Scholarly article on topic 'Platform affordances and data practices: The value of dispute on Wikipedia'

Platform affordances and data practices: The value of dispute on Wikipedia Academic research paper on "Media and communications"

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Academic research paper on topic "Platform affordances and data practices: The value of dispute on Wikipedia"



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Platform affordances and data practices: The value of dispute on Wikipedia

Big Data & Society

January-June 2016: 1-16

© The Author(s) 2016

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DOI: 10.1177/2053951716653418


Esther Weltevrede and Erik Borra


In this paper we introduce the device perspective as a methodological contribution to platform studies. Through an engagement with debates about the notion of affordances, which focus on the relation between the technical and the social, we put forward an approach to study the production of data within platforms by engaging with the material properties of platforms as well as their interpretation and deployment by various types of users. As a case in point, we study how the affordances of Wikipedia are deployed in the production of encyclopedic knowledge and how this can be used to study controversies. The analysis shows how Wikipedia affords unstable encyclopedic knowledge by having mechanisms in place that suggest the continuous (re)negotiation of existing knowledge. We furthermore showcase the use of our open-source software, Contropedia, which can be utilized to study knowledge production on Wikipedia.


Digital methods, platform studies, affordances, devices, Wikipedia, controversy mapping


This paper offers a methodological contribution to platform studies by advancing what we call a device perspective. Two of the most well-known strands in platform studies are platform politics, which focuses on how platforms negotiate the different interests of "users, clients, advertisers and policymakers" (Gillespie, 2010: 1), and the approach that regards platforms as architectures to be built upon, which studies how platforms suggest specific uses of their features and data (Bogost and Montfort, 2009; Helmond, 2015). Both perspectives recognize how platforms preconfigure specific practices through designed features and functions. In this paper, we put forward an approach to study both the affor-dances of platforms as well as how they are interpreted and deployed by users and other parties—what we term data practices, how this shapes the production of data within platforms, and how such a dual approach to platforms can be made productive for digital research. More specifically, we study how the affordances of Wikipedia are deployed in the production of encyclopedic knowledge and how this can be used to study unstable knowledge and controversy more specifically.

In its elementary definition, affordances characterize the actions that are suggested by an object or an environment.1 Currently, the term gains traction in debates about the relationship between the technical and the social and is used to provide ways to explore how the material qualities of technologies suggest certain practices while they also accommodate (un)intended uses (Bucher, 2012; McVeigh-Schultz and Baym, 2015; Nagy and Neff, 2015). It has been argued, however, that the focus on affordances offers a "false" compromise that leaves little more than a description of the material properties of a device (see, e.g., Rappert, 2003). Remedially, Nagy and Neff (2015) propose the use of "imagined affordances" that emerge between users' perceptions, the intentions of designers, and the materiality of technologies. Such a corrective seeks to include the psychological complexity of user

University of Amsterdam, The Netherlands Corresponding author:

Esther Weltevrede, University of Amsterdam, Turfdraagsterpad 9, Amsterdam, NH I0I2XT, The Netherlands. Email:

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interactions when studying the affordances of devices—as was initially conceptualized by Gibson (1977). This paper responds differently to the challenge and advances a conceptual and methodological approach that includes both the affordances of a platform as well as the processes, uses, and practices that emerge in negotiation with it; what we refer to as the ''device cultures" of these platforms (also see Rogers et al., 2013).

Devices are not mere tools; they are also complex and unstable arrangements that bring together a variety of people and objects with particular purposes.2 We are drawn to the term device because it allows us to bring together online platforms both as an object (Lury and Wakeford, 2012: 9) and at the same time as a method that activates specific processes in the platform (Callon et al., 2007; Law and Ruppert, 2013; see also Weltevrede, 2016). Device cultures can then be defined as the interaction between users and platform; how activity is imagined, curated, and prescribed into the platform architecture; how affordances are activated by the (un)intended uses and practices that take place on and within platforms; and how the data is collected and processed by the platform. In other words, the platform architecture suggests certain practices and uses, and contains the traces of platform activity in the form of data, whether unprocessed or in aggre-gate—or any algorithmically processed form, such as the variants on "popular," "trending," or "relevant" content. Device cultures do not offer ways to study the complexity of human psychology as originally conceptualized with the notion of affordances (Gibson, 1977; Nagy and Neff, 2015), but can be invoked to empirically study a platform and the data that circulate through it by focusing on the specific articulations of uses, practices, and platform dynamics.

In the remainder of this paper, the device perspective is further developed through an empirical case study concerning the Wikipedia article on "global warming.'' We analyze Wikipedia's platform affordances, code ecologies, and also the uses of, and practices in, the platform, while critically reflecting on the relations between method and medium. We will thus approach the Wikipedia article on global warming as the result of negotiations and interactions between Wikipedians and the affordances of the Wikipedia platform, in order to understand the substance and dynamics of knowledge production on Wikipedia.

Wikipedia as a device for unstable knowledge

With the device perspective we take up the invitation extended by software studies to examine the ''conditions of possibility'' which software establishes (Fuller, 2008: 2). Here our objective is to analyze

Wikipedia's device culture—the platform architecture and the assumptions, practices, and uses inscribed into it—to study how knowledge production about global warming has evolved over time.

