Hierarchies are pervasive in political settings. From judges to elected politicians, from activists to bureaucrats, political agents compete to be promoted to higher positions. This paper studies political tournaments and their impact on key aspects of political performance: accountability and...

Online communities exist in many forms and sizes. Yet, there is limited insight into why some online communities are sustainable, while others disappear. We find that in order to maintain sustainability, online communities exhibit a typical hierarchical social circle structure that balances...

There is a regrettable tendency to equate social conservatism with religious adherence. Nowhere does this occur more than in the Muslim world, where conservatives are closely associated with adherence to shari’a. The more unyielding the conservative, the “stricter” the supposed adherence...

The concentration of global wealth, power, knowledge, authority and prestige continues unabated. Antitrust enforcement has been at the heart of debates on combating increasing inequality. Yet, the transformation possibilities have been overstated, while its impact has been paralyzed by...

Social status hierarchy is a prominent topic in sociology, but a complete theoretical understanding of its process has been lacking. Using game theory and social network theory, Gould showed that status hierarchy can be considered as a type of equilibrium wherein players assign attachments to...

We analyze the classic problem of sustaining trust when cheating and leaving trading partners is easy, and outside enforcement is difficult. We construct equilibria where individuals are loyal to smaller groups – communities – that allow repeated interaction. Hierarchies provide incentives...