Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia
Time and place:
The Conference on Hypertext and Hypermedia brings together scholars, researchers, and practitioners from diverse disciplines to consider the form, role and impact of hypertext and hypermedia in a forum of discussion of ideas, design and use of hypertext and hypermedia in a variety of domains. The conference also considers the transformative power of hypermedia and its ability to alter the way we read, write, argue, work, exchange information and entertain ourselves.
The following articles are from "Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia":
Huberman, Bernardo (2008): Social dynamics in the age of the web. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 1-2. Available online
The past decade has witnessed a momentous transformation in the way people interact and exchange information. Content is now coactively produced, shared, classified, and rated on the Web by millions of people, while attention has become an ephemeral and valuable resource that everyone seeks to acquire. This talk will describe our research on the interplay between popularity, novelty and collective attention in the Web, as well as a study of the dynamics of online opinion formation.
Stefanone, Michael A., Lackaff, Derek and Rosen, Devan (2008): We're all stars now: reality television, web 2.0, and mediated identities. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 107-112. Available online
Social cognitive theory suggests a likely relationship between the rising popularity of both reality television and social networking sites. This research utilized a survey (N=456) of young adults to determine the extent to which reality television consumption explains user behavior in the context of social network sites. Results show a consistent relationship between reality television consumption on the length of time spent logged on to these sites, the size of user's networks, the proportion of friends not actually met face to face, and photo sharing frequency while controlling for age, gender and education. Other categories of television viewing like news, fiction, and educational programming were not related to user's online behavior.
Kolb, David A. (2008): Making revisions hyper-visible. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 113-116. Available online
What should a revised edition of a hypertext be? How might revising a hypertext differ from reissuing a printed book? This essay suggests a revision process that is self-reflexive and explicitly made visible, taking advantage of the ability of hypertext to expand the "margins" of a document in new directions. Where the issues are complex enough, the process of revision should be part of what is presented, not just a machine rumbling in the background that issues in a separate product.
Kolak, Okan and Schilit, Bill N. (2008): Generating links by mining quotations. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 117-126. Available online
Scanning books, magazines, and newspapers has become a widespread activity because people believe that much of the worlds information still resides off-line. In general after works are scanned they are indexed for search and processed to add links. This paper describes a new approach to automatically add links by mining popularly quoted passages. Our technique connects elements that are semantically rich, so strong relations are made. Moreover, link targets point within a work, facilitating navigation. This paper makes three contributions. We describe a scalable algorithm for mining repeated word sequences from extremely large text corpora. Second, we present techniques that filter and rank the repeated sequences for quotations. Third, we present a new user interface for navigating across and within works in the collection using quotation links. Our system has been run on a digital library of over 1 million books and has been used by thousands of people.
Lakkaraju, Praveen, Gauch, Susan and Speretta, Mirco (2008): Document similarity based on concept tree distance. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 127-132. Available online
The Web is quickly moving from the era of search engines to the era of discovery engines. Whereas search engines help you find information you are looking for, discovery engines help you find things that you never knew existed. A common discovery technique is to automatically identify and display objects similar to ones previously viewed by the user. Core to this approach is an accurate method to identify similar documents. In this paper, we present a new approach to identifying similar documents based on a conceptual tree-similarity measure. We represent each document as a concept tree using the concept associations obtained from a classifier. Then, we make employ a tree-similarity measure based on a tree edit distance to compute similarities between concept trees. Experiments on documents from the CiteSeer collection showed that our algorithm performed significantly better than document similarity based on the traditional vector space model.
Viewed collectively, the sum of all blog entries recorded to date (usually referred to as the blogosphere) represents a prodigiously rich collection of commentary and opinion, a dizzying mixture of fact and speculation, subjective opinion and objective data. This paper introduces a hypermedia authoring tool intended to simplify the process of navigating this chaotic environment. The tool works by adding additional hyperlinks to blogs, links which connect blog entries addressing similar topics. These hyperlinks are generated by an algorithm that uses statistical language modeling and graph based analysis to exploit the implicit associative structure of the blogosphere. An evaluative exercise, centred upon the unsupervised labeling of blog articles, confirms the effectiveness of this approach.
