Simulations used to estimate the completeness in the selection of pBzK galaxies. Upper panel: position of the sources used to estimate the incompleteness in the two fields, taken as real pBzK galaxies at K< 22. Central panels: example of the density of simulated sources in the BzK plane, when sources are scaled to K = 22 (left) and K = 23.7 (right), and when the effect of noise is included (see text for details). The case of GOODS-S is shown in this example. Lower panel: big dots delineate the completeness (i.e., the fraction of objects originally located in the pBzK region that are recovered even when the appropriate photometric noise is included) as a function of the K-band magnitude resulting from the full simulations, separately for the two fields. The small dots show the contamination, i.e., the fraction of objects detected in the pBzK region that were originally located outside the same region.