Top panel: The distribution of projected local galaxy surface density in the low‐﹩L_{\mathrm{X}\,}﹩ (solid line) and high‐﹩L_{\mathrm{X}\,}﹩ (dotted line) samples. Bottom panel: The fraction of galaxies with ﹩B/ T< 0.4﹩ as a function of projected local galaxy density. The values are corrected for background contamination as described in the text. The field fraction (which corresponds to ﹩\Sigma _{\mathrm{local}\,}\sim 0﹩) is shown as the star at an arbitrary density for display purposes. The circles and triangles correspond to the low‐﹩L_{\mathrm{X}\,}﹩ and high‐﹩L_{\mathrm{X}\,}﹩ samples, respectively. Bin sizes are adaptively varied so that each includes 75 galaxies; the horizontal error bar shows the bin span, and the point represents the median. Vertical error bars are determined from bootstrap resampling that accounts for the uncertainty in the background correction.