Lee, Hyun Chul, Borodin, Allan and Goldsmith, Leslie (2008): Extracting and ranking viral communities using seeds and content similarity. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 139-148. Available online
We study the community extraction problem within the context of networks of blogs and forums. When starting from a small set of known seed nodes, we argue that the use of content information (beyond explicit link information) plays an essential role in the identification of the relevant community. Our approach lends itself to a new and insightful ranking scheme for members of the extracted community and an efficient algorithm for inflating/deflating the extracted community. Using a considerably large commercial data set of blog and forum sites, we provide experimental evidence to demonstrate the utility, efficiency, and stability of our methods.
Markines, Benjamin, Roinestad, Heather and Menczer, Filippo (2008): Efficient assembly of social semantic networks. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 149-156. Available online
Social bookmarks allow Web users to actively annotate individual Web resources. Researchers are exploring the use of these annotations to create implicit links between online resources. We define an implicit link as a relationship between two online resources established by the Web community. An individual may create or reinforce a relationship between two resources by applying a common tag or organizing them in a common folder. This has led to the exploration of techniques for building networks of resources, categories, and people using the social annotations. In order for these techniques to move from the lab to the real world, efficient building and maintenance of these potentially large networks remains a major obstacle. Methods for assembling and indexing these large networks will allow researchers to run more rigorous assessments of their proposed techniques. Toward this goal we explore an approach from the sparse matrix literature and apply it to our system, GiveALink.org. We also investigate distributing the assembly, allowing us to grow the network with the body of resources, annotations, and users. Dividing the network is effective for assembling a global network where the implicit links are dependent on global properties. Additionally, we explore alternative implicit link measures that remove global dependencies and thus allow for the global network to be assembled incrementally, as each participant makes independent contributions. Finally we evaluate three scalable similarity measures, two of which require a revision of the data model underlying our social annotations.
Albertsen, Johannes and Bouvin, Niels Olof (2008): User defined structural searches in mediawiki. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 15-20. Available online
Wikipedia has been the poster child of user contributed content using the space of MediaWiki as the canvas on which to write. While well suited for authoring simple hypermedia documents, MediaWiki does not lend itself easily to let the author create dynamically assembled documents, or create pages that monitor other pages. While it is possible to create such "special" pages, it requires PHP coding and thus administrative rights to the MediaWiki server. We present in this paper work on a structural query language (MediaWiki Query Language -- MWQL) to allow users to add dynamically evaluated searches to ordinary wiki-pages.
Krause, Beate, Jäschke, Robert, Hotho, Andreas and Stumme, Gerd (2008): Logsonomy -- social information retrieval with logdata. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 157-166. Available online
Social bookmarking systems constitute an established part of the Web 2.0. In such systems users describe bookmarks by keywords called tags. The structure behind these social systems, called folksonomies, can be viewed as a tripartite hypergraph of user, tag and resource nodes. This underlying network shows specific structural properties that explain its growth and the possibility of serendipitous exploration. Today's search engines represent the gateway to retrieve information from the World Wide Web. Short queries typically consisting of two to three words describe a user's information need. In response to the displayed results of the search engine, users click on the links of the result page as they expect the answer to be of relevance. This clickdata can be represented as a folksonomy in which queries are descriptions of clicked URLs. The resulting network structure, which we will term logsonomy is very similar to the one of folksonomies. In order to find out about its properties, we analyze the topological characteristics of the tripartite hypergraph of queries, users and bookmarks on a large snapshot of del.icio.us and on query logs of two large search engines. All of the three datasets show small world properties. The tagging behavior of users, which is explained by preferential attachment of the tags in social bookmark systems, is reflected in the distribution of single query words in search engines. We can conclude that the clicking behaviour of search engine users based on the displayed search results and the tagging behaviour of social bookmarking users is driven by similar dynamics.
