Robustness of the reconstructed luminosity function and cumulative formation-rate evolution for the non-ML GRB catalog to the uncertainty in the luminosity evolution parameter k. Curves are shown for the best-fit value of k and for the two values corresponding to the 1σ EP range, defined by τ = ±1. The luminosity functions and cumulative formation rates retain nearly the same shape across the allowed range of k, differing primarily in normalization.