The Digital Architectures of Social Media: Comparing Political Campaigning on Facebook, Twitter, Instagram, and Snapchat in the 2016 U.S. Election

The present study argues that political communication on social media is mediated by a platform's digital architecture, defined as the technical protocols that enable, constrain, and shape user behavior in a virtual space. A framework for understanding digital architectures is introduced, and four platforms (Facebook, Twitter, Instagram, and Snapchat) are compared along the typology. Using the 2016 US election as a case, interviews with three Republican digital strategists are combined with social media data to qualify the studyies theoretical claim that a platform's network structure, functionality, algorithmic filtering, and datafication model affect political campaign strategy on social media

Introduction: On Not Taking the Hyperlink for Granted

Book description: Links are among the most basic—and most unexamined—features of online life. Bringing together a prominent array of thinkers from industry and the academy, The Hyperlinked Society addresses a provocative series of questions about the ways in which hyperlinks organize behavior online. How do media producers\u27 considerations of links change the way they approach their work, and how do these considerations in turn affect the ways that audiences consume news and entertainment? What role do economic and political considerations play in information producers\u27 creation of links? How do links shape the size and scope of the public sphere in the digital age? Are hyperlinks bridging mechanisms that encourage people to see beyond their personal beliefs to a broader and more diverse world? Or do they simply reinforce existing bonds by encouraging people to ignore social and political perspectives that conflict with their existing interests and beliefs? This pathbreaking collection of essays will be valuable to anyone interested in the now taken for granted connections that structure communication, commerce, and civic discourse in the world of digital media. - See more at: http://www.press.umich.edu/297297/hyperlinked_society#sthash.APFUH8ip.dpu

WP2 Report from the ECHO IT Days

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Processing Structured Hypermedia : A Matter of Style

With the introduction of the World Wide Web in the early nineties, hypermedia has become the uniform interface to the wide variety of information sources available over the Internet. The full potential of the Web, however, can only be realized by building on the strengths of its underlying research fields. This book describes the areas of hypertext, multimedia, electronic publishing and the World Wide Web and points out fundamental similarities and differences in approaches towards the processing of information. It gives an overview of the dominant models and tools developed in these fields and describes the key interrelationships and mutual incompatibilities. In addition to a formal specification of a selection of these models, the book discusses the impact of the models described on the software architectures that have been developed for processing hypermedia documents. Two example hypermedia architectures are described in more detail: the DejaVu object-oriented hypermedia framework, developed at the VU, and CWI's Berlage environment for time-based hypermedia document transformations

Generating Method Documentation Using Concrete Values from Executions

There exist multiple automated approaches of source code documentation generation. They often describe methods in abstract terms, using the words contained in the static source code or code excerpts from repositories. In this paper, we introduce DynamiDoc - a simple yet effective automated documentation approach based on dynamic analysis. It traces the program being executed and records string representations of concrete argument values, a return value, and a target object state before and after each method execution. Then for every concerned method, it generates documentation sentences containing examples, such as "When called on [3, 1.2] with element = 3, the object changed to [1.2]". A qualitative evaluation is performed, listing advantages and shortcomings of the approach