Wikipedia's "purpose," as described in the article dedicated to it, "is to benefit readers by acting as an encyclopedia, a comprehensive written compendium that contains information on all branches of knowledge'' (Wikipedia contributors, 2014g). In other words, Wikipedia aims at "encyclopedianess," the state or quality of being an encyclopedia. This encyclopedianess is defined in terms of exhaustiveness, including all branches of knowledge, and reliability (Roblimo, 2004; Sanger, 2001). In order to achieve encyclopedianess, consensus is the primary way to make editorial decisions, as it is the principal guideline for knowledge production and conflict resolution (Wikipedia contributors, 2014b). Phrased differently, the different interests of Wikipedians and the potential disputes emerging from them in the content of the articles are negotiated with policies and guidelines with reaching consensus as the main method.

Wikipedia furthermore affords unstable knowledge by putting mechanisms in place that suggest that encyclopedic knowledge is never complete. Consider how Wikipedia articles are never finished and fully locked for further editing, which is illustrated by the widespread use of "stubs," or very short beginnings of articles inviting other Wikipedians to edit. Instead, on Wikipedia encyclopedianess is designed to shape the process of knowledge production and it offers guidelines to help resolve disputes over content. The instability of encyclopedic knowledge can take shape in different forms, such as controversial, lively, fluctuating, popular, or happening, which are informed by different dynamics of change to existing knowledge. Consider, for example, the difference between changes to articles about topics that are "in the news'' compared to those of topics that are highly controversial. The focus of our analysis is on controversy, to which we return in the following section. First, we address the key parts of Wikipedia's device culture that are called upon in the case study.

The first aspect of Wikipedia's device culture is architectural, namely its content management system, the MediaWiki software (MediaWiki Contributors, n.d.). Like any wiki, it is a web application where anyone can edit content in collaboration with others. A key part of wikis is the use of "free links'' markup, where links are written between brackets to refer to other articles relevant in the context of the current one. The MediaWiki software organizes the front-end (i.e., the encyclopedic entry) and the back-end (e.g., the edit history and talk pages) in a distinct way, by using namespaces, which are prefixes for a given article in order to distinguish between different functions (e.g.,

"Talk:" or "User:"). Each page thus has an associated discussion page (i.e., ''Talk:'') where users can discuss the content of the article separate from the article. The edit history of an article provides access to every version of the article and allows one to compare two article versions. Although these back-ends are visually complex, they are publically accessible and their workings are well documented.3

The Wikipedia architecture is often conceptualized in terms of how it facilitates collaborative openness, generally understood in terms of its open editing culture, but extending into its organizational structure, decision-making, data, and software development.4 How the platform conceives of knowledge production through the notion of openness is continued in the ability to adjust and tinker with the platforms' core functionalities and features. The performativity of Wikipedia is thus open to the addition of unanticipated features and affordances. In other words, the affordances of Wikipedia are not only defined by the MediaWiki CMS, but are instead a cocreation of externally developed and hosted pieces of code, which Stuart Geiger has referred to as ''bespoke code'' (2014). Examples of bespoke codes are the often celebrated {{citation needed}} tag and the army of bots that detect and revert vandalism, create pages, and perform content maintenance tasks (also see Niederer and Van Dijck, 2010).5

Wikipedia's policies and guidelines constitute the second part of its device culture: principal guidelines for knowledge production and conflict resolution. To maintain its encyclopedianess Wikipedia thus has mechanisms in place to reach consensus, most notably through the three core content policies ''neutral point of view'' (NPOV), "verifiability," and ''no original research'' (Wikipedia contributors, 2012). The NPOV requires that ''all notable and verifiable points of view'' are included in an article. The term ''neutral'' is somewhat misleading as the policy does not forbid perspectives or views, but rather dictates that articles must not take sides, but rather should explain the sides, fairly and without bias: Wikipedia seeks to ''describe disputes, but not to engage in them'' (Wikipedia contributors, 2013c). "Verifiability" entails that claims and facts must be attributed to reliable external sources as ''readers must be able to check that Wikipedia articles are not just made up'' (Wikipedia contributors, 2014h). This policy is very closely linked to ''no original research'' which states that ''Wikipedia does not publish original thought'' and ''all material in Wikipedia must be attributable to a reliable, published source'' (Wikipedia contributors, 2014f). These policies together prescribe the norms for practices in knowledge production on the online encyclopedia.

The third part of Wikipedia's device culture consists of the Wikipedians continually negotiating editorial

changes in the system. When editors are in dispute, they call upon the Wikipedia policy to reach consensus (Niesyto, 2011). Editors of Wikipedia may be anonymous, in which case an IP address is used in the edit history pages, registered as a user with a specific username, or an automated tool or bot. Everyone is allowed to edit articles (unless blocked), even without logging in; although logging in has advantages, however, like the ability to create new articles. The tools editors have at their disposal for conflict resolution depend on their level of access. These are hierarchical and range from the blocked user with the fewest permissions to the administrator, or sysop, with high permission levels, who may for instance include locking articles for further editing (Wikipedia contributors, 2013d).6 The various types of editors negotiate within the content management system with reference to the policies and guidelines in order to comply with Wikipedia's encyclo-pedianess and, in case of dispute, to seek consensus. In the following, we will consider how one may repurpose these Wikipedia mechanisms aimed to achieve consensus by aligning platform affordances with the research objective to study controversies.

