The first row of Table 5 confirms that the hubs found in the neighbourhoods of ridgemapped query terms are items that tend to be closer to the search space mean vector, and that this effect is radically reduced with max-margin estimation.
the second row of the table shows another factor at play, that has a major role in the cross-modal setting, and it is only partially addressed by max-margin estimation: Namely, in vision-to-language mapping, there is a strong tendency for hubs (that, recall, have an important effect on performance, as they enter many nearest neighbour lists) to be close to a training data point.