=Paper=
{{Paper
|id=Vol-2554/paper1
|storemode=property
|title=Public Service Media, Diversity and Algorithmic Recommendation: Tensions between Editorial Principles and Algorithms in European PSM Organizations
|pdfUrl=https://ceur-ws.org/Vol-2554/paper_01.pdf
|volume=Vol-2554
|authors=Jannick Kirk Sørensen
|dblpUrl=https://dblp.org/rec/conf/recsys/Sorensen19
}}
==Public Service Media, Diversity and Algorithmic Recommendation: Tensions between Editorial Principles and Algorithms in European PSM Organizations==
Public Service Media, Diversity and Algorithmic Recommendation Tensions between Editorial Principles and Algorithms in European PSM Organizations Jannick Kirk Sørensen Center for Communication, Media and Information Technologies (CMI), Aalborg University Copenhagen js@cmi.aau.dk ABSTRACT as they in return for public funding have obligations to pro- Public Service Media (PSM) websites are an interesting case duce and promote content that e.g. strengthen local language for the implementation of recommender systems for media and culture, help inclusion and societal cohesion, foster demo- personalization, as the PSM organizations need to balance cratic processes, reflect diversity in opinions and worldviews. the optimization of exposure with traditional but ill-defined In the age of broadcasting, priority was given to this type of PSM policy goals such as fairness, viewpoint diversity and content by scheduling strategically before or after popular transparency. Furthermore, the mathematical logic of rec- content. When content exposure is personalized via a recom- ommender system needs to be adapted to the legacy broad- mender system, the question emerges: To which extend will casting scheduling and publishing strategies and procedures. the algorithm and the editors / data curators recommend Finally, as the PSM organizations step into new territories, content that reflects individual user interests if these do not domestication and adaption of the recommender system tech- align with the content obligations? The question is relevant nologies must take place while PSM organizations try to for more than the user experience. The funding and political embrace the new knowledge and new professions associated legitimacy of public service media is closely connected with with recommender systems. Based on 25 in-depth interviews the content obligations. If this content is not being exposed conducted from December 2016 to April 2019, this paper to users, the legitimacy of the institution may be endan- presents a cross-European analysis of the implementation of gered. Conversely, the programming and scheduling strategy recommender systems in nine European public service me- of the PSB and PSM organizations have always been to offer dia organizations from eight countries. The findings indicate popular content, such as music, sports and entertainment that PSM organizations, although viewing personalisation to listeners, viewers and users. How will PSM organizations as competitive necessity, approach recommendation systems approach this balancing? with hesitation in order to maintain core PSM-values in the Based on 25 in-depth interviews with practitioners, like online environment. Furthermore, although the collaborative project leaders, product owners, programmers, data scientists filtering chosen by the PSM organizations indicate a user- and data curators the paper shows how they adopt PSM core centered approach, curation systems on top of recommender values to algorithmic recommender systems. The paper is systems re-install a broadcaster-centric approach. structured as follows: Below we introduce the special require- ments to recommender systems that the PSM context poses. CCS CONCEPTS After that we provide an overview of PSM interviewees’ ap- General and reference Surveys and overviews; proaches to recommender system implementation. Finally, Empirical studies; Information systems Collabo- we point at a fundamental paradox related to the contextual rationality of recommender systems. rative filtering; Personalization. KEYWORDS 2 BACKGROUND Public service media is often linked to a set of ideals—the Diversity, Filter bias, Editorial control, Public service media, PSM remit [27]. UNESCO [43] lists as principles for public Recommender systems, Curation systems service broadcasting: ∙ Universality 1 INTRODUCTION ∙ Diversity Recommender systems have been build to serve individual ∙ Independence interests by selecting and filtering content, while public ser- ∙ Distinctiveness vice broadcasting traditionally have aimed to reach the whole population with content that editors think is beneficial for Public service media want to be agenda-setters with a mis- citizens. The intention is to mediate a public sphere. Bringing sion of e.g. strengthening social cohesion, facilitating demo- the two entities sounds as a contradiction in terms. Public cratic discussions, supporting national culture and language, service media have a special position in the media landscape, ensuring freedom of speech, supporting cultural diversity [9]. Diversity and inclusion are today important values, e.g. in the Copyright © 2019 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0). BBC [2]. Nissen [31] argues that “influencing the listener’s or viewer’s choices, and thus media consumption pattern is INRA 2019, September 16–20, 2019, Copenhagen, Denmark Jannick Kirk Sørensen the very reason why public media were established and why The case of recommender systems in the context of pub- their existence has been upheld even in times of abundant lic service media has earlier been discussed at RecSys in a media supply.” (p. 69) keynote by Berry from Canadian CBC [3], and by Fields, Idealized, the principle for