Web interaction environments : characterising Web accessibility at the large

Tese de doutoramento, Informática (Engenharia Informática), Universidade de Lisboa, Faculdade de Ciências, 2012Accessibility quality on the Web is essential for providing a good Web experience to people with disabilities. The existence of virtual ramps aid these users grasping and interacting withWeb content, just like the experience of those who are unimpaired. However, more often than not, Web pages impose accessibility barriers, usually centred on the unavailability of tailored content to specific perceptual abilities (e.g., textual description of images, enabling grasping information with assistive technologies), as well as on proper HTML structural elements that adequate the semantics of a Web page. When evaluating the accessibility quality of Web pages, the resulting analysis is often focused on a small sample set (e.g., a single Web page or a selection of pages from a Web site). While this kind of analysis gets the gist of accessibility quality, it misses the big picture on the overall accessibility quality of the Web. This thesis addresses the challenge of observing accessibility phenomena on the Web, through the experimental evaluation of large collections of Web pages. This resulted on new findings about the accessibility quality of the Web, such as its correlation with HTML element count, and the erroneous perception of accessibility quality by developers. Small-scale experiments have been verified also at large scale, such as the correlation between the usage of HTML templates and accessibility quality. Based on the challenges raised by the experimental evaluation, this thesis proposes a novel approach for large scale Web accessibility evaluation based on Linked Data, as well as the establishment of metrics to assess the truthfulness and coverage of automated evaluation methods.A qualidade da acessibilidade é um factor crucial para as pessoas com deficiências terem uma boa experiência de interacção com a Web.A qualidade da acessibilidade é um factor crucial para as pessoas com deficiências terem uma boa experiência de interacção com a Web. A existência de rampas virtuais ajuda estas pessoas a compreender e interagir com conteúdos Web, a par do que o utilizador comum já experiencia. Porém, a maioria das páginas Web ainda contêm barreiras à acessibilidade. Estas barreiras centram-se normalmente na indisponibilidade de conteúdos perceptíveis por diferentes tipos de capacidades (e.g., descrições textuais de imagens), bem como no uso incorrecto de elementos HTML de acordo com a semântica de uma página Web. Nos dias de hoje, a avaliação da qualidade de acessibilidade de páginas Web é ainda efectuada em pequena escala (e.g., uma página Web ou, no melhor caso, um conjunto de páginas representativas de um sítio Web). Apesar deste tipo de avaliações resultarem na compreensão de alguns fenómenos do estado da acessibilidade na Web, ainda não se sabe qual o seu impacto em larga escala. Esta tese discute os principais desafios na observação da acessibilidade da Web, tendo por base um conjunto de avaliações experimentais de colecções de grande dimensão de páginas Web. Destes estudos destacam-se as seguintes contribuições e resultados:a diferença drástica na interpretação dos avisos resultantes de avaliações de acessibilidade Web: um dos resultados principais da avaliação experimental em larga escala destaca a diferença na interpretação dos avisos (warnings) da aplicação de técnicas da norma WCAG, onde a interpretação optimista (i.e., a visão da maioria dos criadores de páginas Web) se distancia amplamente da interpretação conservadora (onde os avisos são interpretados como erros); a correlação entre a qualidade da acessibilidade de uma página Web e a sua complexidade: este mesmo estudo de larga escala revelou uma correlação entre a complexidade de uma página Web (no que diz respeito ao número de elementos HTML que contém) e a qualidade da acessibilidade. Quanto menor a complexidade de uma página Web, mais certa se torna a alta qualidade da acessibilidade dessa página; o benefício do uso de templates e sistemas de gestão de conteúdos na melhoria da acessibilidade de páginas Web: em ambos os estudos experimentais de acessibilidade foi detectada uma correlação entre a qualidade de acessibilidade das páginas Web e o uso de templates e sistemas de gestão de conteúdo. Esta propriedade foi verificada quer em pequena escala (sobre uma colecção de páginas Web da Wikipedia), quer em larga escala; o incumprimento das regras mais elementares e mais conhecidas da acessibilidade: estes estudos experimentais permitiram também verificar que, apesar de toda a envagelização e educação sobre as questões de acessibilidade na Web, a maioria das regras de acessibilidade são incessantemente quebradas pela maioria das páginas Web.Esta problemática verifica-se, em particular, nas regras de cumprimento de acessibilidade mais conhecidas, tal como por exemplo a disponibilidade de textos alternativos a conteúdos multimédia. Com base nestas experiências e resultados, esta tese apresenta um novo modelo de estudo da acessibilidade na Web, tendo por base o ciclo de estudos da Web em larga escala. Deste modelo resultaram as seguintes contribuições: um modelo para a avaliação distribuída de acessibilidade Web, baseado em propriedades tecnológicas e topológicas: foi concebido um modelo de avaliação de acessibilidade Web que permite a concepção de sistemas de avaliação com base em propriedades tecnológicas e topológicas. Este modelo possibilita, entre outras características, o estudo da cobertura de plataformas e avaliadores de acessibilidade, bem como da sua aplicação em larga escala; uma extensão às linguagens e modelos EARL e Linked Data, bem como um conjunto de definições para extrair informação destes: este modelo de avaliação de acessibilidade Web foi sustentado também pela sua concretização em linguagens e modelos já existentes para o estudo de acessibilidade (EARL) e da Web em larga escala (Linked Data), permitindo assim a sua validação; definição dos limites da avaliação de acessibilidade Web: por fim, este modelo de avaliação de acessibilidade permitiu também delinear uma metodologia de meta-avaliação da acessibilidade, na qual se poderão enquadrar as propriedades dos avaliadores de acessibilidade existentes. Todas estas contribuições resultaram também num conjunto de publicações científicas, das quais se destacam: Rui Lopes and Luís Carriço, A Web Science Perspective of Web Accessibility, in submission for the ACM Transactions on Accessible Computing (TACCESS), ACM, 2011; Rui Lopes and Luís Carriço, Macroscopic Characterisations of Web Accessibility, New Review of Hypermedia and Multimedia – Special Issue on Web Accessibility. Taylor & Francis, 2010; Rui Lopes, Karel Van Isacker and Luís Carriço, Redefining Assumptions: Accessibility and Its Stakeholders, The 12th International Conference on Computers Helping People with Special Needs (ICCHP), Vienna, Austria, 14-16 July 2010; Rui Lopes, Daniel Gomes and Luís Carriço, Web Not For All: A Large Scale Study of Web Accessibility, W4A: 7th ACM International Cross-Disciplinary Conference on Web Accessibility, Raleigh, North Carolina, USA, 26-27 April 2010; Rui Lopes, Konstantinos Votis, Luís Carriço, Dimitrios Tzovaras, and Spiridon Likothanassis, The Semantics of Personalised Web Accessibility Assessment, 25th Annual ACM Symposium on Applied Computing (SAC), Sierre, Switzerland, 22-26 March, 2010 Konstantinos Votis, Rui Lopes, Dimitrios Tzovaras, Luís Carriço and Spiridon Likothanassis, A Semantic Accessibility Assessment Environment for Design and Development for the Web, HCI International 2009 (HCII 2009), San Diego, California, USA, 19-24 July 2009 Rui Lopes and Luís Carriço, On the Gap Between Automated and In-Vivo Evaluations of Web Accessibility, HCI International 2009 (HCII 2009), San Diego, California, USA, 19-24 July 2009; Rui Lopes, Konstantinos Votis, Luís Carriço, Spiridon Likothanassis and Dimitrios Tzovaras, Towards the Universal Semantic Assessment of Accessibility, 24th Annual ACM Symposium on Applied Computing (SAC),Waikiki Beach, Honolulu, Hawaii, USA, 8-12 March 2009; Rui Lopes and Luís Carriço, Querying Web Accessibility Knowledge from Web Graphs, Handbook of Research on Social Dimensions of Semantic Technologies, IGI Global, 2009; Rui Lopes, Konstantinos Votis, Luís Carriço, Spiridon Likothanassis and Dimitrios Tzovaras, A Service Oriented Ontological Framework for the Semantic Validation of Web Accessibility, Handbook of Research on Social Dimensions of Semantic Technologies, IGI Global, 2009; Rui Lopes and Luís Carriço, On the Credibility of Wikipedia: an Accessibility Perspective, Second Workshop on Information Credibility on the Web (WICOW 2008), Napa Valley, California, USA, 2008; Rui Lopes, Luís Carriço, A Model for Universal Usability on the Web, WSW 2008: Web Science Workshop, Beijing, China, 22 April 2008; Rui Lopes, Luís Carriço, The Impact of Accessibility Assessment in Macro Scale Universal Usability Studies of the Web, W4A: 5th ACM International Cross-Disciplinary Conference on Web Accessibility, Beijing, China, 21-22 April 2008. Best paper award; Rui Lopes, Luís Carriço, Modelling Web Accessibility for Rich Document Production, Journal on Access Services 6 (1-2), Routledge, Taylor & Francis Group, 2009; Rui Lopes, Luís Carriço, Leveraging Rich Accessible Documents on the Web, W4A: 4th ACM International Cross-Disciplinary Conference on Web Accessibility, Banff, Canada, 7-8 May 2007.Fundação para a Ciência e a Tecnologia (FCT, SFRH/BD/29150/2006

