For the GBM sample, PR_max versus FWHM_min. Blue dots represent Type-I GRBs (i.e. SGRBs and SEE-GRBs), while red dots represent Type-II GRBs. Lighter dots correspond to individual GRB data, and darker dots indicate the geometric mean of data from GRB groups sorted by increasing FWHM_min. Each Type-I group consists of 50 GRBs; each Type-II group consists of 270 GRBs. Dotted lines show the best fit for Type-II GRBs. Shaded areas illustrate ten regions with a detection efficiency ranging from 0 to 1. Cyan dashed lines indicate the 50% and 90% detection efficiency contours.