selecting and recommending Jones and Cowlishaw from the BBC [11]. Furthermore, Van content to the audience is defined by a consensus about what den Bulck and Moe [45] compare public service media orga- citizens should learn and know to participate in a society, cf. nizations’ different strategies in respect to personalization, the classic BBC motto “enlighten, educate and entertain” [35]. with the Belgium VRT and the Norwegian NRK as case stud- In reality, the production and exposure in the public service ies. Pöchhacker et al. [34] analyze the implementation of a mass media has been and still is shaped by conflicting societal recommender system in a German context, discussed in [36]. interests, opportunistic possibilities and media politicians’ Sørensen [37] analyzes early attempts to personalize PSM expectations. online services. Bodo [4], Kunert and Thurman [25], Thur- Traditional algorithmic recommendation, i.e. collaborative man and Schifferes [41] analyze private and public media use filtering (CF) [18, 19, 23], on the other side addresses the in- of personalization. dividual user to optimize the exposure of content and, ideally, protecting him / her from information overflow. Typically, 3 METHODOLOGY no communicative intention is associated with the recommen- Using convenience sampling, a set of case were selected repre- dation. Instead, key performance indicators (KPIs) are being senting both on-going projects and recommender systems in measured. production. A sampling criteria is that the PSM organization Will PSM organizations stick to the broadcaster-centric is a member of European Broadcasting Union (EBU) and approach that prioritizes certain content or will they embrace located in Europe. Among the 54 EBU member organiza- the customer-choice logic of personalization? A key to this tions located in Europe1 , we selected nine cases of develop- question is how diversity is created in the recommendations: Is ment or implementation of recommender systems. Developers, it defined by an editor defined to reflects different viewpoints data scientists and project leaders from the nine PSM or- (source diversity) [29], or is calculated to reflect the global ganizations were interviewed via semi-structured in-depth diversity of items available for recommendation, the diversity interviews. within the recommended items (intra-list diversity) [8], or Interviewees were selected based on their direct involve- does it take the point of departure in the users’ profile [46]? ment in the development or implementation of a recommender Due to the special content obligations, diversity is a sensitive system. The strategic management level has thus not been topic in public service media. included. The interview data was collected between December In media politics, the diversity of media content providers, 2016 and April 2019. Additionally, developers, data scientists ownership and media outlets is a measure of a well-functioning and project leaders from five other European PSM organiza- democracy [17, 29]. In the area of news and media, a specific tions were interviewed: ARD (Germany), FranceTv (France), concern has grown that algorithmic recommender systems MDR (Germany), Radio France (France), RAI (Italy), YLE will lead to a loss of exposure diversity [29]. Subsequently, (Finland). much discussion has revolved around filter bubbles [32] caused The interviews, 25 in total, were conducted as semi-structured by collaborative filtering [5, 14, 30]. Suggestions for regulat- expert interviews based on a question guide [26]. The ques- ing exposure diversity have been proposed by [6, 7, 16, 17] tion guide was adjusted to reflect both the development of but also criticized [39]. Recently, measurements in a news the projects over time, as well as the insights gained during context have however showed that algorithms are as good at the research. The interviews were audio-recorded (in total: providing diversity as human editors [28] and that the prob- 820 minutes), transcribed and topic coded. lem of filter bubbles may be overestimated [47]. Fletcher [13] Most PSM organisations implement content-based filtering finds that news repertoires of users who find news via search (C-B) and collaborative filtering (CF). A number of PSM engines have a more diverse and balanced news consumption, organisation also report to use a diversity module for rec- while [12] reaches a more mixed conclusion. However, diver- ommendations. Finally, some PSM organisations use the sity exposure concerns are still associated with algorithmic recommender system as part of a curation system, controlled recommender systems [10, 15]. by editors and scheduling staff via business rules. While diversity in itself is a problematic concept [22], achieving diversity in algorithmic recommendations is a prob- 4 ANALYSIS lem with importance for user experience and cross-selling of Reflecting our inductive and praxis-oriented approach, the products [8, 24]. Sørensen and Schmidt [39] indicates that topics discussed by and with the interviewees can be grouped there might exist a gap between how diversity is understood in the following categories. and treated as a mathematical concept in recommender sys- ∙ Organizational Opportunities and Challenges tems [8], and how media policy and editors construct the ∙ Diversity, Exposure and PSM Obligations concept [29]. Where the former seldom takes the semantic ∙ Editorial control and curation vs. automation context in consideration, the core parameter in the latter is ∙ KPIs - evaluation of exposure contextually and socially defined view-point diversity [1]. 