15. The computer system of claim 12 , wherein the characteristics are selected among signals comprising: user location; user device information; publisher; local query time; local time of page request; page identity; content item properties; keyword in page request; keyvalue page visiting history; content item interaction history; and combinations thereof.
15. The computer system of claim 12 , wherein the characteristics are selected among signals comprising: user location; user device information; publisher; local query time; local time of page request; page identity; content item properties; keyword in page request; keyvalue page visiting history; content item interaction history; and combinations thereof. 17. The computer system of claim 15 , further comprising ranking at least some of the characteristics with regard to the interaction proneness, wherein the ranking is taken into account in distributing the content item.