I am an Assistant Professor in the Department of Government and the Program in Quantitative Social Science at Dartmouth College. I study political representation and partisanship, examining how legislators represent their constituents and how signals from legislators change both constituent and legislator behavior. In my work I develop novel experimental designs to show the causal effects of legislator action and partisanship on behavior. I contextualize these results with large-scale computational text analyses of legislator communication.
My work appears in the American Political Science Review, the American Journal of Political Science, Journal of Politics, Communication Research, Political Communication, and in a book published by Princeton University Press.
Areas of interest: Political Institutions, Political Behavior, Computational Social Science
The Partisanship of Bipartisanship: How Representatives Use Bipartisan Assertions to Cultivate Support
+ Abstract and paper
Abstract: How do representatives reconcile the actual content of legislation with often contradictory citizen expectations? To increase support, vote-seeking representatives attempt to shape how voters perceive the processes underpinning legislative outcomes. Representatives use rhetoric to position partisan legislation as bipartisan to cultivate an image of consensus building. Because constituents respond to presentations of the legislative process, representatives reap the benefits associated with bipartisanship, providing little incentive to engage in actual substantive compromise. Analysis of 304,763 congressional floor speeches shows that legislators evoke bipartisanship uniformly across the ideological spectrum and that no relationship exists between a legislator’s propensity for bipartisan action and their propensity for bipartisan rhetoric. Indeed, legislators who need to appear bipartisan---marginal legislators---are most likely to make bipartisan appeals. With experiments I show that bipartisan rhetoric increases support and decreases perceived ideological extremity---even for overtly partisan legislation with trivial opposition support.
The Tie That Divides: Cross-National Evidence of the Primacy of Partyism
With Shanto Iyengar, Stefaan Walgrave, Rafael Leonisio, Luis Miller and Oliver Strijbis+ Abstract and paper
Abstract: Using evidence from Great Britain, the United States, Belgium, and Spain, we demonstrate that in integrated and divided nations alike, citizens are more strongly attached to political parties than the social groups that the parties represent. In all four nations, partisans discriminate against their opponents and to a degree that exceeds discrimination against members of religious, linguistic, ethnic, or regional out groups. This pattern holds even when social cleavages are intense and the basis for prolonged political conflict. Partisan animus is conditioned by ideological proximity; partisans are more distrusting of parties furthest from them in the ideological space. The effects of partisanship on trust are also eroded when partisan and social ties collide. In closing, we consider the reasons that give rise to the strength of "partyism" in modern democracies.
How Words and Money Cultivate a Personal Vote: The Effect of Legislator Credit Claiming on Constituent Credit Allocation
American Political Science Review (November 2012)+ Abstract and paper
Abstract: Particularistic spending, a large literature argues, builds support for incumbents. This literature equates the amount spent with the credit constituents allocate to legislators. Yet, constituents lack the necessary information, expertise, and motivation to allocate credit based on the amount spent in the district. Rather, we show how legislators' credit claiming efforts--and not just money spent in the district--systematically affect how constituents allocate credit. We use a massive new collection of House press releases to characterize what legislators claim credit for, use innovative experimental designs to isolate the effect of those messages, and then a robust observational design to demonstrate the far-reaching effects of those statements. Together our results have broad implications for political representation and the empirical and theoretical study of particularistic spending and its effect on U.S. Congressional elections.
Fear and Loathing Across Party Lines: New Evidence on Group Polarization
American Journal of Political Science (2015)
With Shanto Iyengar+ Abstract and paper
Abstract: When defined in terms of social identity and affect toward copartisans and opposing partisans, the polarization of the American electorate has dramatically increased. We document the scope and consequences of affective polarization of partisans using implicit, explicit and behavioral indicators. Our evidence demonstrates that hostile feelings for the opposing party are ingrained or automatic in voters’ minds, and that affective polarization based on party is just as strong as polarization based on race. We further show that party cues exert powerful effects on non-political judgments and behaviors. Partisans discriminate against opposing partisans, and do so to a degree that exceeds discrimination based on race. We note that the willingness of partisans to display open animus for opposing partisans can be attributed to the absence of norms governing the expression of negative sentiment and that increased partisan affect provides an incentive for elites to engage in confrontation rather than cooperation.
The Limits of Partisan Prejudice
Journal of Politics (forthcoming)
With Yphtach Lelkes+ Abstract and paper
Abstract: Partisanship increasingly factors into the behavior of Americans in both political and non-political situations, yet the bounds of partisan prejudice are largely unknown. In this paper we systematically evaluate the limits of partisan prejudice using a series of five studies situated within a typology of prejudice. We find that partisan prejudice predicts promotion of hostile rhetoric, avoidance of members of the opposition, and a desire for preferential treatment for one's own party. However, even the most affectively polarized---those with the strongest disdain for the opposition---are no more likely to discriminate against the opposition than those with minimal levels of affective polarization.
Selective Exposure in the Age of Social Media: Endorsements Trump Partisan
Source Affiliation when Selecting Online News Media
Communication Research (December 2014)
With Solomon Messing+ Abstract and paper
Abstract: Much of the literature on polarization and selective exposure presumes that the internet exacerbates the fragmentation of the media and the citizenry. Yet, this ignores how the widespread use of social media changes news consumption. Social media provide readers a choice of stories from different sources that come recommended from politically heterogeneous individuals, in a context that emphasizes social value over partisan affiliation. Building on existing models of news selectivity to emphasize information utility, we hypothesize that social media’s distinctive feature, social endorsements, trigger several decision heuristics that suggest utility. In two experiments, we demonstrate that stronger social endorsements increase the probability that people select information, and that their presence reduces partisan selective exposure to levels indistinguishable from chance.
The Role of Persuasion in Deliberative Opinion Change
Political Communication (December 2015)+ Abstract and paper
Abstract: How does discussion lead to opinion change during deliberation? I formulate and test hypotheses based on theories of persuasion, and examine them against other possible sources of deliberative opinion change. Through detailed analysis of a nationally representative deliberative event I create a full discussion network for each small group that deliberated by recording who said what, the argument quality for what was said and to whom it was directed. I find that well-justified arguments made in the context of direct engagement between peers are a consistent predictor of opinion change. Individual-level persuasion, not knowledge-driven refinement or extremity, drives most opinion change. These results show that further deliberative research needs to account for persuasion when explaining deliberative opinion change.
Estimating Heterogeneous Treatment Effects and the Effects of Heterogeneous Treatments with Ensemble Methods
Political Analysis (forthcoming)+ Abstract and paper
Abstract: Randomized experiments are increasingly used to study political phenomena because they can credibly estimate the average effect of a treatment on a population of interest. But political scientists are often interested in how effects vary across sub-populations- heterogeneous treatment effects-and how differences in the content of the treatment affects responses-the response to heterogeneous treatments. Several new methods have been introduced to estimate heterogeneous effects, but it is difficult to know if a method will perform well for a particular data set. Rather than use only one method, we show how an ensemble of methods---weighted averages of estimates from individual models-accurately measure heterogeneous effects. Building on a large literature on ensemble methods, we show the close relationship between out of sample prediction and accurate estimation of heterogeneous treatment effects and demonstrate how pooling models leads to superior performance to individual methods across diverse problems. We apply the ensemble method to two experiments, illuminating how constituents reward and punish legislators for particularistic spending.
Can Pre-election Polls Influence Voting? Evidence from a Randomized Field Experiment
With David Vannette+ Abstract
Abstract: News coverage of elections focuses on the horserace to a greater degree than any other subject, and polls provide a critically important component of this coverage. The trend toward increased horserace coverage has been lamented on normative grounds by many scholars and journalism critics due to the resulting decline in policy and issue coverage during elections and the potential harm to voter knowledge. However, very little empirical research addresses the potential for positive effects of the proliferation of poll reporting on voting behavior. This article reports the results of a field experiment conducted during the 2012 election that examines the effects of poll information on candidate preferences and the decision to vote. The results suggest that candidate preferences are very stable but the decision to participate in politics by voting may be influenced by exposure horserace information in the form of pre-election polls. Importantly, this polling information may not have uniform effects. Experimentally manipulated polling information indicating a result that was consistent with the prevailing national trend did not significantly increase turnout. However, as the experimental poll results diverged from the national trend, significantly higher levels of voting were observed in response.