A multilevel path analysis of social network dynamics and the mutual interdependencies between face-to-face and ICT modes of social interaction in the context of life-cycle events

The interaction between the use of Information and Communication Technology (ICT) and travel and transportation has been an important issue in transportation research. ICT may substitute work trips and enhances non-work travel. Particularly for social activity and travel behaviour existing studies suggest that ICT has complementary effects: ICT enhances social travel or increases efficiency in scheduling the activity by introducing flexibility into it or does both. However, with changing life events social network and associated travel may change for each ego-alter combination. These disaggregated effects ultimately bring in changes to the overall travel schedule of the ego and eventually to the local travel demand. The paper takes these dynamic effects into consideration and argues on the interrelationships between the modes of social communication. The study shows that causal interferences between face-to-face and ICT modes of communication can be in either direction. It is not necessarily from ICT to face-to-face as was assumed in the contemporary researches in the field. Using the event based retrospective data collected in 2011 in the Netherlands a multilevel Structural Equation model of social interaction frequency is estimated. Results show that dynamics of a social network influences dynamics of social interaction. The study confirms the hypothesis that the modes of social interaction (face-to-face and ICT) have a mutual causal relationship. They substitute and complement each other. Considering network dynamics induced by life-cycle events, face-to-face interaction substitutes ICT interaction and ICT interaction complements face-to-face communication.