Robust Ideal Point Estimation with L0 Regularization

Published:Dec 31, 2025 05:29
1 min read
ArXiv

Analysis

This paper addresses a critical problem in political science: the distortion of ideal point estimation caused by protest voting. It proposes a novel method using L0 regularization to mitigate this bias, offering a faster and more accurate alternative to existing methods, especially in the presence of strategic voting. The application to the U.S. House of Representatives demonstrates the practical impact of the method by correctly identifying the ideological positions of legislators who engage in protest voting, which is a significant contribution.

Reference

Our proposed method maintains estimation accuracy even with high proportions of protest votes, while being substantially faster than MCMC-based methods.