Controversy research with Wikipedia

By approaching Wikipedia as a device that activates continuous changes to existing knowledge, the article's edit history and talk pages provide a detailed documentation of the processes of negotiation that have taken place. Our case study focuses on the article about global warming and is analyzed with the help of our open-source and freely available software, Contropedia,7 which takes into account Wikipedia's device culture and allows for the study of the substance and evolution of controversies within Wikipedia articles. In what follows, we reflect on the methodological choices made to focus our analysis on controversy. Our contribution is positioned in relation to previous research into conflicts and coordination on Wikipedia.

First, the choice of the article "global warming" is instructive in the type of instability found in the article, as it is about a key societal controversy as well as one of the larger ongoing controversial articles on Wikipedia, being on the list of controversial issues since 2001.8

In Wikipedia, reverting an article to a previous version is a key mechanism for repairing detrimental edits to an article and removes the changes introduced in all intermediate edits (Wikipedia contributors, 2013a). So-called edit wars are arguably the most extreme example of actors (thoroughly) disagreeing on Wikipedia. They occur when authors repeatedly revert each other's edits without resolving the disagreement by discussion, and instead end up in so-called circular editing (Wikipedia contributors, 2013b). Although reverts are generally

considered to be a good way to detect controversy, our focus is not solely on reverts and edit wars; rather, the aim is to include more moderate and subtle disputes about content, too.9

This brings us to the second consideration, as the understanding of controversy put forward here is slightly more nuanced than those offered by others who have studied controversy on Wikipedia. We follow controversy mapping's notion of controversy, which can be summarized as "situations where actors disagree (or better, agree on their disagreement)'' (Venturini, 2010; also see Latour, 2005). This understanding can be said to be more inclusive as it might also entail disputes that not necessarily result in edit wars, but for instance focus on the use of specific vocabulary or a reference. In fact, our analysis showed that most reverts just undo vandalism: those deliberate attempts to compromise the integrity of an article by, for instance, deleting sections, inserting irrelevant obscenities or nonsense. From a controversy mapping perspective, vandalism is not necessarily considered a source of disagreement because it often does not introduce a point of view (POV), bias, argument, or opinion. The aim is thus to detect and exclude vandalism by discarding those edits marked as vandalism edits in the edit history.10 In addition, both punctuation and

maintenance edits are filtered out, as well as edits merely inserting new content (i.e., as opposed to deleting or altering it), as changes to existing content convey that an editor disagrees with it and seeks to improve the sentence. After such filtering of the edit history, only substantive disagreeing edits to the content remain. This substantive edit history is subsequently analyzed to indicate which issues have been the loci of most edit activity.

Third, in order to determine around which issues the controversy revolves, the device perspective leads us to focus on wiki links. Consider for example Figure 1, which shows the article on "global warming'' with all plain text blanked out to draw attention to the activating content, the affordances, of the frontend of a Wikipedia article, such as links to other articles, references, and images. Wikipedia guidelines indicate that internal links and references should be used to "increase readers' understanding of the topic at hand''; a phrase should only be linked when it is relevant for the current article (Wikipedia contributors, 2014d). Intuitively, wiki links are important as they refer to things that themselves are "matters of concern'' (Latour, 2005).11 The device culture perspective reveals the work put into a link, by examining the substantive disagreeing edits related to that link.

Figure 1. The English Wikipedia article on ''global warming'' on 12 January 2013 with all plain text blanked out to emphasize Wikipedia's activating content. Visualization created in Firefox, 2013.

Fourth, the controversialness of wiki links is calculated by counting the substantive edits to the sentences in which these wiki links appear. However, the more wiki links appear in an edited sentence, the less the edit focuses on one particular wiki link. For every edited sentence, we thus divide the weight attributed to a wiki link by the total number of wiki links that appear in that sentence of a particular revision. To find out which wiki link is most controversial, or put differently, around which terms most negotiations took place, the article's wiki links are ranked in descending order of weighted substantive edit counts. The ranking, then, conveys those wiki links (issues) yielding most substantive disagreement in the article.12

Concluding, by aligning the research objective with the device culture of the platform, the device perspective offers a different approach to controversy than the definition of controversy used by most Wikipedia studies into controversial articles. Whereas most conflict and cooperation studies focus on the revert as the principal indicator of controversy, we surface all substantive topical edits by recognizing that wiki links in Wikipedia signify matters of concern in that article, by excluding maintenance edits as well as vandalism, by calculating a controversy score per wiki link, and by grouping the substantive disagreeing edits per wiki link. The groups of substantive edits per wiki link allow for an easy inspection of the relevant edits, so that the specific references to policies, guidelines, and discussion threads can be analyzed. In the following, we present a case study that makes use of the concepts and measures addressed in this section and that are facilitated by Contropedia.

Case study: Global warming

In 2007, the Intergovernmental Panel on Climate Change's (IPCC) Working Group 1 released its fourth assessment report (AR4) (Solomon et al., 2007). It concerned the physical science basis of the natural and human drivers of climate change and concluded that ''warming of the climate system is unequivocal," and that ''most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations'' (Solomon et al., 2007: 5, 10). Although the report cited thousands of scientists and demonstrated a scientific consensus that the climate is warming and that this is driven by human activity, a minority of scientists opposed the outcomes of the report. Media trying to provide objective information about global warming faced the danger of being trapped into providing the public with a ''false balance,'' by providing equal coverage to both views, thus giving ''disproportionate weight to minority views'' (BBC Trust, 2011: 58, 66).

