. ▁ ▁The ▁Open So cial ▁initi ative ▁a ims ▁to ▁bridge ▁the ▁member ▁overlap ▁between ▁various ▁online ▁social ▁network ▁services . ▁ ▁Social ▁network ▁aggreg ators ▁such ▁as ▁Friend Feed ▁represent ▁conne x ion ▁between ▁people ▁throughout ▁directed ▁graphs . ▁They ▁adopt ▁a ▁following ▁approach , ▁rather ▁than ▁a ▁fri ending ▁one , ▁where ▁“ A ▁follows ▁B ” ▁does ▁not ▁imply ▁“ B ▁follows ▁A ”. ▁Each ▁account ▁is ▁then ▁represented ▁by ▁a ▁node ▁whereas ▁the ▁following ▁relationship ▁is ▁represented ▁by ▁an ▁edge . ▁The ▁relationships ▁between ▁these ▁nodes ▁appear ▁to ▁be ▁linked ▁to ▁their ▁age ▁and ▁their ▁sphere ▁of ▁influence . ▁Indeed , ▁the ▁nodes ▁which ▁have ▁joined ▁the ▁network ▁most ▁recently ▁get ▁less ▁influence ▁than ▁older ▁ones . ▁Therefore , ▁on ▁social ▁network ▁aggreg ators , ▁new ▁nodes ▁tend ▁to ▁connect ▁to ▁nodes ▁with ▁high ▁degrees . ▁ ▁First ▁social ▁network ▁aggreg ators ▁Histor ically , ▁social ▁media ▁aggreg ators ▁have ▁always ▁existed . ▁Indeed , ▁newsp apers ▁act ▁in ▁that ▁way : ▁journal ists ▁summar ize ▁numerous ▁pieces ▁of ▁information ▁and ▁try ▁to ▁bring ▁relevant ▁content ▁from ▁many ▁sources , ▁in ▁a ▁synth es ized ▁and ▁understand able ▁way . ▁The ▁purpose ▁is ▁to ▁provide ▁under stable ▁information ▁for ▁everyone ▁about ▁more ▁or ▁less ▁complex ▁topics ▁so ▁that ▁people ▁will ▁not ▁have ▁to ▁spend ▁hours ▁finding ▁and ▁analyz ing ▁news ▁from ▁all ▁around ▁the ▁world . ▁Moreover , ▁it ▁was ▁also ▁an ▁aggreg ator ▁for ▁job ▁offers ▁and ▁other ▁type ▁of ▁ad s . ▁ ▁Collect ing ▁data