Using CDR Data to Understand Post-pandemic Mobility Patterns

During the COVID-19 pandemic, the measures imposed to slow the spread of the virus had a profound impact on population dynamics around the world, producing unprecedented changes in mobility. Spatial data on human activity, including Call Detail Records (CDRs), have become a valuable source of information for understanding those changes. In this paper we study the population's mobility after the first wave of the pandemic within Portugal, using CDR data. We identify the movements and stops of the citizens, at an antenna level, and compare the results in the first months after the lifting of most of the contingency measures with the same period of the following year, highlighting the advantages of using CDRs to analyze mobility in pandemic contexts. Results based on two mobile phone datasets showed a significant difference in mobility in the two periods.