In addition to more traditional mass media, Wikipedia is an important source informing the public understanding of science and public opinion on climate change more specifically. In what follows, we explore what Wikipedia can add to our understanding of the controversy surrounding global warming and more specifically, we focus on how Wikipedians negotiate their differences on the system, in reference to policies and guidelines. This case study is facilitated by Contropedia, which embodies the device perspective and builds on platform features and functions. By analyzing the data of the edit history and talk pages of the Wikipedia article on global warming, Contropedia allows for the analysis of the controversies that played out within said article. In particular, the role of the IPCC and its AR4, of scientists denying that global warming is happening at all, and of those refuting that global warming is caused by human activity is analyzed. More generally, we tried to better understand what is, or was, controversial about the article. What are current and past hot topics of dispute? Did dispute about parts of the content for instance focus on specific subissues? And if consensus was reached, how was this achieved? With Contropedia we condense and group the edit activity and discussions in the talk pages and explore how Contropedia showcases a controversy's evolution on Wikipedia.

Controversialness in the article on global warming. The edit history of the ''global warming" article is condensed by Contropedia's controversy detection algorithm, as explained in the previous section, and visualized as an additional layer to the article (see Figure 2), to provide insight into which issues in the article received most substantive edits. The visualization is a direct modification of the Wikipedia article, conveying its controversial history. The most controversial issues in the lead of the article are "greenhouse gas," ''carbon dioxide (CO),'' and "Intergovernmental Panel on Climate Change.'' The minified view on the right-hand side of the visualization provides a quick overview of those parts of the article that are most controversial and shows that various sections in the article contain multiple controversial issues.

In addition to the layer view of an article, Contropedia also features a controversy dashboard (see Figure 3). This output ranks wiki links in an article by their degree of controversy. Per wiki link, the dashboard displays additional metrics such as the edit activity and controversialness of an issue over time, and the number of users involved in changes to the link. While the layer view shows the anchor text of wiki links that remained in the article until the moment the controversy detection algorithm was run, the dashboard also shows the linked articles that were removed from the main article at the time of analysis.

Figure 2. Controversial issues in the ''global warming'' Wikipedia article. Controversialness was calculated on the full edit history until 16 April 2014. The more controversial a wiki link, the redder it is. The images are converted to gray scale. The link to greenhouse gas is among the most controversial. Partial screenshot from Contropedia, 2015.

The IPCC as a reliable source. One of the top controversial issues is "Intergovernmental Panel on Climate Change'' (see Figure 4). The controversialness bar shows that controversy around the issue sparked in 2005 and that the issue was most controversial throughout 2007. In the following, the edit histories and talk page histories of "Intergovernmental Panel on Climate Change'' in 2007 are analyzed to find out why the issue was controversial at that time.

When clicking the timeline, the substantive edits to the sentences containing the link are listed (see Figure 5). When examining the edits it becomes clear that the prominence of IPCC in the article is the main topic of dispute. This is exemplified by changes in sentences like those explaining that global warming is very likely due to the observed increase in anthropogenic greenhouse gas concentrations (as mentioned in AR4, see for example Figures 5 and 6), and by discussions concerning whether the IPCC should be the primary and authoritative source for this claim.

Further examination of some key changes in the edit history in 2007 shows that on 9 January, before the publication of AR4 IPCC, the link to the IPCC is present in the third paragraph of the lead, together with a quote from IPCC's third assessment report (TAR): ''Models referenced by the Intergovernmental Panel on Climate Change (IPCC) predict that global temperatures may increase by between 1.4 and 5.8°C (2.5 to 10.5°F) between 1990 and 2100'' (Wikipedia contributors, 2007a). Following the release of AR4 in February 2007 the sentence was edited and ''may'' was changed to ''are likely,'' reflecting the IPCC's increased conviction (Wikipedia contributors, 2007b; see also Figure 6). However, some editors consider AR4 to be controversial. This can, for example, be inferred from a revision on 25 March 2007 which attached the POV template to the article (see Figure 7) and added the comment: ''This article is nominated for a check'' (Wikipedia contributors, 2007c).

Subsequently, in the talk page thread on ''POV in the intro'' a direct reference was made to the

Figure 3. Partial dashboard view of the controversial wiki links in the ''global warming'' Wikipedia article on 16 April 2014. Each row represents a controversial wiki link. The rows are ordered by how controversial the wiki link is. The redder the square, the more controversial it is overall. Also shown are a timeline of edits and a controversy bar indicating at which time the element was most controversial. Additionally, the type of element and the number of users editing sentences containing that wiki link are shown. The wiki link ''greenhouse gas'' is the most controversial. Wiki links that do not appear in the current revision (on 16 April 2014) are struck through in the dashboard view. Partial screenshot from Contropedia, 2015.

prominence and authoritativeness of IPCC and AR4 (Wikipedia contributors, 2010a: 24). Some Wikipedians argued that the IPCC figured too prominently in the lead; the discussion revolved around the extent to which this was in line with NPOV policy as well as the extent to which opposing views were significant enough to be taken into account following the ''due and undue weight'' policy.13 In a second talk page thread about the POV template in 2007, the viewpoints on global warming were further discussed in relation to how it was phrased in the lead in March 2007 as: ''this conclusion has been endorsed by numerous scientific societies and academies of science, a few scientists disagree about the primary causes of the observed warming'' (Wikipedia contributors, 2010a). By the end of 2007, the POV template was removed and the link to

the IPCC had moved up to the first paragraph of the lead. Following the discussions, vague terminology such as "numerous" and "few" had been replaced by concrete numbers and organizations that had been verified with reliable sources indicated by the references in footnotes (Wikipedia contributors, 2007d).

