Tommaso Venturini

ForceAtlas2, a Continuous Graph Layout Algorithm for Handy Network Visualization Designed for the Gephi Software

Gephi is a network visualization software used in various disciplines (social network analysis, biology, genomics…). One of its key features is the ability to display the spatialization process, aiming at transforming the network into a map, and ForceAtlas2 is its default layout algorithm. The latter is developed by the Gephi team as an all-around solution to Gephi users’ typical networks (scale-free, 10 to 10,000 nodes). We present here for the first time its functioning and settings. ForceAtlas2 is a force-directed layout close to other algorithms used for network spatialization. We do not claim a theoretical advance but an attempt to integrate different techniques such as the Barnes Hut simulation, degree-dependent repulsive force, and local and global adaptive temperatures. It is designed for the Gephi user experience (it is a continuous algorithm), and we explain which constraints it implies. The algorithm benefits from much feedback and is developed in order to provide many possibilities through its settings. We lay out its complete functioning for the users who need a precise understanding of its behaviour, from the formulas to graphic illustration of the result. We propose a benchmark for our compromise between performance and quality. We also explain why we integrated its various features and discuss our design choices.

Diving in magma: how to explore controversies with actor-network theory

The cartography of controversies is a set of techniques to explore and visualize issues. It was developed by Bruno Latour as a didactic version of Actor-Network Theory to train college students in the investigation of contemporary socio-technical debate. The scope and interest of such cartography, however, exceed its didactic origin. Adopted and developed in several universities in Europe and the US, the cartography of controversies is today a full research method, though, unfortunately, not a much documented one. To fill this lack of documentation, we draw on our experience as Latour’s teaching assistant, to introduce some of the main techniques of the social cartographer toolkit. In particular, in these pages we will focus on exploration, leaving the discussion of visualization tools to a further paper.

Three maps and three misunderstandings: A digital mapping of climate diplomacy

This article proposes an original analysis of the international debate on climate change through the use of digital methods. Its originality is twofold. First, it examines a corpus of reports covering 18 years of international climate negotiations, a dataset never explored before through digital techniques. This corpus is particularly interesting because it provides the most consistent and detailed reporting of the negotiations of the United Nations Framework Convention on Climate Change. Second, in this paper we test an original approach to text analysis that combines automatic extractions and manual selection of the key issue-terms. Through this mixed approach, we tried to obtain relevant findings without imposing them on our corpus. The originality of our corpus and of our approach encouraged us to question some of the habits of digital research and confront three common misunderstandings about digital methods that we discuss in the first part of the article (section ‘Three misunderstandings on digital methods in social sciences’). In addition to reflecting on methodology, however, we also wanted to offer some substantial contribution to the understanding of UN-framed climate diplomacy. In the second part of the article (section ‘Three maps on climate negotiations’) we will therefore introduce some of the preliminary results of our analysis. By discussing three visualizations, we will analyze the thematic articulation of the climatic negotiations, the rise and fall of these themes over time and the visibility of different countries in the debate.

Building on faults: How to represent controversies with digital methods

In a previous article in this journal, I introduced Bruno Latour’s cartography of controversies and I discussed half of it, namely how to observe techno-scientific controversies. In this article I will concentrate on the remaining half: how to represent the complexity of social debates in a legible form. In my previous paper, we learnt how to explore the richness of collective existence through Actor-Network Theory. In this one, I will discuss how to render such complexity through an original visualization device: the controversy-website. Capitalizing on the potential of digital technologies, the controversy-website has been developed as a multilayered toolkit to trace and aggregate information on public debates.

Societal Controversies in Wikipedia Articles

Collaborative content creation inevitably reaches situations where different points of view lead to conflict. We focus on Wikipedia, the free encyclopedia anyone may edit, where disputes about content in controversial articles often reflect larger societal debates. While Wikipedia has a public edit history and discussion section for every article, the substance of these sections is difficult to phantom for Wikipedia users interested in the development of an article and in locating which topics were most controversial. In this paper we present Contropedia, a tool that augments Wikipedia articles and gives insight into the development of controversial topics. Contropedia uses an efficient language agnostic measure based on the edit history that focuses on wiki links to easily identify which topics within a Wikipedia article have been most controversial and when.

