Explaining Policy Ties in Presidential Congresses: A Network Analysis of Bill Initiation Data



Policy networks formed by co-authoring and co-sponsoring bills reflect one of the most important types of connection legislators develop while in office. We expect that in presidential countries, the probability of a tie between two legislators should be influenced by partisan membership, territorial linkages and the policy areas in which they develop expertise. Given the complex nature of relational data and the particular characteristics of bill initiation networks, we propose a new approach – bootstrapping an exponential graph model using augmented data reflective of the frequency of ties – to address the challenges of thinning dense networks.