Dylan W. Groves

Assistant Professor of Government and Law, Lafayette College

Published and Forthcoming

The effect of radio dramas on willingness to report intimate partner violence: evidence from a survey experiment in Tanzania
Kate SantaMaria, Noela Ringo, Kasim Abdallah, Dylan W. Groves, Brenda Nyambo
Frontiers: Health Communication (2026)
abstract

Intimate partner violence remains widespread partly because survivors and witnesses are reluctant to report incidents to authorities. This study examined whether narrative media messages could increase reporting willingness in rural Tanzania through an experiment with 1,009 respondents across 15 villages. Participants heard either a 1.5-minute radio drama or received no treatment. Results showed fewer than 10% of control respondents recommended police reporting. Those exposed to the drama were 8.9 percentage points more likely to recommend police reporting (p < 0.001). However, the intervention did not improve outcomes regarding village chairperson reporting or witness reporting. The authors concluded that narrative dramas can influence behavioral intentions central to their narrative, but with limited spillover to related attitudes or behaviors.

The persuasive effects of narrative entertainment: a meta-analysis of recent experiments
Bardia Rahmani, Dylan W. Groves, Beatrice Montano, Donald P. Green
Behavioral Science and Public Policy (2025)
abstract

Is narrative entertainment simply a form of recreation, or does it have meaningful effects on public opinion? Building on prior reviews, we present a meta-analysis of 377 findings from 77 experiments evaluating the persuasive effects of narrative radio, television, and film, including a growing body of work from low- and middle-income countries. Our sample includes both entertainment-first narratives---popular media created primarily to entertain but which may incidentally shape audiences' attitudes, beliefs, and behaviors---and education-first narratives designed by policymakers to inform, persuade, or motivate public action. Using a hierarchical-effects model, we assess narrative media's influence across a wide range of settings and issue domains. The results suggest that narrative entertainment is quite influential, with sizable persuasive effects that remain apparent weeks after initial exposure. A smaller literature reports head-to-head tests of the relative effectiveness of narrative versus non-narrative messages; although inconclusive, the evidence suggests that narratives may be only slightly more persuasive than non-narrative messages. If true, this finding would imply that the main advantage of narratives may be their ability to attract and engage large and diverse audiences. We conclude by calling attention to gaps in the literature and proposing avenues for further research.

Media capture in Africa: a case study in Tanzania
Dylan W. Groves, Anya Schiffrin, Marco Kitundu, Francis Nyonzo
Routledge Handbook of Political Corruption (Forthcoming)
abstract

This chapter defines media capture as a situation in which the news media are controlled either directly by governments or by vested interests networked with politics. The authors developed a hand-coded dataset on media ownership in Tanzania since 1990 and conducted surveys of more than 300 journalists plus 20 in-depth interviews. Their research documented the extent to which media capture is used to undermine coverage of corruption scandals in Tanzania and other Sub-Saharan African countries.

Better together: the perceived impact of the Pandora Papers on journalism and journalists
Anya Schiffrin, Dylan W. Groves, Audrey Hatfield, Lindsay Green-Barber
Information, Communication, and Society (2024)
abstract

This paper analyzed how journalists and media organizations perceived the impact of the International Consortium of Investigative Journalists' Pandora Papers collaboration. The study surveyed more than 55 participating media outlets. Results showed journalists and media organizations perceive that collaborative investigations generate substantial positive internal returns for participating organizations, such as professional development and new media partnerships, although we observe no perceived impact on revenue. The authors proposed organizing impact studies using a multi-dimensional taxonomy.

The effects of independent local radio on Tanzanian public opinion: evidence from a planned natural experiment
Donald P. Green, Dylan W. Groves, Constantine Manda, Beatrice Montano, Bardia Rahmani
Journal of Politics (2023)
abstract

This natural experiment exploited an abrupt increase in transmission range for an independent Tanzanian radio station. Baseline surveys found treated and untreated villages were similar before transmission changes in 2018. Endline surveys in 2020 showed treated respondents were substantially more likely to listen to the station, and their levels of political interest and knowledge about domestic politics were significantly higher than their counterparts in villages where the signal could not reach. However, attitude change on a range of gender issues was inconsistent across measures.