Lawless, Séamus, Hederman, Lucy and Wade, Vincent (2008): Enhancing access to open corpus educational content: learning in the wild. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 167-174. Available online
The World Wide Web (WWW) provides access to a vast array of interconnected educational content on almost every subject imaginable. A great deal of this content is ideal for incorporation into personalised eLearning experiences. However the discovery, harvesting and incorporation of appropriate educational material have proven to be complex and arduous tasks. Traditional educational hypertext systems are based upon the generation of links and anchors between content objects . However the dynamic incorporation of open corpus educational content in eLearning requires the generation of a relationship between educational concepts and the hypertext documents. One approach to create this overlay between concept and content is to use a Mindmap interface to allow learners to explore and associate hypertext content with knowledge maps of their own creation. This paper presents the Open Corpus Content Service (OCCS), a framework that uses the hypertext structure of the WWW to provide methods of educational content discovery and harvesting. The OCCS semantically examines linked content on both the WWW and in digital content repositories, and creates concept specific caches of content. The paper also introduces U-CREATe, a novel user-driven Mindmap interface for supporting the exploration and assembly of content cached by the OCCS, in a pedagogically meaningful manner. The combination of these systems benefits both the educator and learner, empowering the learner through ownership of the educational experience and allowing the educator to focus on the pedagogical design of educational offerings rather than content authoring.
Hansen, Frank Allan and Grønbæk, Kaj (2008): Social web applications in the city: a lightweight infrastructure for urban computing. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 175-180. Available online
In this paper, we describe an infrastructure for browsing and multimedia blogging of Web-based information anchored with physical places in an urban environment. The infrastructure is generic in the sense that it may use any means such as GPS, RFID or 2D-barcodes as ubiquitous links anchors to anchor Web-based information, blogs, and services in the physical environment. The infrastructure is inspired from earlier work on open hypermedia, in the sense that the anchoring and blogging functionality can be integrated to augment arbitrary Web sites providing information that is relevant to places or objects in the physical world. The blog and anchor functionality is implemented as a set of Web services running on a server external to the content server. Experiences and design issues from three cases are discussed, which use Semacode-based physical anchoring to support lightweight urban Web applications.
Gaffney, Conor, Dagger, Declan and Wade, Vincent (2008): A survey of soft skill simulation authoring tools. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 181-186. Available online
Soft skill simulations are a convenient and efficient means of delivering engaging educational experiences . Typically these simulations combine hypertext and media files to create a realistic model of real world social situations. However the key impediment to online simulations being adopted as a mainstream approach to teaching soft skills is the complexity involved in their authoring. This paper presents a state of the art survey of existing authoring tools used to compose online soft skill simulations.
Bolchini, Davide, Garzotto, Franca and Paolini, Paolo (2008): Investigating success factors for hypermedia development tools. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 187-192. Available online
What are the key factors that contribute to the "success" of a hypermedia development tool? We have investigated this issue in the context of non ICT professional environments (e.g., schools or small museums), which have limited "in-house" technical competences and must cope with very limited budget. We discuss a set of success factors relevant to hypermedia tools targeted to this audience, and present a tool for multichannel hypermedia development that we have developed with these factors in mind. We report the key results from a wide on-the-field study in which the different success factors have been measured.
Bateman, Scott, Gutwin, Carl and Nacenta, Miguel A. (2008): Seeing things in the clouds: the effect of visual features on tag cloud selections. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 193-202. Available online
Tag clouds are a popular method for visualizing and linking socially-organized information on websites. Tag clouds represent variables of interest (such as popularity) in the visual appearance of the keywords themselves -- using text properties such as font size, weight, or colour. Although tag clouds are becoming common, there is still little information about which visual features of tags draw the attention of viewers. As tag clouds attempt to represent a wider range of variables with a wider range of visual properties, it becomes difficult to predict what will appear visually important to a viewer. To investigate this issue, we carried out an exploratory study that asked users to select tags from clouds that manipulated nine visual properties. Our results show that font size and font weight have stronger effects than intensity, number of characters, or tag area; but when several visual properties are manipulated at once, there is no one property that stands out above the others. This study adds to the understanding of how visual properties of text capture the attention of users, indicates general guidelines for designers of tag clouds, and provides a study paradigm and starting points for future studies. In addition, our findings may be applied more generally to the visual presentation of textual hyperlinks as a way to provide more information to web navigators.