An inspection of the substantive edit history and talk pages thus brings to light that the publication of IPCC's fourth assessment report in 2007 was a strong drive not only for the prominence of authoritative sources in the lead but also for changes to sentences containing a link to the article on the IPCC. Wikipedia's ''due weight'' policy provides guidelines on how to deal with the different views proportionately. How the different views are weighed in practice will be elaborated on in the next section.

Figure 4. Detail of the dashboard view ''Intergovernmental Panel on Climate Change'' in the ''global warming'' Wikipedia article on 16 April 2014. The wiki link was most disputed within the article on global warming in 2005 and 2007 while it was involved in a lot of edit activity in the middle of 2006. Partial screenshot from Contropedia, 2015.

intergovernmental panel on climate change

139.54 2W2

intergovernmental panel on climate change has received 409 substantive, disagreeing, edits by 191 users tri 402 revisions 125 deletes, 0 inserts. 0 element changes. 284 sentence changes, 0 section changes intergovernmental panel on climate change was involved In 126 reverts Top sections: abstract (336) scientific opinion (15) overview (15) attributed and expected effects (B) international organizations (7)

Revision Edit

595742&93 [[Climate model]] projections. 95% of which have

reverts 595742523 subsequently failed to match observed global surface temperatures by 3014, projections were summarized in

ths 2007 [[IPCC Fourth Assessment Report|Faurth Assessment Roport}] (AR4) by thB [[Intergovernmental Panel on Climate ChangeJ| (IPCC).


Undid revision 595742200 by [[Special:Contributions/J dey123|Jdey123]] ([[User talk. J dey 123|tatk] ] )Not supported by sources

and clearly a controversial edrt that needs prior discussion



2014-02-16 17:0B:09

695742280 reverted by 595742693

[{Climate model]] projections projections, 95% oi which

have subsequently failed to match observed global surface temperatures by 2014 were summarized In the

2007 [[IPCC Fourth Assessment Report|FDLirth Assessmeni Report]] (AR4) by the [[Intergovernmental Panel on Climate Change]] (IPCC).


2014-02-16 17:02:41

reverts 570013059

A 2013 draft af Ihe [[IPCC Filth Assessment PeportlFifth Assessment Report]] of the United Nations' [[Intergovernmental Panel on Climate Change]I (IPCC) concludes that It Is at least 9S% likely that human activities, not natural climate variations, ate the main cause of warmtng since the 19№s. up from IPCC reports In 2007 (>90%), 2001 (6B%), and 1SS5 <>50%).

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([[User talk:RCralg09|lalk]]) draft publications are non-RS, except to extent we're using them as a source about the draft Itself


[(Climate model]] projections are were summarized in

the 2007 [[IPCC Fourth Assessment Report|Fourth Assessment Report]] (AR4) by the [[Intergovernmental Panel an Climate Change]] (IPCC)

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[[Climate model]] projections are summarized in the 2007 [[IPCC Fourth Assessment Repcrt|Fourth Assessment Report]] (AR4) by the [[Intergovernmental Panel on Climate Change]] [IPCC).


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Figure 5. Detail of the dashboard view of the ''global warming'' Wikipedia article on 16 April 2014, including a partial, condensed, edit history. The red color under the ''edit'' section indicates a deletion and green an insertion of text. The first few rows of the edit table show how models of global warming are put into doubt both through the edit activity and via the comments. Partial screenshot from Contropedia, 2015.

Measuring "undue weight''. The analysis of the related edit history and talk pages suggests that the publication of AR4 ignited controversial edit activity, as well as discussions around the wiki link "Intergovernmental Panel on Climate Change.'' The analysis also indicates that the report's publication affected other parts of the lead. In this section, Contropedia's historical view is used to showcase how the controversialness of issues may change over time, focusing on the substance of

the edits to the ''global warming'' article, before and after the release of AR4.

The most controversial issue in 2006 was ''list of scientists opposing global warming consensus'' while in 2007, when AR4 was released, the most controversial issue was ''scientists opposing the mainstream scientific assessment of global warming.'' While the content of both articles was in fact the same, its title changed from the former to the latter in early 2007. Figure 8 shows

Revision Edit User Edit summary Section Type Time

105516662 reverted by 106611280 Models referenced by the [[Intergovernmental Panel ori Climate Change]] (IPCC) predict lhat global temperatures may are likely to increase by 1. Raymond arritt update to reflect AR4 abstract s 2007-02-04 07:21:00

Figure 6. One edit in the history of the wiki link ''Intergovernmental Panel on Climate Change'' in the article on ''global warming'' Wikipedia 16 April 2014. Red indicates which word was removed and green which words were added. Small semantic changes matter. Partial screenshot from Contropedia, 2015.

Figure 7. POV template on the ''global warming'' Wikipedia article on 25 March 2007. Partial screenshot from Wikipedia contributors 2007a.

Figure 8. Detail of the dashboard view of the ''global warming'' Wikipedia article from 1 February 2006 to 1 February 2008. The second wiki link was used and controversial in 2006, whereas the first wiki link was present in the article throughout most of 2007. The names of both wiki links are struck through, as they do not appear in the article on 1 February 2008. Partial screenshot from Contropedia, 2015.

that the controversial edit activity increased after the publication of AR4.

The edit history of both articles suggests that the discussion revolved around the degree of support for AR4 in the academic community. The main dispute, as seen in the substantive edits table, evolved around the size of the group of scientists opposing global warming consensus (or mainstream assessment); it had been qualified as "a few,'' "relative few,'' "other," "a small number of,'' "many," "a number of,'' "about two dozen,'' "a small minority of,'' "a growing minority,'' and so on. Wikipedia style guidelines call such words "weasel words'' which are defined as "words and phrases aimed at creating an impression that something specific and meaningful has been said, when in fact only a vague or ambiguous claim has been communicated'' (Wikipedia contributors, 2014d). The guideline advises that vague terms should be rewritten, supported with reliable sources, or tagged with the appropriate weasel word template. The "undue weight'' guideline thus provides a way to not fall into the "trap" of providing a

false balance between viewpoints; the avoidance of "weasel words,'' furthermore, urges Wikipedians to be as concrete as possible by supporting claims with reliable sources.

When looking at the article "list of scientists opposing global warming consensus,'' it shows that Wikipedians seek to name and list those opposing the consensus of anthropogenic causes of global warming. They thus dealt with weasel words in the "global warming'' article by linking to an article detailing the vague qualifier. The article further divided the list into categories such as those that: "believe global warming is not occurring or has ceased,'' ''believe accuracy of IPCC climate projections is inadequate," ''believe global warming is primarily caused by natural processes,'' ''believe cause of global warming is unknown,'' and ''believe global warming will benefit human society'' (Wikipedia contributors, 2007e). It is worth noticing that within the article ''list of scientists opposing the mainstream scientific assessment of global warming''—its NPOV was disputed quite often because the list could never be complete (see Figure 9),

List of scientists opposing the mainstream scientific assessment of global warming m

From Wklpedla. the IrsB encyclopsdla

Trie neutrality of this article la disputed Relevant discussion may be lound en the talk page- Please not remove this message until the dispute

£ resolved. IMamh2014l

This is an incomplete fist that may never be aute to satisfy particular standards tor completeness. You can help by expanding it with entries that are reliabty source!

Figure 9. Disputed neutrality template on the Wikipedia article ''List of scientists opposing the mainstream scientific assessment of global warming.'' Partial screenshot. Source: Wikipedia contributors (2007e).

Discussion by the public and in popular media

Main articles: climate charge denial and global wanning controversy

The global warming controversy refers to a variety of disputes, substantially more pronounced in the popular media than in the scientific literature, regarding the nature, causes, and consequences of global warming. The disputed issues include the causes of increased especially since the mid-20th century,

whether this warming trend is unprecedented or within normal climatic variations, whether I^^^HH^^^^IBI^^^^HI^Hflflir end whether the increase is wholly or partially an artifact of poor measurements. Additional disputes concern estimates of climate sensitivity, predictions of additional wanting, and what the consequences of global warming will be.

From 19D0u£"1997 in the United States conservative think tanks mobilized to challenge the legitimacy of global warming as a social problem. They challenged the scientific evidence, argued that global warming will have benefits, and asserted that proposed solutions would do more harm than good-

Some people dispute aspects of climate charge science. Organizations such as the libertarian Competitive Enterprise Institute, conservative commentators, and some companies such as ExxonMobil have challenged IPCC climate change scenarios, funded scientists who disagree with the HM^I^I^MI. and provided their own projections of the economic cost ot stricter controls. Some fossil fuel companies have scaled back their efforts in recent years, or called for policies to reduce global warming.

Figure 10. ''Discussion by the public and in popular media.'' Section of the ''global warming'' Wikipedia article on 16 April 2014. The more controversial a wiki link, the redder it is. Climate change denial and the global warming controversy are described as a media discussion. Partial screenshot from Contropedia, 2015.

and because the name of the article had been changed several times. The article had been nominated for deletion a number of times and a name change had been suggested in these discussions. The title was relatively long and could be said to reflect that the controversy around it had not yet been resolved (Wikipedia contributors, 2010e: 11). The archived discussion threads (including the one ''title discussion'') from the beginning of 2007 very prominently featured AR4 (Wikipedia contributors, 2010c: 4). As the term ''consensus'' was considered controversial in the previous title, in the end the editors reach consensus over a name that referred to the ''mainstream scientific assessment.'' As one editor explained, "mainstream scientific assessment'' was preferred because it ''echoes the 'assessments' that have been formally done; for example TAR, AR4, U.S. National Assessment, and so on'' (Wikipedia contributors, 2010d: 4).

Returning to the problem of determining the size and weight of the different views, the tactic of Wikipedians was to link it to a dedicated article seeking to name and list the various scientists and scientific bodies in the various views supported with reliable sources, for example in the ''list of scientists that oppose the mainstream assessment of global warming.'' Linking to a dedicated article functions both as a

solution to dealing with weasel words, without adding too much detail in the main article, as well as a pressure valve for the ''global warming'' article by relocating controversy elsewhere. The analysis of the substantive edit history and talk pages in the year after AR4 suggests that the report itself was a ''reliable source'' in Wikipedia policy and helped to make the article more substantive with authoritative sources. While the global warming consensus became recognized as such, it sparked opposition to the authority of the IPCC by providing lists of those opposing the mainstream, also supported by reliable sources.