Perspective taking through partisan eyes: cross-national empathy, partisanship, and attitudes towards international cooperation
Don Casler, Dylan W. Groves
Journal of Politics (2023)
abstract

This study examined whether cross-national empathy influences support for international cooperation across three survey waves with 6,292 respondents. The researchers found that cues to step into the perspective of other states modestly increase aggregate support for international cooperation. But this effect is concentrated entirely among those with weak partisan attachments, regardless of the issue area (climate change or nuclear nonproliferation) and potential partner country (China or India).

Understanding journalism impact: a multidimensional taxonomy for professional, organizational, and societal change
Anya Schiffrin, Andre Correa-Almeida, Lindsay Green-Barber, Adelina Yankova, Dylan W. Groves
Journal of Applied Journalism and Media Studies (2023)
abstract

This paper proposes a multi-faceted metric which future researchers, journalists and news agencies will be able to use when analyzing media impact. The authors drew on multiple disciplines to address how researchers should measure investigative journalism's effects on a range of social, political, and economic outcomes.

Seeing cattle like a state: sedentist assumptions of the Namibian Livestock Identification and Traceability System
Max Mauerman, Venoo Tjiseua, Dylan W. Groves
Nomadic Peoples (2023)
abstract

This paper argues that livestock identification and traceability systems are suffused with sedentist assumptions that are at odds with the livestock management practices of pastoralist communities. Through qualitative interviews and field experience, the authors reviewed sedentist assumptions in the Namibian system and described how pastoralists in north-western Namibia perceive that NamLITS has affected their economic, social and political lives, as well as the strategies that pastoralists use to comply and circumvent NamLITS.

Community-based rangeland management in Namibia improves resource governance but not environmental and economic outcomes
D. Layne Coppock, Lucas Crowley, Susan L. Durham, Dylan W. Groves, Julian C. Jamison, Dean Karlan, Brien E. Norton, R. Douglas Ramsey
Nature — Communications Earth & Environment (2022)
abstract

This randomized evaluation studied a four-year comprehensive program supporting community-based rangeland and cattle management in Namibia. Results showed the program led to persistent and large improvements for eight of thirteen indices of social and behavioral outcomes. Effects on rangeland health, cattle productivity and household economics, however, were either negative or nil. The authors concluded that positive impacts on community resource management may have been offset by communities' inability to control grazing by non-participating herds.

A radio drama's effects on attitudes toward early and forced marriage: results from a field experiment in rural Tanzania
Donald P. Green, Dylan W. Groves, Constantine Manda, Beatrice Montano, Bardia Rahmani
Comparative Political Studies (2022)
abstract

A two-hour radio drama was presented to Tanzanian villagers in a placebo-controlled village-level randomized experiment. The baseline sample included 1,200 villagers, with 83% attending the presentation. The radio drama produced sizable and statistically significant effects on attitudes and perceived norms concerning forced marriage, which was the focus of the radio drama, as well as more general attitudes about gender equality. Fifteen months later, treatment effects diminished, but we continue to see evidence of EFM-related attitude change.

A radio drama's effects on HIV attitudes and policy priorities: a field experiment in Tanzania
Donald P. Green, Dylan W. Groves, Constantine Manda
Health Education and Behavior (2021)
abstract

This study presented a condensed 2-hour Swahili radio drama to rural Tanzanians in a placebo-controlled village-level experiment. A random sample of 1,200 participants completed baseline interviews, with 83% attending the screening and 95% responding to a 2-week follow-up. In addition to increasing listeners' knowledge and support for disclosure of HIV status, the radio drama produced sizable and statistically significant effects on listeners' preference for hypothetical candidates promising improved HIV/AIDS treatment.

The mismeasurement of cattle ownership in Namibia's Northern Communal Areas
Dylan W. Groves, Venoo Tjiseua
Nomadic Peoples (2020)
abstract

The authors argue that the standard approach to measuring livestock ownership in pastoralist communities relies on an assumption of uniformity that does not reflect the diverse concepts of ownership held by pastoralists themselves. Drawing on field experience, they demonstrate how the standard approach to measuring cattle ownership undermines accurate estimates of livestock wealth, off-take and inequality, and obfuscates pastoralists' strategies for turning ecological variability to their advantage.

The influence of two levels of debushing in Namibia's thornbush savanna on overall soil fertility, measured through bioassays
Ibo Zimmermann, Mattis Nghikembua, D Shipingana, Dylan W. Groves, T Aron, L Marker
Namibian Journal of the Environment (2017)
abstract

This study examined soil fertility effects of different debushing intensities at the Cheetah Conservation Fund farm in Namibia. Researchers collected soil from 27 sites representing uncleared, partially cleared, and totally cleared land at varying times since debushing. Results showed seedling emergence and height at five weeks for both species were greatest in uncleared soil and lowest in totally cleared soil, indicating the loss of soil fertility as debushing intensifies. There was no evidence of restoration of soil fertility, even 13 years after debushing.

