This project maps national mobility patterns in Namibia and Senegal using data sources of call detail records (CDRs) and census data. By comparing the results gained by analysing both sources, the team aimed to find relationships between short- and long-term migration movements, using CDRs for insights into short-term movements and census data for long-term migration. In addition to a finer temporal resolution, using CDR data allowed the team to draw conclusions on factors leading to migration, such as social contacts, geographic distance, and seasons.
In general, the results showed that relationships between short- and long-term migration are strongest for holidays; meaning, long-term migrants tend to spend vacations in hometowns or family members come visit in the new place of residence. Furthermore, the analysis of the CDR data showed that social contacts and geographic distance are the main criteria based on which people choose where to spend a short trip. Overall, this project successfully combined an innovative with a traditional data source to gain insights of individual mobility behaviour. It can be replicated to multiple geographic contexts, especially where mobile phones are widespread and CDRs can be made available to effectively complement (missing) census data.
(Image: © Data-Pop Alliance)