We provide a definition of institutionalism and a schematic account that differentiates between institutional theories (in which institutions are exogenous) and theories of institutions, in which some (but not necessarily all) institutions are endogenous. Our primary argument is that...

A spatial theory of the comparative consequences of unified and divided government clarifies the relationship between institutions, partisanship and gridlock. Under formally specified conditions, executive and legislative institutions are shown to inhibit but not prohibit the convergence of...

With an emphasis on the U.S. Congress, this essay addresses political economy approaches to the study of legislative organization. Simple models provide a foundation for more sophisticated studies of one of two problems: how coalitions of intense minorities pass policies that reflect gains from...

Credible tests of hypotheses about power require credible measures of power. Roll rates</EM> purport to measure the relative power of the parties in legislatures. This article develops and employs a baseline model to assess roll rates. Although on the surface roll rates have some intuitively...

What fundamental forces account for procedural change in majoritarian voting institutions? I address this question by defining majoritarianism as a variable with two attributes: a numeric component that sets a threshold of assent among decision-makers, and a contextual component that defines the...

Four pure types of legislative organization are characterized as data generating processes for commonly used measures of preferences or, in the spatial vernacular, ideal points. The types of legislative organization are differentiated by their partisan versus nonpartisan nature of agenda...