Measuring legislative effectiveness in US Congress often focuses on individual characteristics like seniority, partisanship, and leadership roles. However, this article examines how legislators' social connections—specifically their alumni networks—affect effectiveness using a novel model.

Methodology & Data

The study employs network analysis of cosponsorship links during the 109th-113th US Congresses (1985–2005). To address potential endogeneity, it implements an original two-step Heckman correction strategy leveraging legislators' alumni networks as instrumental variables.

Key Findings

The research reveals that social connections significantly predict legislative effectiveness—beyond traditional factors like seniority or committee membership. Legislators with stronger alumni network ties tend to be more effective in their policy work.

Network Influences

Researchers also analyze how individual characteristics shape these network effects:

• Seniority interacts differently with networks depending on party control

• Committee assignments amplify the impact of social connections

• Leadership positions modify network effectiveness differently across parties

This demonstrates that political science must consider social networks as a fundamental determinant of legislative power and influence.