The Structure of Federal eGovernment: Using hyperlinks to analyze the .gov domain

This paper uses the hyperlink structure of federal web sites within the .gov domain to answer two research questions: to what degree does the online structure of the federal government mirror its offline hierarchy, and to what degree does the .gov web graph mirror the greater WWW graph. Findings of subgraph link analysis and Krackhardt’s graph theoretical dimensions of hierarchy analysis demonstrate clear hierarchy within the .gov domain, but also suggest great discrepancies in the linking patterns of different government departments. Structural analysis suggests that the .gov web graph is indeed a fractal leaf of the greater WWW graph

On the discovery of social roles in large scale social systems

The social role of a participant in a social system is a label conceptualizing the circumstances under which she interacts within it. They may be used as a theoretical tool that explains why and how users participate in an online social system. Social role analysis also serves practical purposes, such as reducing the structure of complex systems to rela- tionships among roles rather than alters, and enabling a comparison of social systems that emerge in similar contexts. This article presents a data-driven approach for the discovery of social roles in large scale social systems. Motivated by an analysis of the present art, the method discovers roles by the conditional triad censuses of user ego-networks, which is a promising tool because they capture the degree to which basic social forces push upon a user to interact with others. Clusters of censuses, inferred from samples of large scale network carefully chosen to preserve local structural prop- erties, define the social roles. The promise of the method is demonstrated by discussing and discovering the roles that emerge in both Facebook and Wikipedia. The article con- cludes with a discussion of the challenges and future opportunities in the discovery of social roles in large social systems