The server determines an interaction score for {HEAD ~ each} of {TAIL ~ the interactions}, wherein each interaction score is based on a type of the respective one to one interaction and an age of the respective one to one interaction 
The server determines an interaction score for { HEAD ~ each } of { TAIL ~ the interactions } , wherein each interaction score is based on a type of the respective one to one interaction and an age of the respective one to one interaction
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH