On Partisan Bias

Kevin Lewis

November 24, 2009

Political partisanship influences perception of biracial candidates' skin tone

Eugene Caruso, Nicole Mead & Emily Balcetis
Proceedings of the National Academy of Sciences, forthcoming

People tend to view members of their own political group more positively than members of a competing political group. In this article, we demonstrate that political partisanship influences people's visual representations of a biracial political candidate's skin tone. In three studies, participants rated the representativeness of photographs of a hypothetical (Study 1) or real (Barack Obama; Studies 2 and 3) biracial political candidate. Unbeknownst to participants, some of the photographs had been altered to make the candidate's skin tone either lighter or darker than it was in the original photograph. Participants whose partisanship matched that of the candidate they were evaluating consistently rated the lightened photographs as more representative of the candidate than the darkened photographs, whereas participants whose partisanship did not match that of the candidate showed the opposite pattern. For evaluations of Barack Obama, the extent to which people rated lightened photographs as representative of him was positively correlated with their stated voting intentions and reported voting behavior in the 2008 Presidential election. This effect persisted when controlling for political ideology and racial attitudes. These results suggest that people's visual representations of others are related to their own preexisting beliefs and to the decisions they make in a consequential context.


Assessing Partisan Bias in Federal Public Corruption Prosecutions

Sanford Gordon
American Political Science Review, November 2009, Pages 534-554

The 2007 U.S. Attorney firing scandal raised the specter of political bias in the prosecution of officials under federal corruption laws. Has prosecutorial discretion been employed to persecute enemies or shield allies? To answer this question, I develop a model of the interaction between officials contemplating corruption and a prosecutor deciding whether to pursue cases against them. Biased prosecutors will be willing to file weaker cases against political opponents than against allies. Consequently, the model anticipates that in the presence of partisan bias, sentences of prosecuted opponents will tend to be lower than those of co-partisans. Employing newly collected data on public corruption prosecutions, I find evidence of partisan bias under both Bush (II) and Clinton Justice Departments. However, additional evidence suggests that these results may understate the extent of bias under Bush, while overstating it under Clinton.


Partisan Grading

Talia Bar & Asaf Zussman
Hebrew University Working Paper, November 2009

Grades affect resource allocation inside and outside the boundaries of the university. It is therefore important that they will provide reliable information on student abilities. However, a well known fact is that at any university there could be large differences in grading outcomes - across disciplines, departments, and instructors - which do not necessarily reflect differences in student abilities. In this paper we argue that differences in grading outcomes are associated with the political orientation of instructors. We test this hypothesis using a detailed dataset which merges student grades awarded at an elite research university in the United States with voter registration records from the county where the university is located. Our main findings are consistent with the existence of partisan grading preferences: conservatism is associated with a less egalitarian assignment of grades and with lower grades awarded to Black students relative to Whites.


The Absolutist Advantage: Sacred Rhetoric in Contemporary Presidential Debate

Morgan Marietta
Political Communication, October 2009, Pages 388-411

Sacred rhetoric invokes nonnegotiable convictions rather than reasoned consequences. This form of rhetoric, grounded in transcendent authority and moral outrage, provides an electoral advantage by inspiring greater political engagement and valorizing candidates in the eyes of voters. A study of the language employed in contemporary presidential debates from 1976 to 2004 illustrates that while Democrats made sacred appeals in a few political domains, Republicans employed sacred rhetoric more frequently across a broad range of issues. Democrats have relied more heavily on projected numbers and plans rather than protected values and bounds, often yielding to Republicans an absolutist advantage.


Explaining the President's Issue Based Liberalism: Pandering, Partisanship, or Pragmatism

Dan Wood & Han Soo Lee
Journal of Politics, October 2009, Pages 1577-1592

Past research attempting to explain the president's issue based liberalism has produced a muddled image. The most prominent work has been grounded in centrist theory, positing that presidents tailor their policy stances to mass preferences. Other work has also suggested that presidents cater to mass preferences, but only when their approval ratings are low or during elections. Still others find no relation between presidential issue liberalism and mass preferences, suggesting the importance of partisanship and pragmatism. We develop and validate a new measure of the president's issue based liberalism grounded in presidential rhetoric. We then test the centrist versus partisanship and pragmatism models of presidential liberalism using graphical and Box-Jenkins methods. Our graphical and statistical analyses firmly reject the centrist model and support an image of presidents as partisans whose public issue stances are sometimes moderated by pragmatic concerns. From the standpoint of democratic theory, our results raise questions about the nature of presidential representation in the American system.


