Research

Working Paper
Matthew A. Baum, Bryce Jensen Dietrich, Rebecca Goldstein, and Maya Sen. Working Paper. “Estimating the Effect of Asking About Citizenship on the U.S. Census: Results from a Randomized Controlled Trial”. Publisher's Version

The 2020 U.S. Census will, for the first time since 1950, ask about residents’ citizenship status.The effect of doing so on census completion across different racial/ethnic groups is, however, unknown. Leveraging a survey experiment (n = 9,035 respondents) we are the first to assess the causal effect of this question change. We find that asking about citizenship status significantly increases the percent of questions skipped, with particularly strong effects among Hispanics, and makes respondents less likely to report having members of their household who are of Hispanic ethnicity. Although our study is not designed to address household size effects, when we extrapolate to the general population, our results imply that asking about citizenship will reduce the number of Hispanics reported in the 2010 Census by approximately 4.2 million, or around 8.4 percent of the 2010 Hispanic population.

baum_et_al_citizenship_question.pdf
2021
Roy Perlis, Mauricio Santellana, Katherine Ognyanova, Jon Green, James Druckman, David Lazer, and Matthew Baum. 6/11/2021. “Factors Associated With Self-reported Symptoms of Depression Among Adults With and Without a Previous COVID-19 Diagnosis.” JAMA Network, 4, 6, Pp. 1-4. Publisher's Version perlis_2021_ld_210131_1623176035.22609.pdf
Roy H. Perlis, Katherine Ognyanova, Mauricio Santillana, Matthew A. Baum, David Lazer, James Druckman, and John Della Volpe. 3/12/2021. “Association of Acute Symptoms of COVID-19 and Symptoms of Depression in Adults.” JAMA Network Open, 4, 3, Pp. e213223-e213223. Publisher's Version
After acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a subset of individuals experience persistent symptoms involving mood, sleep, anxiety, and fatigue, which may contribute to markedly elevated rates of major depressive disorder observed in recent epidemiologic studies. In this study, we investigated whether acute coronavirus disease 2019 (COVID-19) symptoms are associated with the probability of subsequent depressive symptoms.
perlis_2021_ld_210038_1614962864.16553-2.pdf
James N. Druckman, Katherine Ognyanova, Matthew A. Baum, David Lazer, Roy H. Perlis, John Della Volpe, Mauricio Santillana, Hanyu Chwe, Alexi Quintana, and Matthew Simonson. 2021. “The role of race, religion, and partisanship in misperceptions about COVID-19.” Group Processes & Intergroup Relations, 24, 4, Pp. 638 - 657.Abstract
Concerns about misperceptions among the public are rampant. Yet, little work explores the correlates of misperceptions in varying contexts – that is, how do factors such as group affiliations, media exposure, and lived experiences correlate with the number of misperceptions people hold? We address these questions by investigating misperceptions about COVID-19, focusing on the role of racial/ethnic, religious, and partisan groups. Using a large survey, we find the number of correct beliefs held by individuals far dwarfs the number of misperceptions. When it comes to misperceptions, we find that minorities, those with high levels of religiosity, and those with strong partisan identities – across parties – hold a substantially greater number of misperceptions than those with contrasting group affiliations. Moreover, we show other variables (e.g., social media usage, number of COVID-19 cases in one’s county) do not have such strong relationships with misperceptions, and the group-level results do not reflect acquiescence to believing any information regardless of its truth value. Our results accentuate the importance of studying group-level misperceptions on other scientific and political issues and developing targeted interventions for these groups.
druckman_et_al._misperceptions_covid-19.pdf
2020
Roy Perlis, Matthew A. Baum, and Katherine Ognyanova. 11/23/2020. “Glaring Omission from Biden's COVID-19 Task Force: Mental Health Expertise.” STAT. Publisher's Version
