During the COVID-19 crisis, the French National Institute of Statistics and Economic Studies (INSEE) used aggregated and anonymous counting indicators based on network signaling data of three of the four mobile network operators (MNOs) in France to measure the distribution of population over the territory during and after the lockdown and to enrich the toolbox of high-frequency economic indicators used to follow the economic situation. INSEE’s strategy was to combine information coming from different MNOs together with the national population estimates it usually produces in order to get more reliable statistics and to measure uncertainty. This paper relates and situates this initiative within the long-term methodological collaborations between INSEE and different MNOs, and INSEE, Eurostat, and some other European national statistical institutes (NSIs). These collaborations aim at constructing experimental official statistics on the population present in a given place and at a given time, from mobile phone data (MPD). The COVID-19 initiative has confirmed that more methodological investments are needed to increase relevance of and trust in these data. We suggest this methodological work should be done in close collaboration between NSIs, MNOs, and research, to construct the most reliable statistical processes. This work requires exploiting raw data, so the research and statistical exemptions present in the general data protection regulation (GDPR) should be introduced as well in the new e-privacy regulation. We also raise the challenges of articulating commercial and public interest rationales and articulating transparency and commercial secrets requirements. Finally, it elaborates on the role NSIs can play in the MPD valorization ecosystem.

Coastal–highland relationships were important in the development, expansion, and collapse of ancient societies in Nasca, Peru. Connections between the regions began with the earliest occupants and extended through Inca rule; they consisted of the exchange of goods, sharing of ideas, migration, and political dominance. By the end of the Early Intermediate period (Late Nasca, AD 500–650), highland relationships intensified, and during the Middle Horizon (AD 650–1000), Nasca for the first time came under highland control as the Wari Empire brought transformations to the region. By the end of the Middle Horizon, Wari had collapsed, and much of the Nasca drainage was abandoned. People emigrated from the region, probably because of drought coupled with political and social instability. When Nasca was repopulated (ca. AD 1200) in the Late Intermediate period, a new type of society developed that was likely the result of large numbers of highland immigrants.

This study analyzes circumstances tied to the implementation of the Dayton Agreement’s provision for the reunification of Sarajevo. Three months after the signing, Sarajevo was again a united city territorially, but pre-war inhabitants of Sarajevo who identified themselves as Serbs were almost entirely absent from the reunited town under the control of the Federation government. This article addresses the causes of the flight of the Serbs, who had been living in Sarajevo’s suburbs before the start of the Bosnian war and stayed, in their view, to defend their homes. I argue that the incentives that led a majority of Sarajevan Serbs to leave the city and its surroundings were the result of actions not only of the Serb leadership but also of Bosniak leaders and the international community. Our analysis is complementary to the scholarship examining the impact of massive population migrations and displacement in the aftermath of conflicts. I analyze the dynamics of Sarajevo’s unification within the Federation and its consequences, demonstrating that once a partition is accepted at a higher level, it is almost impossible to prevent its emergence on a local level.