Using both survey- and platform-based measures of support, we study how polarization manifests for 4,313 of President Donald Trump’s tweets since he was inaugurated in 2017. We find high levels of polarization in response to Trump’s tweets. However, after controlling for mean differences, we surprisingly find a high degree of agreement across partisan lines across both survey and platform-based measures. This suggests that Republicans and Democrats, while disagreeing on an absolute level, tend to agree on the relative quality of Trump’s tweets. We assess potential reasons for this, for example, by studying how support changes in response to tweets containing positive versus negative language.We also explore how Democrats and Republicans respond to tweets containing insults of individuals with particular socio-demographics, finding that Republican support decreases when Republicans, relative to Democrats, are insulted, and Democrats respond negatively to insults of women and members of the media.

Drawn from presentations by
Yochai Benkler (Harvard), Adam Berinsky (MIT), Helen Boaden (BBC), Katherine Brown (Council on Foreign Relations), Kelly Greenhill (Tufts and Harvard), David Lazer (Northeastern), Filippo Menczer (Indiana), Miriam Metzger (UC Santa Barbara), Brendan Nyhan (Dartmouth), Eli Pariser (UpWorthy), Gordon Pennycook (Yale), Lori Robertson (FactCheck.org), David Rothschild (Microsoft Research), Michael Schudson (Columbia), Adam Sharp (formerly Twitter), Steven Sloman (Brown), Cass Sunstein (Harvard), Emily Thorson (Boston College), and Duncan Watts (Microsoft Research).

Executive Summary

Recent shifts in the media ecosystem raise new concerns about the vulnerability of democratic societies to fake news and the public’s limited ability to contain it. Fake news as a form of misinformation benefits from the fast pace that information travels in today’s media ecosystem, in particular across social media platforms. An abundance of information sources online leads individuals to rely heavily on heuristics and social cues in order to determine the credibility of information and to shape their beliefs, which are in turn extremely difficult to correct or change. The relatively small, but constantly changing, number of sources that produce misinformation on social media offers both a challenge for real-time detection algorithms and a promise for more targeted socio-technical interventions.

Why do some democracies reflect their citizens' foreign policy preferences better than others? What roles do the media, political parties, and the electoral system play in a democracy's decision to join or avoid a war? War and Democratic Constraint shows that the key to how a government determines foreign policy rests on the transmission and availability of information. Citizens successfully hold their democratic governments accountable and a distinctive foreign policy emerges when two vital institutions—a diverse and independent political opposition and a robust media—are present to make timely information accessible.

Matthew Baum and Philip Potter demonstrate that there must first be a politically potent opposition that can blow the whistle when a leader missteps. This counteracts leaders' incentives to obscure and misrepresent. Second, healthy media institutions must be in place and widely accessible in order to relay information from whistle-blowers to the public. Baum and Potter explore this communication mechanism during three different phases of international conflicts: when states initiate wars, when they respond to challenges from other states, or when they join preexisting groups of actors engaged in conflicts.

Examining recent wars, including those in Afghanistan and Iraq, War and Democratic Constraint links domestic politics and mass media to international relations in a brand-new way.

Scholars have long recognized that public support for presidential uses of military force depends critically on elite support. Similarly, scholars have argued that the media “index” their coverage of foreign policy to reflect the responses of partisan (particularly congressional) elites. We argue that journalists' choices also play an important role by systematically (and predictably) skewing the elite rhetoric presented to the public. In particular, we argue that criticism of the president by his own party is disproportionately likely to be broadcast -- particularly in unified government -- and that such criticism should be exceptionally persuasive to citizens. To separate the media’s independent effect from that of the actual tenor of elite discourse, as presented in the news, we investigate all interviews with members of Congress on network television Sunday morning political interview shows between 1980 and 2003. We then determined which comments were selected for inclusion on the evening news and compare the characteristics of such comments to those that were not selected, both during periods immediately following major U.S. uses of military force and during “normal” periods. We find that the evening news presents a biased sample of elite rhetoric, heavily over-representing criticism of the president by his own party, while under-representing supportive rhetoric. Our findings indicate that future studies of public opinion and U.S. foreign policy must take into account the intervening role of journalists, who function as strategic, self-interested gatekeepers of public information regarding foreign policy events.

You can download a pdf version of the paper, here.

Research has shown that human beings are biased information processors. This study investigates an important potential example of biased information processing: when ex ante assessments of a media outlet’s ideological orientation “cause” individual’s to perceive bias.  We conduct an experiment in which subjects evaluated the content of a news report about the 2004 presidential election identified as originating from CNN, FOX or a fictional TV station.  Our results suggest that in an increasingly fragmented media marketplace, individuals not only distinguish between media outlets but, more importantly, outlet “brand names,” and the reputations they carry, function as heuristics, heavily influencing perceptions of bias in content. Individuals sometimes “create” bias, even where none exists. This suggests that assessments of media content operate on a more nuanced level than has been captured in previous research.

You can download this paper, in pdf format, along with a replication dataset here.

Democracy requires that citizens’ opinions play some role in shaping policy outcomes, including in foreign policy. Yet, while the literature on public opinion and foreign policy has made great progress over the past several decades, scholars have reached no consensus concerning what the public thinks, or thinks about, with respect to foreign policy, how it comes to hold those opinions, or whether those opinion do or should influence foreign policy. In this chapter, we first review the extensive gains in scholarly knowledge in the area of public opinion and foreign policy over the past several decades (with a particular emphasis on relatively recent work). We then suggest a framework, based on the concept of market equilibrium, aimed at synthesizing the various disparate research programs that together constitute the literature on public opinion and foreign policy. To do so, we incorporate a third strategic actor, the mass media, which we believe play a critical role alongside citizens and elites in shaping public attitudes about, and influence upon, foreign policy. Our goal is to clarify the multifaceted relationships between these actors and foreign policy outcomes.