David Lazer, Jonathan Green, Matthew A. Baum, Alexi Quintana Mathé, Katherine Ognyanova, Adina Gitomer, James N. Druckman, Matthew Simonson, Hanyu Chwe, Roy H. Perlis, Jennifer Lin, and Mauricio Santillana. 10/21/2020. “These nine swing states will see the biggest ‘blue shift’ as ballots are counted after the election.” The Washington Post Monkey Cage. Publisher's Version
Matthew A. Baum, David Lazer, Alexi Quintana, Roy Perlis, Katherine Ognyanova, James N. Druckman, John Della Volpe, and Mauricio Santillana. 7/20/2020. “How a Public Health Crisis Becomes a Public Trust Crisis.” Real Clear Politics. Publisher's Version
Matthew A. Baum. 6/28/2020. “Trump Still Has Approval Ratings Far Higher than George Bush. Here's Why.” Los Angeles Times. Publisher's Version
See also: Op-Eds, Politics
Irene Pasquetto, Matthew A. Baum, Eaman Jahani, and Alla Baranovsky. 5/27/2020. Understanding Misinformation on Mobile Instant Messengers (MIMs) in Developing Countries. Shorenstein Center. Cambridge: Harvard Kennedy School, Shorenstein Center of Media, Politics and Public Policy. Publisher's Version misinfo-on-mims-shorenstein-center-may-2020.pdf
Matthew A. Baum, Dara Kay Cohen, and Susanne Schwarz. 5/6/2020. “(Sex) Crime and Punishment: How Legally Irrelevant Details Influence Crime Reporting and Sanctioning Decisions.” Political Behavior. Publisher's Version
Recent prominent rape cases have raised concerns that the US exhibits a “culture of rape,” wherein victims are often disbelieved and blamed. We present an empirical conceptualization of rape culture, outlining four key features: blaming victims, empathizing with perpetrators, assuming the victims’ consent, and questioning victims’ credibility. In a series of experimental studies, we evaluate the relative impact of different types of rape culture biases on the reporting of rape, and how it is punished. We test how participants’ exposure to legally irrelevant details related to rape culture affects their decision-making. We find that exposure to certain details—relating to the victim’s consent and credibility—significantly decreasesparticipants’ propensities to recommend a rape case be reported to police or to advocate for a severe punishment for the perpetrator. The same biases do not emerge in robbery cases, suggesting that rape is regarded differently from other violent crimes.
sexcrimeandpunishment_polbehavior.pdf
Matthew A. Baum, Katherine Ognyanova, and David Lazer. 4/29/2020. “These Three Governors are Reopening Their States Faster than Their Voters Want: That's What Our Polling Found in Florida, Georgia, and Tennessee.” The Washington Post Monkey Cage. Publisher's Version
Matthew A. Baum. 3/30/2020. “Trump's Coronavirus Approval Rating: Why its Going Up.” Los Angeles Times. Publisher's Version
See also: Op-Eds, Politics
2019
Justin de Benedictis-Kessner, Matthew A. Baum, J. Berinsky, Adam, and Teppei Yamamoto. 11/2019. “Persuading the Enemy: Estimating the Persuasive Effects of Partisan Media with the Preference-Incorporating Choice and Assignment Design.” American Political Science Review, 113, 4, Pp. 902-916. Publisher's Version
Does media choice cause polarization, or merely reflect it? We investigate a critical aspect of this puzzle: how partisan media contribute to attitude polarization among different groups of media consumers. We implement a new experimental design, called the Preference-Incorporating Choice and Assignment (PICA) design, that incorporates both free choice and forced exposure. We estimate jointly the degree of polarization caused by selective exposure and the persuasive effect of partisan media. Our design also enables us to conduct sensitivity analyses accounting for discrepancies between stated preferences and actual choice, a potential source of bias ignored in previous studies using similar designs. We find that partisan media can polarize both its regular consumers and inadvertent audiences who would otherwise not consume it, but ideologically-opposing media potentially also can ameliorate existing polarization between consumers. Taken together, these results deepen our understanding of when and how media polarize individuals. 
mediachoice_apsr_preprint.pdf
Matthew A. Baum, Dannagal G. Young, and Duncan Prettyman. 5/13/2019. “vMOBilize: Gamifying Civic Learning and Political Engagement in a Classroom Context.” Journal of Political Science Education. Publisher's Version

