Statistical Science

Forensic Analysis of the Venezuelan Recall Referendum

Raúl Jiménez

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The best way to reconcile political actors in a controversial electoral process is a full audit. When this is not possible, statistical tools may be useful for measuring the likelihood of the results. The Venezuelan recall referendum (2004) provides a suitable dataset for thinking about this important problem. The cost of errors in examining an allegation of electoral fraud can be enormous. They can range from legitimizing an unfair election to supporting an unfounded accusation, with serious political implications. For this reason, we must be very selective about data, hypotheses and test statistics that will be used. This article offers a critical review of recent statistical literature on the Venezuelan referendum. In addition, we propose a testing methodology, based exclusively on vote counting, that is potentially useful in election forensics. The referendum is reexamined, offering new and intriguing aspects to previous analyses. The main conclusion is that there were a significant number of irregularities in the vote counting that introduced a bias in favor of the winning option. A plausible scenario in which the irregularities could overturn the results is also discussed.

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Statist. Sci. Volume 26, Number 4 (2011), 564-583.

First available in Project Euclid: 28 February 2012

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Election forensics Venezuelan presidential elections Benford’s Law multivariate hypergeometric distribution


Jiménez, Raúl. Forensic Analysis of the Venezuelan Recall Referendum. Statist. Sci. 26 (2011), no. 4, 564--583. doi:10.1214/11-STS375.

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