This article was originally published in Finnish in issue 4/2025 of Yliopisto magazine.
In 2006, Rein Ahas, Professor of Geography at the University of Tartu, acquired access to mobile phone data from an Estonian telecommunications company. This gave the then student Olle Järv a direction for his researcher career.
From then on, Järv has used anonymised mobile phone datasets to investigate people’s mobility.
“The data reveal people’s locations and travel flows in real time. They allow you to see the mobility routines of locals and tourists.”
Ten years ago Järv transferred to the University of Helsinki as a postdoctoral researcher in geoscientist Tuuli Toivonen’s Digital Geography Lab. Among other topics, Järv has investigated multi-locality, service accessibility and segregation.
Digital datasets have opened up new perspectives. For example, spatial segregation has usually been investigated based on where people live, not where they spend their time.
“Data show where a mobile phone is at night and where it moves by day. This provides a temporal dimension to research on the location of population groups.”
In recent years, Järv has studied areas transcending the internal borders of the EU, where people move for work, shopping or leisure between countries. He studies these functional boundaries with the help of location-enabled social media data.
“Social media allow us to distinguish between locals and tourists. Once we recognise locals, who cross the border on a regular basis, we will understand how border regions function.”
Cross-border regions defined in the EU’s funding programmes do not always correspond to people’s actual everyday mobility. Järv’s study may help in defining cross-border regions and better guiding their development.
On 20 May Järv received the prestigious Research Council of Finland Award for a junior researcher demonstrating open-mindedness in their work. He remains interested in studying societal and human mobility through digital footprints.
“I’ve only just scratched the surface. In future, I want to expand my research on cross-border mobility to a global level.”
Yliopisto is a scholarly magazine published by the University of Helsinki and committed to the journalistic guidelines of the Council for Mass Media in Finland.