selecting content for and distributing content to users based on {HEAD ~ their association} with {TAIL ~ the affinity group} 
with
selecting content for and distributing content to users based on { HEAD ~ their association } with { TAIL ~ the affinity group }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL