Visualization of the correlation between M_h and a_h in Model I: The single parameter 90%-confidence region defined by Δχ² ≤ 2.71 and corresponding to a 74%-joint-confidence region is black-rimmed and shaded in dark gray, while the 3σ region (Δχ² ≤ 9, 99%-joint-confidence region) is the total black-rimmed, gray-shaded area. The cross marks the location of the best fit. The four curves define the loci of constant halo mass inside a sphere of radius 14.1 kpc (red dashed), 50 kpc (blue dotted), 100 kpc (blue dashed-dotted), and 200 kpc (blue dashed-dotted-dotted).