Can digital information and communication technology (ICT) foster mass political mobilization? We use a novel geo-referenced dataset for the entire African continent between 1998 and 2012 on the coverage of mobile phone signal together with geo-referenced data from multiple sources on the occurrence of protests and on individual participation in protests to bring this argument to empirical scrutiny. We find that while mobile phones are instrumental to mass mobilization, this only happens during economic downturns, when reasons for grievance emerge and the cost of participation falls. The results are in line with insights from a network model with imperfect information and strategic complementarities in protest occurrence. Mobile phones make individuals more responsive to both changes in economic conditions -a mechanism that we ascribe to enhanced information -and to their neighbors' participation -a mechanism that we ascribe to enhanced coordination. from useful comments by seminar participants at several institutions. We are also very grateful to John Allen at CollinsBartholomew, Timothy Thomas at IFPRI and Susmita Dasgupta at the World Bank for their invaluable assistance with the mobile phone data, and to Carmen Alpin Lardies for her invaluable help with the Afrobarometer data. Users interested in accessing the mobile phone coverage data should consult the attached material for conditions and further instructions.

Abstract-We examine the effect of oil price fluctuations on democratic institutions over the 1960-2007 period. We also exploit the very persistent response of income to oil price fluctuations to study the effect of persistent (oil-price-driven) income shocks on democracy. Our results indicate that countries with greater net oil exports over GDP see improvements in democratic institutions following upturns in international oil prices. We estimate that a 1 percentage point increase in per capita GDP growth due to a positive oil price shock increases the Polity democracy score by around 0.2 percentage points on impact and by around 2 percentage points in the long run. The effect on the probability of a democratic transition is around 0.4 percentage points.