Monitoring temporary populations through cellular core network data Fabio Manfredini, Paolo Tagliolato, Carmelo di Rosa - Department of Architecture and Planning, Polytechnic of Milan

1. Monitoring visitors and tourists through cellular core network data Fabio Manfredini , Paolo Tagliolato, Carmelo Di Rosa Laboratorio Analisi Dati e Cartografia Dipartimento di Architettura e Pianificazione, Politecnico di Milano ICCSA 2011 CTP Workshop Santander 19 – 22 October 2011

2. The research has been carried out by the Department of Architecture and Planning of the Politecnico di Milano for Telecom Italia, the main Italian mobile phone operator. The aim was to assess the contribution of cellular phone traffic data for understanding and analyzing urban dynamics and to propose possible uses of this kind of information in urban analysis. The coherence with traditional data source has been tested in order to verify the reliability of mobile data in describing city use and patterns. The work was coordinated by Fabio Manfredini and Paola Pucci Paolo Tagliolato, Paolo Dilda, Paolo Beria, Carmelo Di Rosa and Eugenio Morello participated in the research. Outline of the research

3. Mobile phone data analysis – un-volonteered geography Data Research area Purpose Tracks of calls of individual phone users (active mobile positioning) Network science Study of geometrical patterns of the mobility of individuals (deprived of the specific geographical reference) Spatial distribution of cell phone network traffic intensity (derived from cellular network log files) Mobile landscapes Study of the density of use of a territory Spatial and temporal distribution of GSM active clients – switched on mobile phone Monitoring tourists and visitors

7. Spatial and temporal patterns during the 2009 Int. Design Week The special event Typical weekday Special event / Typical weekday ratio Nightime / Daytime ratio Interpretation of spatial and temporal patterns is a crucial task.

8. Mobile switching center (MSC), is the primary service delivery node for GSM, responsible for routing voice calls and SMS. It also records information on the mobility of subscribers by updating the position of mobile devices in the HLR (Home Location Register), which contains all subscriber information. GSM architecture

10. MSC Service areas Map of the Lombardia region’s MSC Service Area Zoom on the Milano Urban region Statistics for the Lombardia region MSC service areas (square Km) The service area of each MSC has a variable size depending on the number of GSM tower cells served and on the intensity of mobile phone traffic generated inside it. Average 1591,988658 Median 772,2885667 Standard deviation 2148,758884 Interval 7586,93098 Min 27,43751191 Max 7614,368492 Number 15

12. Monthly Milan city rithms – April 2010 Week-end Easter 2010 hourly variation of active clients in Milan MSC service area for the period April, 1st 2010 – April, 30th 2010.

14. MSC active clients vs foreign residents The 10 most numerous nationality in the Lombardia Region from 2009 official statistics (left) and from MSC Register during the September 7 – 21, 2009 period (right) Nationality Percentage (active clients) German 22.9% Swiss 15.1% English 6.9% French 6.4% Romanian 5.9% Polish 5.8% Spanish 4.3% Dutch 2.7% Czech Republic 2.2% Austrian 2.1% Nationality Percentage (residents) Romanian 35.5% Moroccan 29.5% Albanian 27.1% Egiptian 15.9% Filipina 12.3% Chinese 11.3% Indian 11.1% Ecuador 10.8% Peruvian 10.0% Ucrain 8.7%

15. Statistics on the occupancy of collective tourist accommodation refer to the number of arrivals (at accommodation establishments) and the number of nights spent by residents and non-residents, separated into establishment type or region; annual and monthly statistical series are available. This information is available at the provincial spatial scale and underestimates the dimension of phenomena, because it considers only tourists or visitors who go to official structures. A large proportion of temporary visitors are therefore excluded . there are about 500,000 visitors per year who are not counted by statistics because they spend nights by friends or by informal touristic structures (Observatory of Tourism – Milan). Tourism statistic

16. Escludendo le SIM Italiane si evidenziano due eventi. Pasqua: 4-5 aprile; Salone del mobile: 14-19 aprile (64% in più della media degli altri giorni di aprile) Foreign active clients during April 2010 Int. Design week Easter 2010 Garda Lake MSC Milano MSC

17. Foreign active clients during the 2010 International Design Week

18. Foreign active clients during the 2010 International Design Week: most numerous nationalities Nationality Percentage % French 9,8% Swiss 9,2% United Kingdom 8,7% Spain 8,0% German 7,5% Russian Federation 5,6% USA 4,0%

19. Despite of the dimension of the MSC service area, the data were able to catch the foreign trends as a phenomenon visible at a urban scale. For major events, active clients can provide an important tool for monitoring visitors and tourists, for evaluating the attractiveness of a big event, for evaluating its economic impact and for providing new touristic and business services directed to specific nationalities. There is a strong need of updated knowledge on urban attractiveness, a major component of global cities competition which is hardly intercepted by standard surveys. Innovative methods are therefore required for measuring and monitoring tourists and visitors at the different urban scales. MSC active clients data seems to be promising for visitors and tourist monitoring because it provides information that currently institutional sources do not offer. Conclusion

20. This study suggests that cell-phone-network data, due to their temporal and spatial resolution, has the potential to drastically change the way we view and understand the urban environment and the urban populations . Mobile phone data analysis is a multidisciplinary topic: data mining techniques, representation, programming, network analysis, urban analysis are some of the components of this “new” scientific field. We collected ideas and proposals from public and private bodies on possible applications of this approach to different topics such as event management, civil protection, mobility monitoring, urban rhythms analysis and mapping . Conclusion

21. Thank you! [email_address]