Working Papers

The persuasive power of Africa's High Courts: evidence from Tanzania
Salma Emmanuel, Dylan W. Groves, Beatrice Montano, Constantine Manda, Donald P. Green, Bardia Rahmani
Revise and Resubmit
abstract

This study evaluated whether Tanzania's constitutional court ruling declaring marriage laws for girls under 18 unconstitutional shaped social attitudes. The researchers randomly assigned 1,950 rural respondents to hear a radio report about the ruling or a control condition. Respondents who heard the report were 8 percentage points more likely to reject all forms of early marriage and 5.4 percentage points more likely to say they would report early marriage to authorities. However, the report did not influence perceptions of community norms or willingness to speak out against early marriage.

The long-term effects of a radio drama on HIV attitudes and policy priorities
Dylan W. Groves, Alphincina Kigaigai, Beatrice Montano, Savannah Nivin, Bardia Rahmani, Donald P. Green
Under Review
abstract

This cluster-randomized field experiment in rural Tanzania assessed long-term and spillover effects of a Swahili radio drama addressing HIV disclosure and treatment. The researchers randomly assigned 30 villages to treatment or control conditions. Eighteen months after screening, we observe persistent effects on primary respondents' HIV knowledge, disclosure willingness, and policy prioritization. Disclosure attitudes transmitted to partners and children but not friends, suggesting spillover occurs through household relationships rather than broader networks.

Climate and cooperation: evidence from Namibia
Garrett Adler, Dylan W. Groves
Under Review
abstract

This study paired a severe and spatially varying drought with behavioral games and surveys from approximately 1,000 livestock managers in 123 grazing areas across northern Namibia. The researchers tested whether play in public goods games differs between more and less severe drought conditions and explored how observed measures of collective behavior, including participation in water resource management and community grazing institutions, vary with the experience of drought. Results provided evidence that severe climatic shocks tend not to affect or to increase individuals' propensity to act pro-socially and collectively.

Journalism and blame attribution in hegemonic party regimes: evidence from Tanzania
Benjamin Risley, Dylan W. Groves, Zakayo Zakaria
Under Review
abstract

This pre-registered lab-in-the-field experiment with 1,009 respondents across 15 rural villages evaluated how journalists' blame attribution affects political accountability. Local journalists investigated water service delivery failures and produced two identical reports except one blamed the Member of Parliament while the other blamed the rural water bureaucracy. Relative to the report blaming the bureaucracy, the report blaming the MP made respondents 27 percentage points more likely to hold the MP primarily responsible for water services and 8 percentage points less likely to say they would vote for the MP in the next election.

Information or motivation? How watchdog journalism can promote government responsiveness in Tanzania
Dylan W. Groves
abstract

This study evaluated two mechanisms through which journalism influences government responsiveness: informing officials about constituent preferences and motivating officials through public exposure threat. Surveys covered 4,200 citizens and 340 leaders across 109 Tanzanian villages. The study examined whether leaders understand, share, and respond to the policy preferences of their constituents and tested two overlapping treatments designed to capture each mechanism. Results indicated strong evidence for the role of motivation, and no evidence for complementarity between the two mechanisms. The effect is concentrated among elected officials rather than bureaucrats.

A radio drama's effects on environmental protection: experimental evidence from Tanzania
Bardia Rahmani, Dylan W. Groves, Beatrice Montano, Donald P. Green
abstract

This experiment assigned 1,360 respondents from 34 villages to attend screenings of one of two radio dramas. The treatment drama depicts a corrupt bargain between a business developer and a public official to sell off the natural resources of a fishing village; the hero of the story rallies villagers to reject the deal in favor of environmental preservation. Results showed treatment participants became more knowledgeable about climate change, more likely to cite environmental protection as a political priority, and substantially more supportive of pro-environmental policies and candidates. However, no effects were found on other outcomes, such as respondents' proclivity to engage in or punish illegal logging.