1 https://www.ebu.ch/about/members accessed April 2, 2019 Public Service Media, Diversity and Algorithmic Recommendation INRA 2019, September 16–20, 2019, Copenhagen, Denmark Table 1: Cases of PSM recommender systems PSM organization Country Type of system Status Provider BR Germany CF, C-B and Diversity module Running In-house (PEACH) DR Denmark Curation system Implementing Vendor EER Estonia C-B, stemming module Development In-house NPO Netherlands C-B (CF in production) Running In-house NRK Norway CF, C-B and Diversity module Running In-house RTBF Belgium CF, C-B Running In-house (for sale) RTVE Spain CF, C-F Developing External, custom built SR Sweden CF, Curated playlists Running Partly In-house, partly vendor ZDF Germany CF, C-B, Sequence and Curation system Running In-house ∙ Trust and Transparency main motive for implementing recommender systems. The ex- ∙ Build or buy? posure of the less used content is part of the PSM obligation In the following lines we will summarize the interviewees’ of promoting diversity. But interviewees are also concerned viewpoints on each of the topic areas, and discuss the per- of being accused for producing filter bubbles. Recommender spectives. systems for PSM organizations must put a special emphasis on diversity. In some cases, software modules have been build 4.1 Organizational Opportunities and to calculate diversity of the recommendations3 , but the idea Challenges of regulating diversity via algorithms is generally received re- luctantly. Most interviewees have an editorial understanding A notion of strategic necessity was e.g. expressed Decem- of diversity, arguing that the diversity is ensured by the global ber 2016 by the EBU President Jean-Paul Philippot at a set of items (videos) available in the system. In one case, a Recommender Systems workshop for EBU members: “While business rule ensures that the user, after having seen two PSM still detain the largest audience in the EU, they should pieces of content of the same genre is presented to two other take these trends [increasing use of on-demand services] into genres, e.g. two fiction videos are followed by documentary account if they want to keep an advantage over Netflix and and news videos. The solution is by the interviewee described other competitors. This migration implies new tools such as as “simplistic”, as the genre may not indicate diversity. The efficient recommender systems, new skills, and new mindsets.” 2 issue of viewpoint diversity [1] was expressed as a problem The objective here is the competitiveness of public service by one interviewee, discussing whether a system is needed media. to make sure that a users watches different political parties’ Being able to offer personalization is seen as an important video presentations prior to elections. value proposition. Users expect personalization features, e.g. Clear and official definitions of diversity are typically miss- My page or Recommended to you to see the PSM web service ing, leaving data curators on their own. Defining diversity has or app as a competitive alternative to other media providers. traditionally been an organizationally sensitive task, as diver- Furthermore, the technical departments in the PSM organi- sity is understood differently by media politicians, by PSM zations want to build know-how on data-driven business, and professionals and users. The absence of a formal definition management wants to explore demand-driven production of has traditionally enabled PSM editors to navigate between content and position the organization in the media market. conflicting ideas of diversity without direct confrontations. However, the data analysts, programmers and data cu- rators complain that it is difficult to explain recommender 4.3 Editorial control and Automation systems to editors and journalists. E.g. the value of good meta data is not always clear to the editorial staff. Many During the two years of interviewing, we have observed a editorial assistants may simply copy-paste generic meta data shift in PSM staff understanding of recommender systems: descriptions from one episode item to the next resulting in Initially skeptically approached as automated black boxes, low-quality recommendations. recommender systems are now typically used as part of a curation system. Furthermore, editors have gained control 4.2 Diversity, Exposure and PSM over the recommendations, e.g. by setting business rules for certain slots on the page, by the tagging of content items or Obligations by giving priority to certain content in the keyword search The improvement of user loyalty and content exposure, par- system. Many systems also have a manual override function- ticular of long-tail content and under-performing content, is a ality. 2 RTBF - EBU Workshop on Algorithms and Soci- 3 ety 12-13/12 2016, accessed September 10, 2018 at the PEACH recommender system, produced in collaboration between https://www.ebu.ch/contents/events/2016/12/big-data-initiative- BR (Germany), RTS (Switzerland) and EBU https://peach.ebu.io/ workshop-algorithms-and-society.html technical/tutorials/algorithms/diversified/ accessed October 1, 2018 INRA 2019, September 16–20, 2019, Copenhagen, Denmark Jannick Kirk Sørensen A challenge for data curators is the manual configuration monitor the level of transparency of the PSM recommender of business rules. Several interviewees report experiences systems, to protect users’ rights of transparency [20] and the with the content-based filtering that recommended out-dated competitive balance between commercial media and publicly sports- or news shows or inappropriate content: e.g. hard funded media. debating on Islam after a satirical video on the same topic. Maintaining the high level of editorial quality in the auto- 4.6 Build or buy? mated recommendation is a challenging task. Most of the PSM organizations in our survey have