Farzan, Rosta and Brusilovsky, Peter (2008): Where did the researchers go?: supporting social navigation at a large academic. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 203-212. Available online
Dealing with the information overload is an important challenge. Over the last decade researchers have tried to tackle that problem using social technologies. We present a social information access system that helps researchers attending a large academic conference to plan talks they wish to attend. More specifically, we have tried to address the problem of collecting reliable feedback from the community of users. Following "do it for yourself" approach, the system encourages users to add interesting talks to their individual schedules and uses scheduling information for social navigation support. We also report results of evaluation of the system at the ELearn 2007 conference.
Ankolekar, Anupriya and Vrandecic, Denny (2008): Kalpana -- enabling client-side web personalization. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 21-26. Available online
A growing number of websites are recognizing the value of personalization based on a user's context and social network. As more websites become personalized, the resulting experience for users can be rather fragmented. We aim to facilitate a seamless Web personalization experience across websites by enabling personalization to take place at the client and thus allowing personal information about people to reside locally with people. If websites are to script a personalization experience that draws on information held by the user, it is imperative that this information be easily comprehensible by heterogeneous websites. In this paper, we demonstrate how Semantic Web technologies can be used to realize a vision of client-side Web personalization. The contribution of this paper is an architecture that demonstrates the feasibility of our approach and a prototype implementation that establishes its viability.
The visualization of results is a critical component in search engines, and the standard ranked list interface has been a consistently predominant model. The emergence of social media provides a new opportunity to investigate visualization techniques that expose socially derived links between objects to support their exploration. Here we introduce and evaluate network-based visualizations for facilitating the exploration of a Web knowledge space. We developed a force directed network interface to visualize the result sets provided by GiveALink.org, a social bookmarking site. The classifications and tags by users are aggregated to build a social similarity network between bookmarked resources. We administered a user study to evaluate the potential of leveraging such social links in an exploratory search task. During exploration, the similarity links are used to arrange the resources in a semantic layout. Users in our study prefer a hybrid interface combining a conventional ranked list and a two dimensional network map, allowing them to find the same amount of relevant information using fewer queries. This behavior is a direct result of the additional structural information present in the network visualization, which aids them in the exploration of the information space.
Bravo, Javier, Vialardi, Cesar and Ortigosa, Alvaro (2008): Asquare: a powerful evaluation tool for adaptive hypermedia course system. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 219-220. Available online
Currently many methods and tools are being developed to support e-Learning courses. On the one hand, they are used to help students. On the other, a few applications are being developed to help course designers and instructors. In addition, the development of this applications is important for improving the performance of the course. Thus, we proposed in this paper to use data mining methods to aid in the designing of adaptive courses and the evaluation of their effectiveness. Lastly, the results of the implementation of our tool and examples of the utility of Data Mining for teachers is given.
Cena, Federica, Carmagnola, Francesca, Cortassa, Omar, Gena, Cristina, Wang, Yiwen, Stash, Natalia and Aroyo, Lora (2008): Tag interoperability in cultural web-based applications. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 221-222. Available online
This paper presents an approach that shows how user interaction data (tags) generated by one application can be exploited by another one in similar domain for integrating user models in distributed and interactive environments. In particular we discuss the tags interoperability among two adaptive systems into the cultural heritage domain.
Diniz, Madson G. (2008): EFL and hypertext: using webquests to maximize English teaching. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 223-224. Available online
WebQuests have been used as a potential tool in the Educational field. As a technological integrated strategy, students are challenged to think critically and use colloborative learning as a powerful instrument to discover/create knowledge. How can webquests enhance English as a Foreign Language (EFL) students' learning and motivation? WebQuest principles and guidelines will be presented.
