Δ(R_e − M_∗) as a function of the redshift for GRB host galaxies. The orange and red circles are GRB hosts at z ≲ 1 from Kelly et al. (2014) and Blanchard et al. (2016), respectively. The blue circles are the GRB hosts considered in this study. Dark GRBs are highlighted by a thick black circle. The gray squares are the median of the Δ(R_e − M_∗) for each redshift bin. The associated error bars are the standard deviation using the MAD estimator. The black line at y = 0 represents the expected median values for a GRB hosts population that do not suffer from environment bias.