Despite growing attention to the role of social context in determining political participation, the effect of the structure of social networks remains little examined. This article introduces a model of interdependent decision making within social networks, in which individuals have heterogeneous motivations to participate, and networks are defined via a qualitative typology mirroring common empirical contexts. The analysis finds that some metrics for networks' influence-size, the prevalence of weak ties, the presence of elites-have a more complex interaction with network structure and individual motivations than has been previously acknowledged. For example, in some contexts additional network ties decrease participation. This presents the potential for selection bias in empirical studies. The model offers a fuller characterization of the role of network structure and predicts expected levels of participation across network types and distributions of motivations as a function of network size, weak and strong ties, and elite influence.

No abstract

No abstract

That neither the assumptions nor the predictions of standard government formation models entirely correspond to empirical findings has led some to conclude that theoretical accounts of government formation should be reconsidered from the bottom up. We take up this challenge by presenting a zero-intelligence model of government formation. In our model, three or more parties that care about office and policy make random government proposals. The only constraints that we impose on government formation correspond to the two binding constitutional constraints that exist in all parliamentary systems: an incumbent government always exists and all governments must enjoy majority legislative support. Despite its deliberately limited structure, our model predicts distributions over portfolio allocation, government types, and bargaining delays that approach those observed in the real world. Our analysis suggests that many formation outcomes may result from the institutional foundation of parliamentary democracies, independent of the strategic behavior of party leaders.

A review of international terrorist activity reveals a pattern of financially strapped operatives working for organizations that seem to have plenty of money. To explain this observation, and to examine when restricting terrorists' funds will reduce their lethality, we model a hierarchical terror organization in which leaders delegate financial and logistical tasks to middlemen, but cannot perfectly monitor them for security reasons. These middlemen do not always share their leaders' interests: the temptation exists to skim funds from financial transactions. When middlemen are sufficiently greedy and organizations suffer from sufficiently strong budget constraints, leaders will not fund attacks because the costs of skimming are too great. Using general functional forms, we find important nonlinearities in terrorists' responses to government counterterrorism. Restricting terrorists' funds may be ineffective until a critical threshold is reached, at which point cooperation within terrorist organizations begins to break down and further government actions have a disproportionately large impact.