What comes first? Social strength or common friends?

[Abstract of]: NetMob, 5-7 April 2017, Milan, ItalySocial networks are made out of strong andweak links having very different structural anddynamical properties. Social scientists have longrecognized the value of weak links in information discovery but also their relative structuralweakness that makes them more likely to decayin the future. What what features of humaninteraction build a strong tie? Here we approachthis question from an practical way by findingwhat are the properties of social interactions thatmake ties more persistent and thus stronger tomaintain social interactions in the future. Usinga large longitudinal mobile phone database webuild a predictive model of tie persistence basedon intensity, structural and temporal patternsof social interaction. While our results confirmthat structural (embeddedness) and intensity(number of calls) are correlated with tie persistence, we find that daily temporal featuresof communication events in a tie are betterand more efficient predictors for tie persistence.Specifically, although communication betweenlinks is always bursty we find that links that aremore bursty than the average are more likely todecay, signaling that the strength of the tie isnot only reflected in the intensity or topology ofthe network, but also on how we distribute intime our interactions with our relationships. Ourresults not only are important to understandthe strength of social relationships but also tounveil the entanglement between the differenttemporal scales in networks, from microscopictie burstiness to network evolution