Affect in science communication: a data-driven analysis of TED Talks on YouTube

ARTICLE https://doi.org/10.1057/s41599-023-02247-z OPEN Affect in science communication: a data-driven analysis of TED Talks on YouTube 1234567890():,; Olivia Fischer 1,5, Loris T. Jeitziner2,3,5 & Dirk U. Wulff3,4 ✉ Science communication is evolving: Increasingly, it is directed at the public rather than academic peers. Understanding the circumstances under which the public engages with scientific content is therefore crucial to improving science communication. In this article, we investigate the role of affect on audience engagement with a modern form of science communication: TED Talks on the social media platform YouTube. We examined how two aspects of affect, valence and density are associated with public engagement with the talk in terms of popularity (reflecting views and likes) and polarity (reflecting dislikes and comments). We found that the valence of TED Talks was associated with both popularity and polarity: Positive valence was linked to higher talk popularity and lower talk polarity. Density, on the other hand, was only associated with popularity: Higher affective density was linked to higher popularity—even more so than valence—but not polarity. Moreover, the association between affect and engagement was moderated by talk topic, but not by whether the talk included scientific content. Our results establish affect as an important covariate of audience engagement with scientific content on social media, which science communicators may be able to leverage to steer engagement and increase reach. 1 University of Zurich, Zurich, Switzerland. 2 University of Applied Sciences and Arts Northwestern Switzerland, Olten, Switzerland. 3 University of Basel, Basel, Switzerland. 4 Max Planck Institute for Human Development, Berlin, Germany. 5These authors contributed equally: Olivia Fischer, Loris T. Jeitziner. ✉email: HUMANITIES AND SOCIAL SCIENCES COMMUNICATIONS | (2024)11:80 | https://doi.org/10.1057/s41599-023-02247-z 1 ARTICLE T HUMANITIES AND SOCIAL SCIENCES COMMUNICATIONS | https://doi.org/10.1057/s41599-023-02247-z Introduction he digital age presents both opportunities for and challenges to science communication. Communication hubs such as Twitter, Facebook, and YouTube offer unprecedented reach for scientific content and interaction with the public (Collins et al. 2016), thereby making science more accessible for scientists and laypeople alike. With engagement tools such as likes, dislikes, comments, and shares, members of the general public now no longer simply consume scientific content but can also disseminate it. As a result, scientific content that does not engage the public may never reach a large audience. In the oversaturated and highly competitive environment of social media, how can scientists make their voices heard? Science communication via social media differs in at least two important respects from traditional peer-to-peer science communication. First, because social media users tend to consume content more superficially (Boczkowski et al. 2017), surface-level aspects of content such as choice of language are likely more important for gaining a competitive advantage. Second, content on social media can be shared indirectly, through recommender systems (Covington et al. 2016), as well as directly. These differences introduce strong positive feedback between user engagements, which can greatly amplify the reach of highly engaging content (Aldous et al. 2019; Davidson et al. 2010; Hoiles et al. 2017). This means that scientists rely on laypeople to propagate their messages on social media, which in turn incentivizes scientists to pay attention to the aspects of science communication that make it more engaging. In this article, we investigate affect as one aspect of science communication that may be instrumental for effective science communication (Milkman and Berger, 2014). Past work has found that New York Times articles using more affect-rich language were more likely to make the New York Times mostemailed list (e.g., Berger and Milkman, 2012). There is also evidence that scientific findings described in a more affective manner are more likely to be shared (Milkman and Berger, 2014) and tend to garner more citations (Fronzetti Colladon et al. 2020). However, the potential link between affect and engagement as a driver of dissemination has not been systematically investigated for social media-based science communication (see Davies, 2019; Davies et al. 2019; Osseweijer, 2006). We aim to fill this gap with a data-driven analysis of engagement with TED Talks on the social media platform YouTube. TED Talks are short recorded presentations on technology, entertainment, and design; many address basic and applied science. TED Talks are therefore studied as a modern form of science communication (e.g., Gheorghiu et al. 2020; MacKrill et al. 2021; Sugimoto and Thelwall, 2013; Verjovsky and Jurberg, 2020). The transcripts of all talks featured on the TED website (www.ted.com) can be used to derive their affective features. TED Talks are shared on the TED website and on the organization’s YouTube channel, which has a total of 19.8 million subscribers and over two billion video views1. The popularity of TED Talks on YouTube reflects that they are targeted at a lay audience and contain less jargon (Rakedzon et al. 2017; Sharon and BaramTsabari, 2014); these talks therefore offer a rich data trove on public engagement that can be linked to the talks’ affective features. There is a growing body of work on social media-based science communication (see Allgaier, 2020; Brossard, 2013; Kohler and Dietrich, 2021) and, in particular, science communication on YouTube. Past work has focused on understanding the role of characteristics of video presenters for user engagement, including their gender (Amarasekara and Grant, 2019), professional background, and perceived authenticity (Kaul et al. 2020), as well as on understanding the viewer’s psychological processes, for 2 instance, by tracking eye movements (Boy et al. 2020) or analyzing the semantic and emotional content of YouTube comments (Amarasekara and Grant, 2019; Shapiro and Park, 2015). However, to the best of our knowledge, the use of affect in the communication of the scientific content itself has not been investigated as a potential driver of public engagement. We seek to contribute to the literature by addressing two research questions: How is affect used in TED Talks in contrast to other science communication media, and is affect as a surfacelevel characteristic of science communication associated with audience engagement in the social media environment of YouTube? We adopt a data-driven approach to address these questions. Our analysis establishes, for the first time, affect as a potential driver of lay audience engagement with science communication on social media. A database of TED Talk transcripts and engagement on YouTube We downloaded all available transcripts and corresponding information (e.g., t (...truncated)