Heo, Misook and Yi, Myongho (2008): An empirical study of the learning effect of an ontology-driven information system. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 225-226. Available online
This paper investigates the effect of an ontology-driven information system on users' learning the content of the domain covered by the system. While there have been quite a number of research studies on ontology systems' design, development and evaluation, its impact on users has not been a popular research topic. An experimental system has been developed and constructed with pluralistic, non-linear representations of metadata and relationships. While the expected learning effect did not occur among differently trained participant groups, previous online search experience showed a positive correlation with the performance of the participants.
Hogg, Tad and Szabo, Gabor (2008): Diversity of online community activities. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 227-228. Available online
Web sites where users create and rate content as well as form links display many long-tailed distributions. Using one such site, Essembly, we propose causal mechanisms to explain these behaviors. Unlike purely descriptive models, our mechanisms use only information available to each user. We find the long-tails arise from large diversity of user activity and qualities of the rated content. The models not only explain overall behavior but also allow estimating the qualities of users and content from their early history on the site.
Hsiao, I-Han, Li, Qi and Lin, Yi-Ling (2008): Educational social linking in example authoring. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 229-230. Available online
Each educational resource management website relies on an authoring tool to provide example content. It takes time and experience for authors to create valuable content. Providing support during authoring can affect the quality and quantity of the examples. In this paper we propose a mashup solution to automatically link community wisdom to authors and ease various difficulties in authoring.
Ketterl, Markus, Emden, Johannes and Brunstein, Jörg (2008): Social selected learning content out of web lectures. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 231-232. Available online
Virtpresenter is a system for recording lectures and for re-using recorded contents in other didactic scenarios. Here we demonstrate how the interaction of earlier visitors in form of footprints can be used for extracting relevant passages in time based media. We illustrate how to extract online web lecture snippets for enriching static contents of a course wiki page or student blogs.
Kim, Jae-Kyung, Farzan, Rosta and Brusilovsky, Peter (2008): Spatial annotation and social navigation support for electronic books. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 233-234. Available online
Modern efforts on digitizing electronic books focus on preserving authentic "spatial" representation of the original sources. The new format requires new tools to help users to access, process, and make sense of digital information. This paper presents an approach which assists users of these new "spatial" sources by giving them a combination of annotation and social navigation support. This approach is currently fully implemented and under evaluation in a classroom study.
Panisson, André, Ruffo, Giancarlo and Schifanella, Rossano (2008): X-hinter: a framework for implementing social oriented recommender systems. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 235-236. Available online
Accordingly to the nature of data-driven applications that produce information overload, users need a support to make choices, even without sufficient personal experience of the alternatives. In this context, social networking techniques could be useful applied for finding affinities between users and filter information in a personalized way. After proposing a generalized model for social recommender systems, called X-Hinter, we describe a Java API that provides a set of libraries and tools to build social filtering systems in a wide range of domains. A prototype implementation, named DeHinter, shows the feasibility of the proposed approach in a P2P file sharing application.
Papagelis, Athanasios, Papagelis, Manos and Zaroliagis, Christos (2008): Iclone: towards online social navigation. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 237-238. Available online
For a place that gathers millions of people the Web seems pretty lonely at times. This is mainly due to the current predominant browsing scenario; that of an individual participating in an autonomous surfing session. We believe that people should be seen as an integral part of the browsing and searching activity towards a concept known as social navigation. Based on this observation we present iClone (www.iclone.com), a social web browser that is able to raise awareness of other people surfing similar websites at the same time by utilizing temporal correlations of their web history logs and to facilitate online communication and collaboration.
Pilgrim, Chris J. (2008): Improving the usability of Web 2.0 applications. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 239-240. Available online
Web 2.0 is revolutionizing the way that users access content and interact with each other on the Web. Unfortunately, many developers are inspired by what is technologically possible possibly disregarding good design practice and fundamental theory. Very little research on Web 2.0 usability is reported in the literature. This paper reports progress on an investigation into the usability of Web 2.0 applications through an empirical study of the level of disorientation and cognitive overhead that users might experience. The outcomes of this project aim to provide an empirical basis for the development of design guidelines to improve Web 2.0 usability.
