This paper explains why firms with identical opportunities may use different technologies and offer different wages. Our key assumption is that workers must engage in costly search in order to gather information about jobs (Stigler (1961)). In equilibrium, some firms adopt high fixed cost, high productivity technologies, offer high wages, and fill job openings quickly. Other firms adopt less capital-intensive technologies and offer low wages, hiring mostly uninformed workers. In equilibrium, the amount of wage dispersion leaves workers indifferent about whether to gather information, and the fraction of informed workers leaves firms indifferent about their wage and technology choice. We show that worker search, which would appear to be a rent-seeking activity in partial equilibrium, may be efficiency-enhancing in general equilibrium.

We study the evolution of a social norm of “cooperation” in a dynamic environment. Each agent lives for two periods and interacts with agents from the previous and next generations via a coordination game. Social norms emerge as patterns of behaviour that are stable in part due to agents' interpretations of private information about the past, influenced by occasional commonly observed past behaviours. For sufficiently backward-looking societies, history completely drives equilibrium play, leading to a social norm of high or low cooperation. In more forward-looking societies, there is a pattern of “reversion” whereby play starting with high (low) cooperation reverts towards lower (higher) cooperation. The impact of history can be countered by occasional “prominent” agents, whose actions are visible by all future agents and who can leverage their greater visibility to influence expectations of future agents and overturn social norms of low cooperation.

Voters often dismantle constitutional checks and balances on the executive. If such checks and balances limit presidential abuses of power and rents, why do voters support their removal? We argue that by reducing politician rents, checks and balances also make it cheaper to bribe or influence politicians through non-electoral means. In weakly institutionalized polities where such non-electoral influences, particularly by the better organized elite, are a major concern, voters may prefer a political system without checks and balances as a way of insulating politicians from these influences. When they do so, they are effectively accepting a certain amount of politician (presidential) rents in return for redistribution. We show that checks and balances are less likely to emerge when the elite is better organized and is more likely to be able to influence or bribe politicians, and when inequality and potential taxes are high (which makes redistribution more valuable to the majority). We also provide case study evidence from Bolivia, Ecuador, and Venezuela consistent with the model.

We study the (perfect Bayesian) equilibrium of a sequential learning model over a general social network. Each individual receives a signal about the underlying state of the world, observes the past actions of a stochastically generated neighbourhood of individuals, and chooses one of two possible actions. The stochastic process generating the neighbourhoods defines the network topology. We characterize pure strategy equilibria for arbitrary stochastic and deterministic social networks and characterize the conditions under which there will be asymptotic learning—convergence (in probability) to the right action as the social network becomes large. We show that when private beliefs are unbounded (meaning that the implied likelihood ratios are unbounded), there will be asymptotic learning as long as there is some minimal amount of “expansion in observations”. We also characterize conditions under which there will be asymptotic learning when private beliefs are bounded.