Global warming consensus? On 16 April 2014, at the time of the case study, the ''global warming'' article did not mention opposing views in the lead or links to the article listing them. Controversy about global warming had been moved to one of the bottom sections of the article titled ''discourse on global warming'' and included the subsections ''political discussion,'' ''scientific discussion,'' and ''discussion by the public and in popular media.'' Each subsection contained links to dedicated pages discussing the specific controversy or debate in more detail. It is most noticeable in reference to the introduction of this case study, that in this version of the Wikipedia article climate change denial and the

Figure 11. Partial dashboard view of the controversial wiki links in the ''global warming'' Wikipedia article between 16 April 2010 and 14 April 2014. In this period, for example, scientific opinion on climate change is more controversial than greenhouse gas. Partial screenshot from Contropedia, 2015.

global warming controversy were described as a media discussion, ignited by conservative think tanks and others (see Figure 10).

The link to the ''list of scientists opposing the mainstream assessment of global warming'' had however disappeared from the article text. The final edits to the link at the end of 2009 again redirected to the talk pages, where significant discussions were taking place about the neutrality of the article and about keeping balance in the scientific views on global warming. In reference to the link one of the editors argues in 2010:

I am seriously opposed to having that list of 'scientists' in the lede of this article. It has been added to the final section in an appropriate manner by another editor, and that should be the only appearance it makes. Bear in mind that the skeptics represent a tiny majority of scientists - so tiny, in fact, that their views should be considered to be on the fringe. Giving them a 'voice' in

the introduction would be a gross violation of WP:WEIGHT. (Wikipedia contributors, 2010b)

Again, ''undue weight'' is the key policy element referenced here. The gist of the consensus reached was that ''in order to be included, the 'sides', or more accurately, 'views' [...] must be shown to be significant'' (Wikipedia contributors, 2010b: 55). Around 2010 controversy on the ''global warming'' article seemed to have been resolved or at least cooled down, as indicated by the decrease in (controversial) edit activity. This is further supported by focusing the dashboard view of the ''global warming'' article to the last four years where the wiki links are hardly controversial (see Figure 11). Although the same controversial links still remained present in the top 10, it also shows that new issues had appeared and others had become more controversial. The decline of controversial edit activity

in the last four years of the article indicates that the controversy around this link to the list of opposing scientists had cooled down.

Wikipedians thus used a specific set of controversy defusing moves in accordance with Wikipedia's policy and guidelines. The device perspective allows us to identify how disputes were handled by using heavy editing and reverts and by taking into account how specific templates were used to indicate bias, weasel words, and NPOV disputes. While the introduction of AR4 at first led to discussion about its reliability, once it was established as a prominent and authoritative source, it was featured prominently in the lead and led to waning attention for the skeptics. Various policies and guidelines were invoked, such as the ones on verifiability (and reliability) and due weight, and all claims had to live up to those. Moreover, listing the size of the opposition in a separate article functioned both as a solution to dealing with weasel words, without adding too much detail in the main article, as well as a pressure valve for the ''global warming'' article by relocating controversy elsewhere.

Conclusion: Platform affordances and data practices

The case study in this article examined how Wikipedia's device culture—prescribed into the Wikimedia CMS, policies and guidelines, as well as the user interactions found in an article's edit history and talk pages—can be used to study the dynamics of knowledge production. The device perspective led us to take into account the performative qualities of Wikipedia and the cultures and practices of knowledge production established in negotiation with it. Approaching the online encyclopedia as a device, our analysis of the substance and trajectory of controversies in the article on global warming opens up a series of contributions.

With the leitmotif of ''following the medium'' (Rogers, 2013), we established Wikipedia's ''conditions of possibility'' (Fuller, 2008) for using it as a device that affords the continuous (re)negotiation and tweaking of knowledge. We argued that Wikipedia is a device that shapes a process of knowledge production that is never complete; inscribed into the Wikipedia platform is the notion that knowledge is unstable. The platform is designed to facilitate consensus about encyclopedic content through its guidelines, which are aimed at producing encyclopedic content in an open system in which everybody is allowed to edit. By studying the affor-dances of Wikipedia through an analysis of the affor-dances of its CMS, as well as an inspection of the processes for reaching consensus over disputed topics, we argue, one can easily surface the substance and dynamics of controversy in Wikipedia. The analysis of the negotiations between Wikipedians shows how

the device perspective links the medium specificity of the platform with the social arrangements and cultural practices that the platform incorporates and enables. For example, the case study underlines the prominent role of the ''due weight'' policy in resolving edit disputes. It also shows how the focus on wiki links may provide insight into the substance of controversies. Furthermore, it leads to the conclusion that the Wikipedia edit history and talk pages can help in identifying relevant controversies in the debates around global warming. The main contribution of using the device perspective when studying Wikipedia data, then, is that it can reveal the key matters in the controversy and allows one to map and chart which content within a page was controversial at what point in time, and to understand which specific controversy defusing moves are successful.