Does television reflect the evolution of scientific knowledge? The case of attention deficit hyperactivity disorder coverage on French television:

Biomedical findings mature from uncertain observations to validated facts. Although subsequent studies often refute initial appealing findings, newspapers privilege the latter and often fail to cover refutations. Thus, biomedical knowledge and media reporting may diverge with time. Here we investigated how French television reported on three scientific questions relative to attention deficit hyperactivity disorder (ADHD) from 1995 to 2010: i) is ADHD mainly genetic in origin, ii) does methylphenidate treatment decrease the risk of academic underachievement, and iii) are brain imaging techniques able to reveal ADHD in individual patients? Although scientific evidence regarding these questions has evolved during these 16 years, we observed that nine out of ten TV programs broadcast between 2007 and 2010 still expressed only opinions against the current scientific consensuses. The failure of TV programs to reflect the evolution of the scientific knowledge might be related to a biased selection of medical experts.

Intangible cultural heritage webs: Comparing national networks with digital methods

The 2003 United Nations Educational, Scientific and Cultural Organization (UNESCO) Convention for the safeguard of intangible cultural heritage (ICH) is addressed to the States and assigns them several tasks. However, no State can accomplish all these tasks without mobilizing a wide network of institutions, associations, and individuals. The national ICH policies intersect, overlap, and often transform the existing relationships among these actors. This study aims at comparing several national networks (France, Italy, and Switzerland) involved in the implementation of the 2003 UNESCO Convention to highlight national trends and specificities. The analysis has employed an innovative methodology based on digital methods and is aimed at exploring the landscapes of websites dedicated to the intangible heritage. By analyzing the hyperlinking strategies of ICH actors, we have identified the specific web topology of each nation, showing which actors are central and peripheral, whether clusters or cliques are formed, and who plays the roles of authority and hub.

Fill in the Gap. a New Alliance for Social and Natural Sciences

In the last few years, electronic media brought a revolution in the traceability of social phenomena. As particles in a bubble chamber, social trajectories leave digital trails that can be analyzed to gain a deeper understanding of collective life. To make sense of these traces a renewed collaboration between social and natural scientists is needed. In this paper, we claim that current research strategies based on micro-macro models are unfit to unfold the complexity of collective existence and that the priority should instead be the development of new formal tools to exploit the richness of digital data.

Contropedia - the analysis and visualization of controversies in Wikipedia articles

Collaborative content creation inevitably reaches situations where different points of view lead to conflict. In Wikipedia, one of the most prominent examples of collaboration online, conflict is mediated by both policy and software, and conflicts often reflect larger societal debates. Contropedia is a platform for the analysis and visualization of such controversies in Wikipedia. Controversy metrics are extracted from activity streams generated by edits to, and discussions about, individual articles and groups of related articles. An articles revision history and its corresponding discussion pages constitute two parallel streams of user interactions that, taken together, fully describe the process of the collaborative creation of an article. Our proposed platform, Contropedia, builds on state of the art techniques and extends current metrics for the analysis of both edit and discussion activity and visualizes these both as a layer on top of Wikipedia articles as well as a dashboard view presenting additional analytics. Furthermore, the combination of these two approaches allows for a deeper understanding of the substance, composition, actor alignment, trajectory and liveliness of controversies on Wikipedia. Our research aims to provide a better understanding of socio-technical phenomena that take place on the web and to equip citizens with tools to fully deploy the complexity of controversies. Contropedia is useful for the general public as well as user groups with specific interests such as scientists, students, data journalists, decision makers and media communicators. Contropedia can be found at http://contropedia.net.

Drivers for emerging issues in animal and plant health

Abstract The history of agriculture includes many animal and plant disease events that have had major consequences for the sector, as well as for humans. At the same time, human activities beyond agriculture have often driven the emergence of diseases. The more that humans expand the footprint of the global population, encroach into natural habitats, alter these habitats to extract resources and intensify food production, as well as move animals, people and commodities along with the pathogens they carry, the greater the potential for pathogens and pests to spread and for infection to emerge or re‐emerge. While essential to human well‐being, producing food also plays a major role in disease dynamics. The risk of emergence of pests and pathogens has increased as a consequence of global changes in the way food is produced, moved and consumed. Climate change is likely to increase pressure on the availability of food and provide newly suitable conditions for invasive pests and pathogens. Human population displacements due to economic, political and humanitarian crises represent another set of potential drivers for emerging issues. The overlapping drivers of plant, animal and human disease emergence and environmental changes point towards the concept of ‘One Health’. This paradigm underlines the urgent need to understand the influence of human behaviour and incorporate this understanding into our approach to emerging risks. For this, we face two major challenges. One is cultural; the second is methodological. We have to look at systems not under the narrow view of specific hazards but with a wider approach to system dynamics, and consider a broad spectrum of potential outcomes in terms of risk. In addition, we have to make sense of the vast amounts of data that are available in the modern age. This paper aims to help in preparing for the cultural and methodological shifts needed in our approach to emerging risks.