either The business rules, the curation and the placement of the build their in-house systems with help of open-source tools, or algorithmic recommended content typically at the bottom commissioned external developers to develop a systems that of the page or after video play-back imply that users only later can be transferred to the PSM organization. Only one to a limited degree experience personalisation at the pages. PSM organization (DR in Denmark) has chosen a proprietary There is only few opportunities to show users new, unknown solution offered by an external provider. DR argues that the content. As novelty of the content often is a criteria for PSM organization neither is nor should be a technology recommendation the pool of relevant content is reduced. organization; it should focus on content. Furthermore, as content similar to the previous watched is As reasons for building own systems, interviewees pro- given priority such as the next episode of a show / season the vide different reasons. For some, the in-house competence window for diversity exposure is even smaller, interviewees building that enables fine-tuned configuration, control and report. development is important. Other interviewees emphasize the complex organizational (data-) structures and the special 4.4 KPIs - the evaluation of exposure requirements of PSM as motivation for custom-built systems. With personalized recommender systems, PSM organizations Some interviewees explained that no usable external solu- inherit a concept that has been invented for commercial tions were available at project start, thus stimulating them purposes [33]. As PSM organization have other objectives to develop own systems. In the case of Estonia, the special than e.g. improving click-through-rates, other KPIs must grammar of the Estonian language forced developers to build be defined. However, defining PSM-specific KPIs, e.g. for their own stemming tools. Finally, ensuring the technical the diversity of the recommendations, social cohesion or the independence of PSM organization in a future with IP-based public service value is a challenging and controversial task. In- media consumption plays for many organizations a role for terviewees thus report that they mainly use KPIs internally building their own systems [40]. in the development team to benchmark algorithm perfor- The lack of systems addressing specific PSM requirements mance. The management levels of PSM organizations have (e.g. diversity) prompted two software projects to build so far not shown much interest in KPIs from the recom- generic PSM recommender solutions: The PEACH project mender systems; broadcast-related KPIs have a much bigger was initiated by Bayerische Rundfunk (BR) in Germany, and managerial attention. PSM managements typically see the al- continued as a EBU project4 . In parallel, a system was devel- gorithmic recommendation projects as experiments. In many oped by the Belgian PSM organization RTBF. In both cases, organizations editors and journalists however have access to the interest from other PSM organizations to implement has dashboards on online performance of the site and the content. however been limited. 5 DISCUSSION AND CONCLUSION 4.5 Trust and Transparency PSM organizations are hesitant to personalize the content Interviewees all stress that a PSM organization has a par- exposure. Organizational acceptance of algorithmic recom- ticular duty in explaining users how recommendations are mendation is one barrier, the broadcast work-flow, lack of being made, and how personal data is being treated. While good meta-data and technical skills are other barriers. With the latter, at least from a legal perspective is covered by algorithmic recommendation legacy public service broadcast- GDPR, the former is a bigger challenge. While content-based ing organizations are stepping into unknown territory. On this recommendations more easily can be explained to users, rec- journey, the potential of loosing the core value proposition, ommendations based on more complex data processing are namely the agenda-setting, is felt as a danger. Movements hard to explain in details to users. The problem of explaining in the wilderness are thus careful, as PSM organizations are recommendations is discussed in general terms e.g. by [42], vulnerable to political and commercial accusations of being but what specifically are PSM users’ expectations concern- too commercial, too personal, too little distinctive or for lack ing transparency? Interviewees agree that the PSM context of different types of diversity could hurt the organizations is particular sensitive as public service media stands out severely. as trusted institutions [38, 40]. Thus full transparency or However, a more profound reason for the hesitation could at least openness on recommendations is needed, however be suggested, based in a paradox: The public service mis- competitive interests may prevent PSM organisations from sion is - as stated - to enlighten, inform and educate. The sharing too many details about their recommender systems. role of entertainment has either been the sugar-coating on However, the special position of PSM organisations in the 4 media markets [21, 31, 44] may call for media regulation to https://peach.ebu.io accessed 2019-08-18 Public Service Media, Diversity and Algorithmic Recommendation INRA 2019, September 16–20, 2019, Copenhagen, Denmark the pill of information, part of the provision of diversity or [17] Natali Helberger. 2015. Public Service Media - Merely Facilitating the justification of the license fee. Based on the apparent or Actively Stimulating Diverse Media Choices? Public Service Me- dia at the Crossroad. 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