Top: cumulative distribution in the apparent I_AB magnitude of the total MASSIV sample (green line), the close pair sample (red line) and the total MASSIV sample with I_AB ≤ 23.9 (blue line). Middle: the same than before, but the red line shows the distribution of the major merger sample. Bottom: Kolmogorov-Smirnov estimator D of the total MASSIV sample distribution against the close pair (blue solid line) and the major merger (red dashed line) distributions. We computed D for those galaxies brighter than a given I_AB magnitude. The solid (dashed) horizontal line marks the minimum in the D distribution for close pairs (major mergers). The vertical solid line marks the I_AB magnitude at the minimum value of D, I_AB,comp = 23.9.