Governments respond to watchdog journalism: evidence from a field experiment in Tanzania
Dylan W. Groves
abstract

This national-scale randomized controlled trial evaluated investigative journalism's influence on government responsiveness. The researcher collaborated with 15 regional radio stations to identify 206 communities experiencing service delivery problems. Half were randomly assigned to treatment; journalists investigated problems and broadcast findings on regional radio. Seven months after the reports were broadcast, independent auditors evaluated the service delivery problem in all 206 communities. Treatment communities received higher audit scores on average (coefficient = 0.25 standard deviations, randomization inference p-value = 0.033), amounting to one road or water point repair in every four treated communities.

Religious elite messaging and women's political participation
Bardia Rahmani, Dylan W. Groves, Beatrice Montano, Francis Ngatigwa, Donald Green
abstract

This survey experiment in northeastern Tanzania estimated whether a pro-women's political participation message from a progressive religious leader affects behavioral intentions, attitudes, and norms. Across two studies, the progressive religious elite's message makes villagers more likely on average to say they would encourage their daughter or niece to run for political office. These effects on behavioral intentions persisted a month later. The researchers found suggestive evidence that the children of respondents who received the progressive elite's message became more interested in running for political office.

The effect of climate change news on public opinion about the environment: evidence from a lab-in-the-field experiment in Tanzania
Alexander Brown, Salma Emmanuel, Beatrice Montano, Bardia Rahmani, Donald P. Green, Dylan W. Groves
abstract

This experiment tested how climate change news stories shaped environmental attitudes. Respondents were randomly assigned to hear one of two radio news reports or a control condition. Both treatments increased understanding of climate change's human causes and negative consequences, as well as support for local environmental protection behaviors and policies. However, the clips did not affect attitudes, perceived norms, or intentions to engage in climate change mitigation. The report emphasizing international causes moderately increased awareness of those causes but did not influence environmental attitudes or behaviors.

Narrative entertainment shapes policy priorities: evidence from four field experiments in Tanzania
Salma Emmanuel, Donald P. Green, Dylan W. Groves, Constantine Manda, Beatrice Montano, Bardia Rahmani
abstract

This series examined four radio dramas' impacts on audience policy prioritization regarding environmental protection, gender-based violence, early and forced marriage, and HIV treatment access. The researchers measured priorities through a conjoint experiment assessing voting preferences and a card-sorting exercise. Three of the four dramas significantly increased listeners' preference for hypothetical candidates promising to address the issue featured in the drama, and all four dramas elevated the perception that the issue represents a top priority for the community. Pooling across studies with 4,464 participants, the average treatment effects of narrative messages on voting and prioritization are substantial and statistically significant.

Works in Progress

A national-scale field experiment of radio messages and public health services in Tanzania
Dylan W. Groves, Salma Emmanuel, Constantine Manda, John Marshall
A national-scale field experiment on radio messaging and family planning in Nigeria
Dylan W. Groves, John Marshall, Mahesh Karra, Nneka Osalador
A national-scale field experiment of digital feedback to improve health services
Dylan W. Groves, Robbie Dulin, Pascaline Dupas, Alphoncina Kigaigai, John Marshall
Can radio dramas reduce intimate partner violence: experimental evidence from Rwanda
Dylan W. Groves, Aline Umubyeyi, Horace Gninafon, Donald P. Green
Leveraging religious leaders to counter human trafficking in rural Tanzania
Dylan W. Groves, Salma Emmanuel, Beatrice Montano
Bias and precision in measurement of livestock weight
Dylan W. Groves, Andrew Dillon, Alexander Fertig, Dean Karlan

Policy Papers

Journalism for development: the role of journalism promoting democracy and political accountability and sustainable development
Joseph E. Stiglitz, Anya Schiffrin, Dylan W. Groves
Improving rangeland and livestock management in Namibia
D. Layne Coppock, Lucas Crowley, Susan L. Durham, Dylan W. Groves, Julian C. Jamison, Dean Karlan, Brien E. Norton, R. Douglas Ramsey
A radio drama's effects on gender based violence: experimental evidence from Tanzania
Beatrice Montano, Salma Emmanuel, Donald P. Green, Dylan W. Groves, Bardia Rahmani
abstract

This placebo-controlled village-level randomized experiment examined whether edutainment about gender-based violence affects awareness, policy priorities, and preferred responses. A random sample of 1,250 villagers completed baseline interviews and attended one of two randomly assigned radio drama screenings, with follow-up interviews one month later. The 90-minute radio drama that focuses on GBV both raises awareness about the risks women face in their daily lives and increases the importance that audiences accord to sexual violence as a community problem. The authors concluded that narrative mass media offers an effective and scalable means for spurring collective action responses to threats to women's safety in public spaces.