Pourabdollah, Amir, Ashman, Helen and Brailsford, Tim (2008): Are we talking about the same structure?: a unified approach to hypertext links, xml, rdf and zigzag. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 241-242. Available online
There are many different hypertext systems and paradigms, each with their apparent advantages. However the distinctions are perhaps not as significant as they seem. If we can reduce the core linking functionality to some common structure, which allows us to consider hypertext systems within a common model, we could identify what, if anything, distinguishes hypertext systems from each other. This paper offers such a common structure, showing the conceptual similarities between each of these systems and paradigms.
Rubart, Jessica (2008): Hypermedia design patterns. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 243-244. Available online
This poster aims at motivating the hypermedia community to identify and describe hypermedia patterns focusing on software design. Design patterns support a shared vocabulary and a shared understanding about design models. In addition, they facilitate reusing prior experience for new designs. An example hypermedia design pattern is provided.
Tomsa, Marek and Bielikova, Maria (2008): Hyperlinks visualization using social bookmarking. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 245-246. Available online
We present a method for navigation support by visualization of actual web page context. We browse and incrementally visualize a graph representing an abstraction of web navigation where nodes represent web pages and edges represent relationships between them expressed either by explicit links (one page linking to another through the content) or implied relationships (relevant pages several clicks away). We proposed several metrics for edge relevance evaluation. In the metrics, existing metadata in form of tags associated with bookmarks offered by collaborative social bookmarking sites is employed and user preferences represented by their tag usage are taken into account.
In this paper we address the problem of browser extensibility, needed to support the evolving nature of the web. Standards for supporting multimedia content by browsers are constantly updated, extended and introduced while the browser support is left behind. We present a novel approach to add browser support for content adhering to a new standard. Only a small set of requirements needs to be implemented as part of the browser's software, the rest is accounted by client-side code. Client-side code has the advantage that it can account for missing functionality with no changes to the browser, thus making it more dynamic, easier to implement, and enabling third-party developers to contribute. At the same time, it is risk-free for users accessing other content types. On the downside, client-side code suffers from degraded performance and potentially introduces security concerns.
Vuillemot, Romain and Rumpler, Béatrice (2008): Mapping visualization on-demand onto a virtual globe: an appealing complement to browser-based navigation. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 249-250. Available online
Current browser-based navigation is a universal and powerful tool, but lacks of three useful features: overview of the global website structure, efficient history browsing and an alternative to link-link navigation. By combining Visualization on-demand (Vizod) with an interactive virtual globe, we tackled these issues by means of multi-resolutions maps displayed according to user's interactions and preferences. We provided in this way a contextual hypertext navigation, each page being assigned locations and links on top of a virtual map. We built up and performed experiments of a prototype providing a smooth, appealing and promising complement to browser-based navigation.
Wang, Weigang (2008): Powermeeting: gwt-based synchronous groupware. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 251-252. Available online
The Web has been widely used as a platform for asynchronous collaboration. However, Web based synchronous groupware are still rare, especially those using standard Web browser as front-end. In this demonstration, a groupware system built on GWT and AJAX Push technology will be presented. The system provides a common foundation for developing synchronous groupware applications that consist of a set of groupware tools for various specific collaborative activities. It provides not only a desktop-application like user experience within a browser, but also retains the common Web user experience with link following and backward/forward navigation. The objective of this work is to make synchronous collaboration an integral part of collaboration support on the Web.
Yalcin, Senom T. (2008): Writing on the blog: an assemblage analysis. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 253-254. Available online
By examining two academic blogs over a period of 3 months, this study aims to understand blog writing by defining writing as constructing dynamic trajectories and a function of its environment. An analysis for identifying the constructed trajectories, which provide information on the location and nature of the connections, as well as the content; yield both information on the parts (the blog) that construct the network, and the network as a whole (the blog+its environment).