This study presents the results of a quasi-experiment (N= 307) conducted over the course of 10 weeks in Spring of 2016 to assess the effectiveness of a game platform designed to facilitate political engagement, attention, efficacy, knowledge, and participation among college students. Results indicate positive effects of gameplay on several key dimensions of political engagement, including voter registration, virtual political participation (following a candidate on Twitter, liking a candidate on Facebook, and watching debates), and consumption of public affairs information (including National Public Radio, non-NPR political talk radio, and online news aggregator sites). Additionally, gameplay provided significantly greater benefits to students with the lowest rates of political knowledge at baseline. Overall, participants reported high rates of game satisfaction, with 79% of participants reporting being very to somewhat pleased if they were asked to play the game again. These results are discussed in terms of the implications for civics education, pedagogy, and political engagement among young people.

vmobilize_jpe_preprint.pdf
Justin de Benedictis-Kessner, Matthew A. Baum, and Adam J. Berinsky. 5/9/2019. “Polarization and Media Usage: Disentangling Causality.” In Oxford Handbook of Electoral Persuasion. New York: Oxford University Press. Publisher's Version
This chapter examines the literature concerning media choice and partisan polarization.  The past few decades have seen enormous growth in the number of television and internet news sources, giving consumers dramatically increased choices.  Previous research has suggested two distinct links between media choice and partisan polarization: partisan media as a reflectionof polarization, as partisans self-select into media that conforms with their preexisting views, or as a causeof polarization, when outlets present one-sided stories that persuade people to adopt more extreme views.  This chapter discusses how the literature in these two research traditions has diverged, as well as more recent research attempting to bridge this divide.  Using novel methods, these studies have drawn together both self-selection and causal research designs to provide a more complete picture of media choice effects, and expanded the literature to more recent mediums, including the internet and social media.
polarizationcausality180806.pdf
Dean Knox, Teppei Yamamoto, Matthew A. Baum, and Adam Berinsky. 4/30/2019. “Design, Identification, and Sensitivity Analysis for Patient Preference Trials.” Journal of the American Statistical Association, 114, 528, Pp. 1532-1546. Publisher's Version

Social and medical scientists are often concerned that the external validity of experimental results may be compromised because of heterogeneous treatment effects. If a treatment has different effects on those who would choose to take it and those who would not, the average treatment effect estimated in a standard randomized controlled trial (RCT) may give a misleading picture of its impact outside of the study sample. Patient preference trials (PPTs), where participants’ preferences over treatment options are incorporated in the study design, provide a possible solution. In this paper, we provide a systematic analysis of PPTs based on the potential outcomes framework of causal inference. We propose a general design for PPTs with multi-valued treatments, where participants state their pre- ferred treatments and are then randomized into either a standard RCT or a self-selection condition. We derive nonparametric sharp bounds on the average causal effects among each choice-based sub- population of participants under the proposed design. We also propose a sensitivity analysis for the violation of the key ignorability assumption sufficient for identifying the target causal quantity. The proposed design and methodology are illustrated with an original study of partisan news media and its behavioral impact.

mediachoicemethod_final.pdf
Matthew Barreto, Chris Warshaw, Matthew A. Baum, Bryce J. Dietrich, Rebecca Goldstein, and Maya Sen. 4/22/2019. “New Research Shows Just How Badly a Citizenship Question Would Hurt the 2020 Census.” Washington Post Monkey Cage. Publisher's Version
Matthew A. Baum and Yuri M. Zhukov. 4/9/2019. “Media Ownership and News Coverage of International Conflict.” Political Communication, 36, 1, Pp. 36-63. Publisher's Version
How do differences in ownership of media enterprises shape news coverage of international conflict? We examine this relationship using a new dataset of 591,532 articles on US-led multinational military operations in Libya, Iraq, Afghanistan and Kosovo, published by 2,505 newspapers in 116 countries. We find that ownership chains exert a homogenizing effect on the content of newspapers’ coverage of foreign policy, resulting in coverage across co-owned papers that is more similar in scope (what they cover), focus (how much “hard” relative to “soft” news they offer), and diversity (the breadth of topics they include in their coverage of a given issue) relative to coverage across papers that are not co-owned. However, we also find that competitive market pressures can mitigate these homogenizing effects, and incentivize co-owned outlets to differentiate their coverage. Restrictions on press freedom have the opposite impact, increasing the similarity of coverage within ownership chains.
bz_ownership_final.pdf
Matthew A. Baum and Philip B. K. Potter. 4/2019. “Media, Public Opinion, and Foreign Policy in the Age of Trump.” Journal of Politics, 81, 2, Pp. 747-756. Publisher's Version

Democratic publics have always struggled to constrain their elected leaders’ foreign policy actions. By its nature, foreign policy creates information asymmetries that disadvantage citizens in favor of leaders. But has this disadvantage deepened with the advent of the Internet and the resulting fundamental changes in the media and politics? We argue that it has. The current information and political environments erode constraint by inclining constituents to reflexively and durably back “their” leaders and disapprove of opposition. These changes make it harder for citizens to informationally “catch up” with and constrain leaders because views that contradict citizens’ beliefs are less likely to break through when media are fragmented and siloed. These changes have important implications for theories concerning the democratic peace, audience costs, rally effects, and diversionary war. They may also contribute to instability in foreign policy by contributing to sudden and destabilizing changes in public opinion that undercut commitments abroad.

baum_potter_jop_preprint.pdf
Matthew A. Baum and Dannagal G. Young. 2019. “The “Daily Them": Hybridity, Political Polarization and Presidential Leadership in a Digital Media Age.” In New Directions in Public Opinion Research, Third Edition. Routledge. Publisher's Version baumyoung_dailythem_proofs.pdf

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