The best empirical research in political science clearly defines substantive parameters of interest, presents a set of assumptions that guarantee its identification, and uses an appropriate estimator. We argue for the importance of explicitly integrating rigorous theory into this process and...

The current polarization of elites in the U.S., particularly in Congress, is frequently ascribed to the emergence of cohorts of ideologically extreme legislators replacing moderate ones. Politicians, however, do not operate as isolated agents, driven solely by their preferences. They act within...

In this paper we argue that the number of candidates running for public office, their ideological differentiation, and the intensity of campaign competition are all naturally intertwined, and jointly determined in response to the incentives provided by the electoral system. We propose a simple...

This paper links the theory of interest groups influence over the legislature with that of congressional control over the judiciary. The resulting framework reconciles the theoretical literature of lobbying with the negative available evidence on the impact of lobbying over legislative outcomes,...

Democratic representation is constrained by the alternatives available to voters. In this paper, we develop a methodology to gauge the extent to which the "supply side" of politics hinders voter welfare. Using rich data on thousands of candidates in three Brazilian legislative elections, we...