=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== https://ceur-ws.org/Vol-2554/paper_01.pdf
                 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-
ˆ General and reference  Surveys and overviews;                      proaches to recommender system implementation. Finally,
Empirical studies; ˆ 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


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