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Paper

Racial Polarization and Turnout in Louisiana: New Insights from Aggregate Data Analysis Palmquist, Bradley Voss, D. Stephen Uploaded 00-00-0000 Keywords ecological inference aggregate data turnout South racial polarization redistricting Abstract This paper applies recent developments in aggregate data analysis to newly assembled precinct-level datasets for Louisiana. We validate the usefulness of these methods for answering common voting behavior questions, such as estimating racial polarization/cohesion and predicting racial turnout rates, by applying them to known crosstabulations of turnout by race and party in Louisiana. Then we take the analysis a step further to show how the methods can be used to estimate unknown statistics relevant to redistricting litigation (and their uncertainty) using as much information as possible. In addition to the methodological insights, we draw some substantive conclusions about racial voting behavior and racial mobilization in the South.

2

Paper

Polarization and Political Violence Penubarti, Mohan Asea, Patrick Uploaded 07-12-1996 Keywords polarization political violence extreme bounds analysis Abstract We explore the implications of a new notion of inequality --- polarization --- for the incidence and level of political violence. A society is said to be polarized when its members can be classified into different clusters, with each cluster being similar in terms of the attributes of its members (intra--group homogeneity) but with different clusters having members with dissimilar attributes (inter--group heterogeneity). The notion of polarization provides an important conceptual breakthrough in understanding inequality in societies because a society may be facing a decrease (increase) in inequality while at the same time experiencing an increase (decrease) in polarization. We conduct empirical analysis on a large sample of countries to demonstrate the positive link between polarization and political violence. In contrast, traditional measures of inequality perform poorly with the introduction of polarization in the model specification. Additionally, we conduct global sensitivity analysis to explore the robustness of the polarization measure to reasonable changes in the conditioning information set.

3

Paper

Partisans without constraint: Political polarization and trends in American public opinion Gelman, Andrew Baldassarri, Delia Uploaded 07-06-2007 Keywords issue alignment partisanship polarization Abstract Political polarization is commonly measured using the variation of responses on an individual issue. By this measure, research has shown that---despite many commentators' concerns about increased polarization---Americans' attitudes have become no more variable in recent decades. What has changed in the electorate is its level of partisanship. We define a new measure of political polarization as increased correlations in political attitudes and we distinguish between issue partisanship---the correlation of issue attitudes with party ID or ideology---and issue alignment---the correlation between pairs of issues. Using the National Election Studies (1972-2004), we find issue alignment to have increased by only 2 percentage points in correlation per decade. Issue partisanship has increased more than twice as fast, thus suggesting that changes in people's attitudes correspond more to a re-sorting of party labels among voters than to greater constraint on issue attitudes. Since parties are more polarized, they are now better at sorting individuals along ideological lines. Increased issue partisanship, in a context of persistently low issue constraint, might give greater voice to political extremists and single-issue advocates, and amplify dynamics of unequal representation.

4

Poster

Comparing Opinions and Preferences across States and Regions: The Fallacy of using Ideological Responses Cormack, Lindsey Nagler, Jonathan Uploaded 07-20-2012 Keywords ideology polarization public opinion Abstract We are interested in differences in ideology and preferences on policies across red and blue states, and across people who say they are liberals versus conservatives. We make several points about measurement of ideology and issue preferences, all in the context of `polarization'. First, the use of ideology for measuring polarization is quite dangerous as the typical ideology question has no fixed scale -- allowing respondents to interpret it quite differently across regions or groups. Second, ideology also has a potential dimensionality problem: it is fundamentally a projection of many dimensions (or issues) onto one dimension, thus allowing respondents to weight lower level dimensions differently across regions or groups. Taken together, this suggests that an electorate may be polarized on some issues, but not on other issues. This could be because the issues exist on distinct dimensions. Or, we could find issues that lie on the same dimensions, but some are simply more discriminating than others. In such cases, `polarization' would exist on the more discriminating issue, but not on the less-discriminating issue. Thus polarization, in the absence of a clear definition, will likely to continue to exist in the eye of the beholder.