Variation of the obscured fraction (A₂/(A₁ + A₂)) with source intrinsic X-ray luminosity (solid line) for L07 (left), S05 (middle left), KI (middle right), and KIM (right). The top row considers sources with reliable photometry in the K_s + IRAC bands, while the bottom row considers sources with reliable photometry in the K_s + IRAC + MIPS₂₄ bands. The CDFS and COSMOS samples are considered together. The shaded and hatched regions show the associated statistical uncertainty. The dotted line refers to the obscured fraction observed in the whole sample (Fig. 4). A moving bin is used as described in Fig. 1.