A Longitudinal Test of the Model of Political Conservatism as Motivated Social Cognition

Miriam Matthews, Shana Levin & Jim Sidanius
Political Psychology, December 2009, Pages 921-936

Using data from a longitudinal study of college students, this study assessed the relationships among the threat perceptions of realistic threat and intergroup anxiety, the ideological motives of system justification and social dominance orientation (SDO), and political conservatism. Those who had higher perceptions of realistic threat and intergroup anxiety at the end of their first year of college showed higher levels of system justification and SDO at the end of their second and third years of college, controlling for precollege expressions of each variable. Higher levels of these two ideological motives at the end of students' second and third years of college were associated with more politically conservative attitudes at the end of students' fourth year of college, again controlling for precollege expressions. These longitudinal results are discussed in terms of a model of political conservatism as motivated social cognition.


The Politics of Causes: Motivated Reasoning and Attributions About Shooting Tragedies

Mark Joslyn & Donald Haider-Markel
University of Kansas Working Paper, September 2009

Individuals develop causal stories about the world around them that explain events, behaviors, and conditions. These stories may attribute causes to controllable components, such as individual choice, or uncontrollable components, such as broader forces in the environment. Here we employ motivated reasoning to understand causal attributions the 2007 Virginia Tech shooting tragedy. We argue that causal attributions stem from individual reasoning that is primarily motivated by existing dispositions and accuracy motives. Both motivations are present for attributions about the Virginia Tech shootings and we seek to understand their significance and whether dispositional motives condition accuracy drives. We are able to test several hypotheses using individual level survey data from a national survey to explain attributions about the 2007 shootings. Our findings suggest a substantial partisan divide on the causes of the tragedy and considerable differences between the least and most educated respondents. However, our analysis also reveal that education have virtually no influence on the attributions made by Republicans, but heightens the differences among Democrats. We discuss these findings for the public's understanding of the tragedy and more broadly for attribution research.


Party and Constituency Influence on Procedural and Final Passage Voting in the U.S. House

Stephen Jessee & Sean Theriault
University of Texas Working Paper, August 2009

Most analyses of congressional voting, whether theoretical or empirical, treat all roll call votes in the same way. We argue that such approaches mask considerable variation in voting behavior across different categories of votes. An examination of all recorded roll call votes in the U.S. House of Representatives from 1993 to 2008 reveals that members' voting behavior on procedural and final passage matters have become increasingly differentiated. We show that party has become increasingly important relative to constituency in dictating members' voting behavior, especially on procedural votes. These trends can account for much of the partisan polarization that has occurred during this time period.


Party Polarization in Congress: A Social Networks Approach

Andrew Scott Waugh, Liuyi Pei, James Fowler, Peter Mucha & Mason Porter
University of California Working Paper, July 2009

We use the network science concept of modularity to measure polarization in the United States Congress. As a measure of the relationship between intra-community and extra-community ties, modularity provides a conceptually-clear measure of polarization that directly reveals both the number of relevant groups and the strength of their divisions. Moreover, unlike measures based on spatial models, modularity does not require predefined assumptions about the number of coalitions or parties, the shape of legislator utilities, or the structure of the party system. Importantly, modularity can be used to measure polarization across all Congresses, including those without a clear party divide, thereby permitting the investigation of partisan polarization across a broader range of historical contexts. Using this novel measure of polarization, we show that party influence on Congressional communities varies widely over time, especially in the Senate. We compare modularity to extant polarization measures, noting that existing methods underestimate polarization in periods in which party structures are weak, leading to artificial exaggerations of the extremeness of the recent rise in polarization. We show that modularity is a significant predictor of future majority party changes in the House and Senate and that turnover is more prevalent at medium levels of modularity. We utilize two individual-level variables, which we call "divisiveness" and "solidarity", from modularity and show that they are significant predictors of reelection success for individual House members, helping to explain why partially-polarized Congresses are less stable. Our results suggest that modularity can serve as an early-warning signal of changing group dynamics, which are reflected only later by changes in formal party labels.


