17. The apparatus of claim 13 , wherein in generating the optimized list the processor circuit is configured, until all elements have been sorted, for: a) computing for each element of the elements list, an added singleton coverage increase so that the higher number of singleton the element contains, the higher the coverage increase, b) regardless of the elements score, placing the element with the highest coverage at a bottom of a sorted list, c) repeating steps a) and b) until singleton coverage cannot be increased anymore, d) removing ordered elements from the elements list, and e) repeating step a) until the elements list is fully depleted.
18. The apparatus of claim 17 , wherein in the placing step, if several elements have the same coverage increase, the processor circuit is configured for placing the element with highest total popularity score at the bottom of the sorted list.