The Journal of Politics


Estimating Proposal and Status Quo Locations Using Voting and Cosponsorship Data

Michael Peress

University of Rochester


Theories of lawmaking generate predictions for the policy outcome as a function of the status quo. These theories are difficult to test because the widely applied ideal point estimation techniques do not recover the locations of proposals or status quos. Instead, such techniques only recover cutpoints. This limitation has meant that most existing tests of theories of lawmaking have been indirect in nature. I propose a method of directly measuring ideal points, proposal locations, and status quo locations on the same scale, by employing a combination of voting data, bill and amendment cosponsorship data, and the congressional record. My approach works as follows. First, we can identify the locations of legislative proposals (bills and amendments) on the same scale as voter ideal points by jointly scaling voting and cosponsorship data. Next, we can identify the location of the final form of the bill using the location of the last successful amendment (which we already know). If the bill was not amended, then the final form is simply the original bill location. Finally, we can identify the status quo point by employing the cutpoint we get from scaling the final passage vote. To implement this procedure, I automatically coded data on the congressional record available from I apply this approach to recent sessions of the U.S. Senate and use it to test the implications of competing theories of lawmaking.


  Michael Peress in an Associate Professor of Political Science at the University of Rochester.