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arXiv · 2503.22045

Parapolitics and Roll-Call Voting in Colombia: A Bayesian Euclidean and Spherical Spatial Analysis

Juan Sosa·Carolina Luque·Juan Valero
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Abstract

This study presents a Bayesian spatial voting analysis of the Colombian Senate during the 2006-2010 legislative period, leveraging a newly constructed roll-call dataset comprising 147 senators and 136 plenary votes. We estimate legislators' ideal points under two alternative geometric frameworks: A traditional Euclidean model and a circular model that embeds preferences on the unit circle. Both models are implemented using Markov Chain Monte Carlo methods, with the circular specification capturing geodesic distances and von Mises-distributed latent traits. The results reveal a latent structure in voting behavior best characterized not by a conventional left-right ideological continuum but by an opposition-non-opposition alignment. Using Bayesian logistic regression, we further investigate the association between senators' ideal points and their involvement in the para-politics scandal. Findings indicate a significant and robust relationship between political alignment and para-politics implication, suggesting that extralegal influence was systematically related to senators' legislative behavior during this period.

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Juan Sosa, Carolina Luque, Juan Valero. 2025-03-27. Parapolitics and Roll-Call Voting in Colombia: A Bayesian Euclidean and Spherical Spatial Analysis. https://arxiv.org/abs/2503.22045

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