is applied to take into account the effect of the filtering of the data on the photometric measurements of faint, non-masked sources [@Popesso2012]. At 250$\mu$m, 350$\mu$m, and 500$\mu$m, the photometric uncertainties are not dominated by instrumental noise but by the confusion noise caused by neighboring sources [@Dole2003; @Nguyen2010]. We thus measured the mean flux of the sources computing the mean flux in the pixels centered on a stacked source following @Bethermin2012b. This method minimizes the uncertainties and a potential contamination caused by the clustering of galaxies [@Bethermin2010b]. Finally, we used the same method, but on the beam-convolved map, for LABOCA and AzTEC data as they are noise limited and lower uncertainties are obtained after this beam smoothing. LABOCA and AzTEC maps do not cover the whole area. We thus only stack sources in the covered region to compute the mean flux densities of our various sub-samples. The source selection criteria being exactly the same inside and outside the covered area, this should not introduce any bias.\
These stacking methods can be biased if the stacked sources are strongly clustered or very faint. This bias is caused by the greater probability of finding a source close to another one in the 