September 30, 2015

Tree-based models for political science data

In this paper, we introduce a family of tree-based nonparametric techniques that are often more appropriate than traditional methods for confronting these data challenges. In particular, tree models are extremely effective for detecting nonlinearities and interactions in datasets with many (potentially irrelevant) covariates.

Forthcoming at American Journal of Political Science.  With Santiago Olivella
Local copy (pdf) | Supplemental Information (pdf) 

September 30, 2015

The Effects of Congressional Staff Networks in the U.S. House of Representatives

In this paper, we use a novel dataset of comprehensive longitudinal employment records from the U.S. House of Representatives to show that Congressional staff -- whose careers often cross multiple offices -- help disseminate legislative expertise within parties and develop and reinforce the voting patterns of legislators.

Forthcoming at the Journal of PoliticsWith Brendan Nyhan.
Local Copy (pdf)

September 29, 2015

An Informed Forensics Approach to Detecting Vote Irregularities

We deploy a Bayesian additive regression trees (BART) model -- a machine-learning technique -- on a large cross-national dataset to explore the dense network of potential relationships between various forensic indicators of anomalies and electoral fraud risk factors, on the one hand, and the likelihood of fraud, on the other. 

2015. Political Analysis 23 (4): 488-505 With Santiago Olivella, Joshua D. Potter, and Brian F. Crisp.


September 29, 2015

Static Stability and Evolving Constraint

Preference Stability and Ideological Structure in the Mass Public

Using panel surveys from the 1970s, 1990s, and 2010s, we conduct a multi-trait multi-method (MTMM) confirmatory factor analysis of citizen preferences in multiple issue areas. Our results reveal a surprising degree of preference stability in all three time periods across many policy domains. Further, our results reveal increasing levels of ideological thinking over time and that these patterns of stability and coherence hold across subpopulations defined by levels of sophistication.

2016. American Politics Research 44 (3): 415-447. With Melanie Freeze.
Local Copy (pdf) | External Link

September 28, 2015

Does Public Financing Affect Judicial Behavior?

Evidence From the North Carolina Supreme Court

Applying a difference-in-differences research design, we provide evidence that justices who opted into public financing became relatively less favorable toward attorney donors. We also find partial support for our hypothesis that participating justices became more moderate in their voting patterns. 

2016. American Politics Research 44 (4) 587-617. With Morgan Hazelton and Brendan Nyhan.  
Local Copy (pdf) | External Link

March 28, 2014

Connecting the Candidates

Consultant Networks and the Diffusion of Campaign Strategy in American Congressional Elections
We conduct the first systematic analysis of how consultants help disseminate campaign tactics among their clients using data from U.S. Congressional elections.

2015. American Journal of Political Science 59 (2) 292-308. With Brendan Nyhan.
Local copy (pdf) | External Link
January 1, 2014

Polarization and Ideology

Partisan Sources of Low-Dimensionality in Scaled Roll-Call Analyses

In this article, we conduct Monte Carlo simulations altering assumptions regarding the dimensionality and distribution of member preferences and scale the resulting roll-call matrices. Our simulations show that party polarization generates misleading evidence in favor of low-dimensionality.

2014. Political Analysis 22 (4) 435-456. With John H. Aldrich and David Sparks
Local Copy (pdf) | External Link


October 30, 2012

Ensemble Predictions of the 2012 US Presidential Election

2012. PS: Political Science and Politics 45 (4): 651-654. With Florian Hollenbach and Michael D. Ward.

We create an ensemble prediction of the upcoming election. We combine the intuition, theories, and concepts implicit in all of the forecasting models presented in 2012 PS Symposium to make an accurate out-of-sample prediction. Without arbitrating between models and theories, we aim to aggregate them solely with an eye toward increasing our chances of getting it right.

2012. PS: Political Science and Politics 45 (4): 651-654. With Florian Hollenbach and Michael D. Ward.
External link (pdf)