Comparison of our model metallicity distribution function (MDF) with recent observations. The red histograms shows data from Adibekyan et al. (2012) (left), Bovy et al. (2012a) (middle), and Brauer et al. (2013) (right). In each panel the black and blue curves plot the model data with no error in [Fe/H] and convolved error of δ[Fe/H] = 0.2 dex, respectively. We have selected a very local sample to compare with the high-resolution nearby sample by Adibekyan et al. (2012) (as indicated) and a range in z and r to approximately match the SEGUE data studied by the other two works. A shift in the peak from [Fe/H] ~ 0 to [Fe/H] ~ − 0.3 dex for both observed and simulated data is seen when considering a higher sample depth.