The Etiology of Public Support for the Designated Hitter Rule

Christopher Zorn & Jeff Gill
Quarterly Journal of Political Science, May 2007, Pages 189-203

Since its introduction in 1973, major league baseball's designated hitter (DH) rule has been the subject of continuing controversy. Here, we investigate the political and socio-demographic determinants of public opinion toward the DH rule, using data from a nationwide poll conducted during September 1997. Our findings suggest that it is in fact Democrats, not Republicans, who tend to favor the DH. In addition, we find no effect for respondents' proximity to American or National League teams, though older respondents were consistently more likely to oppose the rule.


Reporting for sale: The market for news coverage

John Gasper
Public Choice, December 2009, Pages 493-508

This paper proposes a formal model of the market for political news. Under reasonable market conditions and when the audience has psychological biases, it may be profitable for outlets to differentiate their coverage. Moreover, the implications of the model speak to a deeper impact of political polarization of the electorate.


Political Climate, Optimism, and Investment Decisions

Yosef Bonaparte, Alok Kumar & Jeremy Page
University of Texas Working Paper, November 2009

This paper shows that people's optimism towards financial markets and the overall economy is dynamically determined by their political affiliation and the current political climate. Republicans (Democrats) are more optimistic and they perceive the markets to be less risky and more under-valued when the Republican (Democratic) party is in power. These optimism shifts are more pronounced among less sophisticated individuals. Political regimes changes are also associated with shifts in overconfidence: Investors are more overconfident when the opposite party is in power. Further, these shifts in optimism, overconfidence, and perceptions of risk and reward influence people's investment decisions. Specifically, investors with a dim view of the domestic economy exhibit strong propensity to invest in foreign stocks. In the domestic setting, they gravitate toward less risky and familiar local stocks. Risk-shifting behavior induced by the political climate affects raw portfolio performance, but risk-adjusted performance remains unchanged. Taken together, these results indicate that the existing political environment is an important determinant of people's investment decisions.

Partisan Divide on War and the Economy: Presidential Approval of G. W. Bush

Gerald Fox
Journal of Conflict Resolution, December 2009, Pages 905-933

This study examines the influence of 9/11, the Iraq War, the economy, and the coalition-of-minorities on presidential approval of G. W. Bush across partisan subgroups and aggregate popularity. The analysis considers the effect of underlying partisan preferences on overall approval. A partisan divide occurs for war and the economy on Bush popularity. The events of 9/11 and the Iraq War affect Democratic opinions of Bush more than Republican opinions, whereas the economy impacts Republicans more than Democrats. An in-party/out-party rally effect occurs. Democrats show stronger rallies than Republicans for 9/11 and the Iraq War, but also faster and deeper popularity decay of the rallies. All economic and war-related effects significantly influence Independents and aggregate Bush popularity. The coalition-of-minorities pattern of declining presidential approval is caused by the 9/11 rally decay effect, the war casualties effect, and the slowing economy during Bush's second term in office.


Partisan gerrymandering and population instability: Completing the redistricting puzzle

Antoine Yoshinaka & Chad Murphy
Political Geography, forthcoming

How can partisan mapmakers enact a partisan gerrymander in the presence of risk-averse co-partisan incumbents who wish to keep most of their constituencies intact? Until now the literature on redistricting has focused on how redistricting affects the geography of partisan support, that is, the underlying partisan balance of electoral districts. We posit that this emphasis on partisanship misses half of the story. Partisan mapmakers have another tool at their disposal: the fostering of population instability that may not affect a district's partisan balance. By examining all redistricting plans enacted in 2001-2002, as well as three case studies, we show that partisan mapmakers strategically foster population instability, which poses problems for incumbents in a way that may not be apparent when looking exclusively at the effects of redistricting on partisanship. Our results show how partisan mapmakers simultaneously achieve two goals: enacting an "optimal gerrymander," which strengthens some opposition-party incumbents, while inducing instability and reducing the personal vote of those same incumbents. We also show that so-called "neutral" redistricting plans are successful in disregarding incumbency. Finally, our results suggest another mechanism that explains why the 2002 congressional elections in the U.S. produced little competition.


Political Affiliation and Perceptions of Trade: Examining Survey Data from the State of Georgia

Roger White & Richard Clark
Contemporary Economic Policy, April 2009, Pages 176-192

We examine the influences of political party affiliation and self-identification as politically conservative, centrist, or liberal on individuals' trade preferences. Majority support for trade is reported for all political classifications, with Republicans found to be 13.7%-15.1% more likely than Democrats and independents to support trade. Similarly, conservatives are 14.8%-21% more likely to support trade than are centrists and liberals; however, distinctions exist between "very conservative" and "somewhat conservative" cohorts.


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