Fractional deviation from GR (Δσ_∥ = σ_{∥ ,MG}/σ_{∥ ,GR}−1) for the four symmetron models (colored lines) for separations r = 1 (solid lines) and 5 h^-1 Mpc (dashed) as a function of ambient density, δ. Deviations without binning in δ are shown as solid (r = 1 h^-1 Mpc) and dashed (r = 5 h^-1 Mpc) horizontal gray lines. Yellow points are the ratio of the mean halo mass to the rescaling mass (right axis; see Sect. 2), with the bars denoting the standard deviation within the bin, and the orange shading representing the band of partial screening found in Gronke et al. (2015b).