The halo bias b(M,x) as a function of σ(M), at distance x = 50   h^-1Mpc and redshift z = 0. We show our results for halos defined by a density threshold δ_∗ = 400 (left panel), δ_∗ = 800 (middle panel), and δ_∗ = 1600 (right panel). The solid line is our model (36), with α = 2.2 as for the mass functions of Fig. 3. The dashed line is the fit from Sheth et al. (2001), for halos with δ_∗ = 200, which is the same in all panels and in Fig. 1. The points are the results from numerical simulations of Tinker et al. (2010).