Flowminder and NCell jointly agreed to study the population flows in post-earthquake situation by recording a location for each user (through SIM cards) at two different times, and then counting the number of users who moved from one location to another.
Set-up included a high-specification Linux analysis server (with 128GB of RAM and over 20TB of disk space) within Ncell’s data centre. The analysis consisted of a series of preprocessing steps automatically run for each new day’s Call Detail Record (CDR) data, followed by separate analyses designed to investigate particular aspects of mobility after the earthquake. Each day’s CDRs were provided by early morning the following day and historical data back to January 2015 were also provided. The preprocessing steps were designed to reduce this raw CDR data (approximately 12GB of CSV files per day).
This collaborative enable a response system during the crisis (natural disasters, diseases outbreaks) with an established coordination among government, mobile network providers and humanitarian communities. The same method was adopted to map the population mobility, displacement and impacted areas in July 2016.