Histograms of extinction-corrected rest-frame U−V color for AGN hosts (solid magenta lines) and parent galaxies (gray filled histogram) in two ranges of stellar mass, 10 < log M_⊙ < 10.6 and log M_⊙ > 10.6, respectively. The peak value of each histogram has been rescaled to unity. Red and blue lines are the Gaussian fitting results for red sequence and blue cloud, and the solid green lines mark the residual distribution after subtracting the sum of the two Gaussians. The vertical dashed lines indicate the boundaries of the green valley, where the residual distribution surpass the Gaussian fit for blue (blue-side) or red (red-side) galaxies.