- Published on 24 June 2015
'Big Data' from electronic records derived from mobile telephone calls enables the study human behaviour and sociality in a quantitative way and with unprecedented statistical power. Cell phones are ubiquitous and Call Detail Records (CDRs), automatically collected by telecom operators are records of verified, time-stamped one-to-one communication. They are particularly useful to understand one-to-one communication patterns, as well as the dynamics of the social networks that are reflected in such patterns. In this EPJ B Colloquium, Jari Saramäki and Esteban Moro present an overview of empirical results pertaining to the multi-scale nature of social dynamics and networks, as inferred from CDRs.
They begin with the shortest timescales and fastest dynamics, for example burstiness of call sequences between individuals, and then "zoom out" towards longer temporal and larger structural scales, from temporal motifs formed by correlated calls between multiple individuals to long-term dynamics of social groups. The authors conclude with a future outlook for CDR-based research, which faces a major challenge in the great diversity of new communication channels available and the propensity of the younger generations to adopt these new channels, even for voice. Future research will call for approaches that do not rely on a single source of data.
The authors identify emerging themes such as (i) the move from large data sets to smaller samples which compensate size with improvements in data quality and coverage of multiple channels, (ii) the shift from large aggregates to individuals, (iii) and the difficulty of sharing datasets which precludes the possibility to check the reproducibility of results.
Jari Saramäki and Esteban Moro (2015),
From seconds to months: an overview of multi-scale dynamics of mobile telephone calls,
European Physical Journal B, DOI: 10.1140/epjb/e2015-60106-6