (grey) and ln(θ_w) (green), with the results for the full sample shown as filled areas, and those for the flux-limited sample shown as dashed lines.