Mapping the Issue Arena of Plastic Soup: Applying the Network Agenda-Setting (NAS) Model in Big-Data Research

by Louelle Pesurnaij
Thesis supervisor: dr. Iina Hellsten

Social media platforms such as Twitter are becoming more important for communication between stakeholders (Hellsten & Wonneberger, 2019). Especially with regard to environmental issues, Twitter has proven useful for communication among all parties involved, because information is disseminated rapidly and Twitter allows actors (e.g., individuals, organizations) to interact and discuss the issues (Getchell & Sellnow, 2016). One important, global issue that has gained public concern in the past decades and involves many stakeholders is the so-called Plastic Soup-issue (i.e. plastic marine pollution; Dauvergne, 2018).

Communication about issues such as Plastic Soup generally take place on so-called “issue arenas”, (social media) platforms where societal and environmental issues are discussed by and among stakeholders (Luoma-aho & Vos, 2010). The issue arena approach implies that organization-centered views of stakeholders are becoming outdated and highlights the importance that with environmental issues such as Plastic Soup stakeholders are viewed from an issue-centered perspective. The issue arena perspective hence states that not the immediate stakeholders of organizations (e.g., corporations, NGOs, the media) matter but rather the stakeholders surrounding specific (environmental) issues.

The dissemination of information regarding an environmental issue such as Plastic Soup starts, according to agenda-setting theory (McCombs & Shaw, 1972), at the media who put certain issues on the public or political agenda which are deemed worthy of discussion (Carroll & McCombs, 2003). Contradictory to the issue arena perspective (Luoma-aho & Vos, 2010), which proposes that issues arise as they are discussed by and among stakeholders, traditional agenda-setting research (McCombs & Shaw, 1972) assumes that media have the ability to raise awareness for specific issues, put these issues on the public agenda and initiate public debate. The media hence dictates what the public speaks about and how they speak about it.

In this paper, the agenda-setting role of specific stakeholders in the Plastic Soup-issue arena were examined by analyzing large datasets on Twitter by using innovative, digital research methods, such as automated content analyses (e.g. big data analytics) and machine learning (i.e. semantic network analysis). More specifically, this study tested an emerging agenda-setting theory: the Network Agenda-Setting (NAS) model (e.g., Guo, 2012). Traditional agenda-setting research asserts that media have the ability to influence the salience of topics and topic attributes on the public agenda. The NAS model extends this view by asserting that topics and attributes are not just transferred as individual elements but transferred as interconnected bundles from the media agenda to the public agenda. The more often media link topics and/or attributes in news coverage, the more likely it is that the public will also link those topics and/or attributes (Vu, Guo, & McCombs, 2014).

The present study sought to apply the NAS model in a corporate communication context and showcase the model its potential contribution to theory in the field of sustainability/CSR. This study thereby aimed to expand the NAS model by examining the network attribute agendas of the media, non-governmental organizations (NGOs) and the public from an issue arena perspective. While agenda-setting theory (e.g., Carroll & McCombs, 2003) is media-centered, the issue arena approach (Luoma-aho & Vos, 2010) asserts that issue arenas (i.e., platforms where stakeholders discuss issues) are not media- nor NGO-centered, but issue-centered. In this study, it was examined to what extent attributes of the Plastic Soup issue (e.g., fighting plastic pollution, the origin of plastic pollution, specific (plastic) products, stakeholder involvement) are transferred from the attribute networks of the media and NGOs’ agendas to the public agenda on Twitter.

In total, all tweets of Dutch news media (n=611), NGOs (n=986) and the public (n=31.290) about Plastic Soup between January 2018 and December 2018 were examined. In order to show to what extent the attributes on the network agendas of the media and NGOs are transferred the public network agendas, Quadratic Assignment Procedure (QAP) correlation and regression tests were conducted to compare the three network agendas.

Empirically, this study found that both media and NGOs have the ability to set the public agenda and dictate how the public links attributes of Plastic Soup. For example, the attributes “Stakeholder involvement” and “Fighting plastic pollution” were the most associated attributes in tweets by both NGOs and the public. These attributes co-occurred in 36,0% of (n=355) of all tweets by NGOs (n=986) and were linked in 28.2% (n= 9.265) of all tweets by the public (n=32.887).

Additionally, the results of this study suggest that NGOs have a stronger agenda setting power than news media. The network attribute agenda of NGOs is able to predict 95.1% of the differences in the public network attribute agenda and the network attribute agenda of the media is only able to predict 51.2% of the differences in the public network attribute agenda. These findings support the results of earlier research on the NAS model (e.g., Vu et al., 2014) that media can influence how the public links different attributes and, furthermore, this study expanded the scope of previous NAS research by examining the agenda-setting power of both media and NGOs.
This study offers insights into the interplay between the news media, NGOs and the public and clarifies the agenda-setting phenomenon.

The NAS model provides insights into how the media/NGOs link different attributes of Plastic Soup and in turn influence how the public links those different attributes, which is relevant for both the academic literature and the practice of corporate communications, PR and journalism, analysing how the media/NGOs link different attributes of Plastic Soup and in turn influence how the public links those different attributes. The findings of this study can help practitioners to effectively design campaign messages or news articles, by frequently linking different attributes of environmental issues such as Plastic Soup in their communications to influence public opinion on those issues.

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