You can download the current version of this chapter, in pdf format, here.

Research has shown that messages of intra-party harmony tend to be ignored by the news media, while internal disputes, especially within the governing party, generally receive prominent coverage. We examine how messages of party conflict and cooperation affect public opinion regarding national security, as well as whether and how the reputations of media outlets matter. We develop a typology of partisan messages in the news, determining their likely effects based on the characteristics of the speaker, listener, news outlet, and message content. We hypothesize that criticism of the president by his fellow partisan elites should be exceptionally damaging (especially on a “conservative” media outlet), while opposition party praise of the president should be the most helpful (especially on a “liberal” outlet). We test our hypotheses through an experiment and a national survey on attitudes regarding the Iraq War. The results show that credible communication (i.e., “costly” rhetoric harmful to a party) is more influential than “cheap talk” in moving public opinion. Ironically, news media outlets perceived as ideologically “hostile” can actually enhance the credibility of certain messages relative to “friendly” news sources.

You can download this paper, in pdf format, here.

Since the 1980s, the mass media have changed the way they cover major political stories, like foreign policy crises, and, as a consequence, in what the public learns and believes about these events. More media outlets cover major political events than in the past, including the entertainment-oriented soft news media. When they do cover a political story, soft news shows do so differently than the traditional news media, focusing more on “human drama,” and especially the character and motivations of decision-makers, as well as individual stories of heroism or tragedy, and less on the political or strategic context, or substance, of policy debates. Consequently, many Americans who previously ignored politics now attend to some information about major political events, like wars, via the soft news media. Less politically engaged Americans who learn about major events from the soft news media are more suspicious of the motives of political leaders and less supportive of their policies than their non-soft-news-consuming, or more-politically-engaged counterparts.

Soft news, in turn, is gaining popularity around the world. Consequently, these changes have important implications for democratic politics both in the United States and abroad. Most importantly, a large number of relatively apolitical, and hence particularly persuadable, potential voters are now tuning in to politics via soft news outlets. This gives politicians an incentive to develop strategies for reaching out to soft news consumers. Such individuals care less about the nuances of policy and more about the personality of leaders and any sensational human drama that a policy, like a war, entails. Soft news consumers care less about geopolitics than about body bags. Politicians who want their votes are therefore likely to emphasize body bags rather than geopolitics. In short, the “new” media environment is changing both the style and substance of politics in democracies.

You can download this article, in pdf format, here.

Do the news media provide voters with sufficient information to function as competent democratic citizens? Many have answered “no,” citing as evidence the proliferation of entertainment-oriented “soft news.” Yet, public affairsoriented “hard” news is often unappealing to politically inattentive individuals. We argue that news “quality” depends upon how well it enables citizens to determine which candidate best fits their own preferences. In this regard, for politically inattentive citizens, we argue that soft news is more efficient than traditional hard news. Drawing on the logic of low-information rationality, we derive a series of hypotheses, which we test using the 2000 National Election Study.We find that politically inattentive individuals who consumed daytime talk shows (a popular form of soft news) were more likely than their nonconsuming, inattentive counterparts to vote for the candidate who best represented their self-described preferences. This suggests soft news can facilitate voting “competence” among at least some citizens.

Slate.com editor-at-large Jack Shafer wrote an article about this study, You can find it here. "UCLA Today" also did a feature story on the study, which you can find here.

You can download this paper, in pdf format, here.

A supplemental appendix for this paper, including expert survey questionnaire, NES variable definitions and coding, additional discussion of several concepts addressed in the paper, as well as a variety of robustness, reliability and validity tests, is available, in pdf format, here.

In an effort to show themselves as “regular guys,” the 2000 presidential election found presidential aspirants commiserating with Oprah Winfrey, Rosie O'Donnell, Queen Latifah and Regis Philbin, trading one-liners with Jay Leno and David Letterman, discussing rap music with MTV's youthful viewers and even courting the kid (or perhaps parent) vote on Nickelodeon. This study is a preliminary assessment of the impact of entertainment-oriented talk show coverage of presidential politics, using the 2000 election as a case study.   I consider why entertainment-oriented TV talk shows might choose to cover presidential politics, why candidates choose to appear on talk shows, and who is likely to be the primary audience for such coverage. This discussion yields a series of hypotheses concerning the effects of talk show coverage of presidential politics on public views of the candidates and the campaign.   I test my hypotheses through a content analysis of campaign coverage by entertainment-oriented talk shows, traditional political talk shows, and national news campaign coverage, as well as through a series of statistical analyses employing the 2000 NES. I find that talk show coverage of presidential politics does indeed influence voter attitudes. In particular, net of partisan preferences and a variety of other demographic and political factors, voters who rely primarily on entertainment-oriented TV talk shows as a source of campaign information are more likely to find the opposition candidate “likeable,” as well as to cross party lines and vote for him, relative to their more politically aware counterparts who pay closer attention to traditional news outlets.

This article is available for download from JSTOR here.

You can download a zip archive containing the 2000 NES variable definitions and re-coding, as well as the content analysis data and coding form, from this article here.