In the context of controversy research, the device culture perspective to Wikipedia not only provides a rich account of the practical application of editorial guidelines within the Wikipedia platform, but it also functions as a historical reference work for a detailed collection of which important scientific and media publications, as well as other events, play a role in the heating up, cooling down, displacement, and solution of controversies (see also Pentzold, 2009). The device perspective, we argue, thus allows one to recognize and employ the value of dispute on Wikipedia. The current form of the edit history and talk pages is such, however, that they are very difficult to analyze. Contropedia contributes to the use of Wikipedia as a rich tool for social researchers interested in the historical dynamics of any controversy with a significant number of edits on Wikipedia, as it delivers only substantive edits, recognizes the role of wiki links as matters of concern, and highlights, counts, and weighs substantive, disagreeing, edits to sentences containing these wiki links. Aligning the device culture's medium-specific characteristics productively with controversy mapping led us to filter out vandalism and maintenance edits. The resulting collections of edits and talk page comments then allow for two analytic steps: first, to study various controversies within an article, and second, to discern the entangled roles of policies and guidelines, CMS and editors in dealing with and resolving controversies.

Although the case study is confined to the article about global warming on Wikipedia, we propose that the device perspective can also be applied to other platforms. The device perspective brings together modes of analysis common in platform studies and the related field of software studies, such as analyzing interfaces and platform documentation, with an approach that analyses digital data to study social arrangements and cultural practices. The approach allows for the recognition of how specific practices and uses negotiate with

the affordances of a platform and in doing so are instrumental in shaping the data being produced on platforms. As such the device perspective provides a possible roadmap for critical data studies that start from the assumption that data is always already ''cooked'' (Gitelman, 2013). We argue that the study of online data necessitates taking into account both the affordances of platforms as well as their use cultures and data practices in order to emphasize the conditions of possibility of the data under study, i.e. those generated through the affordances of a specific device, as well as the performativity of the user and the actual data practices that follow from it.

In the case study on Wikipedia, we focused on how Wikipedia allows for the creation of encyclopedic content by managing dispute. Other platforms structure activity differently; think for example about how trending topics, promoted content, and popular videos bring together a complex arrangement of affordances, practices, uses, and algorithmic operations, which we propose to study with the notion of device cultures.


We would like to thank the reviewers and editors from BD&S for their useful comments. We would also like to thank our colleagues with whom we jointly developed Contropedia, which we used for our empirical analysis.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.


The author(s) received no financial support for the research, authorship, and/or publication of this article.

1. The term affordance stems from psychology (Gibson, 1977), was picked up by Human-Computer Interface design (e.g., Preece et al., 1994) and product design (Norman, 2002), and was repurposed by critical studies into the ideal users and norms that are designed into software (Fuller, 2003; Stanfill, 2015).

2. According to its dictionary definition the term device has multiple meanings and is used in myriad contexts, referring to objects designed for a specific purpose, such as gadgets, tools, and bombs, as well as methods, such as tactics, plans, stratagems, and designs (Device, 2016).

3. Although the platform is relatively open and the available data comprehensive, not all communication about an article or policy necessarily takes place on the Wikipedia platform, and there are some documented instances where content was removed from Wikipedia without a corresponding log entry in the MediaWiki software (O'Neil, 2009).

4. The specific politics of these culture of openness have been challenged and unpicked by Nathaniel Tkacz (2014).

5. On other platforms too, such a coproduction of unanticipated features and affordances can be observed. On Twitter, for example, users have started using #hashtags to group discussions, and @mentions to address other users before these were incorporated in the platform architecture (see e.g., Parker, 2011).

6. Note that the specific hierarchy and permissions of users may vary between languages.

7. We developed Contropedia in collaboration with Density Design (Milan, Italy), Eurecat (Barcelona, Spain), and Sciences-Po (Paris, France). It is freely available via

8. Controversy according to Wikipedia's ''list of controversial issues'' concerns articles or topics that are subject to edit warring and tend to be biased or have been the subject of NPOV disputes (or will probably be in future) (Wikipedia contributors, 2014c).

9. In other research too, conflict and coordination on Wikipedia has been identified and visualized (Brandes and Lerner, 2008; Ekstrand and Riedl, 2009; Kittur et al., 2007; Suh et al., 2007; Sumi et al., 2011; Yasseri et al., 2012). Most of these studies employ reverts as the prime mechanism with which to detect whether an article is controversial (see, e.g., Kittur et al., 2007; Suh et al., 2007; Yasseri et al., 2012) and are primarily focused on the social dynamics between editors. Only a few considered the (types of) content of controversial edits (Rad and Barbosa, 2012; Viegas et al., 2007), as is the aim here.

10. To detect vandalism our algorithm identifies and discards revisions for which the edit comment contains the string ''vandal,'' if the username making the revert belongs to one of the known vandalism bots, or when an edit is reverted within 60 s. Edits marked as WP:AES are also discarded (Wikipedia contributors, 2014a). Note that repeated changes against consensus and edit warring are not regarded as vandalism and those reverts will thus not be marked as such.

11. Bao et al. (2012) have similarly regarded the links within a specific article as indicative of the subject composition of an article. Through the analysis of common, and unique, links of different language versions of the same article they were able to investigate differing cultural understandings of a topic. Similarly, Hecht and Gergle (2009) demonstrated on the basis of wiki links that language versions of Wikipedia are self-focused. While in this article we focus on the analytic affordances of internal links, in future work we will extend this to other wiki links such as templates and references.

12. For a more elaborate technical description of how Contropedia functions, see Borra et al. (2015).

13. This Wikipedia policy is part of the NPOV policy and requires that each article ''fairly represents all significant viewpoints that have been published by reliable sources, in proportion to the prominence of each viewpoint in the published, reliable sources'' (Wikipedia contributors, 2014e).


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