Yudelson, Michael and Goreva, Natalya (2008): Providing social navigation within annotated examples. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 255-256. Available online
Social navigation is a promising way to guide users in hypermedia environments. In this paper we present Social WebEx, a system that provides social navigation to line-by-line annotated code examples. Social WebEx is a version of "plain" WebEx that only provides access to annotations of lines of code. In social WebEx users are able to see their own code browsing traffic of examples as well as the traffic of their peers. The social version of the system has been used for over a year as an optional learning tool in both graduate and undergraduate programming coursers in a number of schools.
Petersen, Rasmus Rosenqyist and Wiil, Uffe Kock (2008): ASAP: a planning tool for agile software development. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 27-32. Available online
This paper describes the ASAP planning tool. ASAP uses different hypertext structuring mechanisms to provide support for project planning. The design concepts and prototype features are inspired from previous work on structural computing and spatial hypertext. A use scenario demonstrates the capabilities of the tool to support the Blitz Planning activity from the Crystal Clear agile software development methodology. Future work is aimed at broadening the applicability of ASAP towards general project planning.
Kleinberg, Jon M. (2008): Link structures, information flow, and social processes. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 3-4. Available online
In the ongoing movement toward socially-produced information resources, we are increasingly able to look through the content being created and see the individuals, incentives, and larger social processes at work. Designing and working with large-scale participatory social computing applications requires that we think not just about technological issues, but also about fundamental principles of human social interaction. Through the digital traces that these applications generate, we can begin to quantify and reason about such principles at unprecedented levels of scale and resolution. In this talk, we consider a crucial type of social process in this setting -- the mechanisms by which information flows through groups of people engaged in sharing and synthesizing knowledge. As information, ideas, opinions, and beliefs spread through an underlying social network, their dynamics resemble that of an epidemic, moving "contagiously" from person to person. But social contagion is different from biological contagion in many respects; understanding the analogies and contrasts between these two kinds of processes leads us to consider the rich temporal characteristics of information flow within a network and the complex decision rules by which people choose to act on new information. The result is a richer picture of the communities that create knowledge and its interlinkages, and of the resources that ultimately arise from these processes.
Szomszor, Martin N., Cantador, Iván and Alani, Harith (2008): Correlating user profiles from multiple folksonomies. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 33-42. Available online
As the popularity of the web increases, particularly the use of social networking sites and style sharing platforms, users are becoming increasingly connected, sharing more and more information, resources, and opinions. This vast array of information presents unique opportunities to harvest knowledge about user activities and interests through the exploitation of large-scale, complex systems. Communal tagging sites, and their respective folksonomies, are one example of such a complex system, providing huge amounts of information about users, spanning multiple domains of interest. However, the current Web infrastructure provides no mechanism for users to consolidate and exploit this information since it is spread over many desperate and unconnected resources. In this paper we compare user tag-clouds from multiple folksonomies to: (a) show how they tend to overlap, regardless of the focus of the folksonomy (b) demonstrate how this comparison helps finding and aligning the user's separate identities, and (c) show that cross-linking distributed user tag-clouds enriches users profiles. During this process, we find that significant user interests are often reflected in multiple Web 2.0 profiles, even though they may operate over different domains. However, due to the free-form nature of tagging, some correlations are lost, a problem we address through the implementation and evaluation of a user tag filtering architecture.
Golder, Scott (2008): Measuring social networks with digital photograph collections. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 43-48. Available online
The ease and lack of cost associated with taking digital photographs have allowed people to amass large personal photograph collections. These collections contain valuable information about their owners' social relationships. This paper is a preliminary investigation into how digital photo collections can provide useful data for the study of social networks. Results from an analysis of 23 subjects' photo collections demonstrate the feasibility of this approach. The relationship between perceived closeness and network position, as well as future questions, are also discussed.
Choudhury, Munmun De, Sundaram, Hari, John, Ajita and Seligmann, Doree Duncan (2008): Dynamic prediction of communication flow using social context. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 49-54. Available online
In this paper, we develop a temporally evolving representation framework for context that can efficiently predict communication flow in social networks between a given pair of individuals. The problem is important because it facilitates determining social and market trends as well as efficient information paths among people. We describe communication flow by two parameters: the intent to communicate and communication delay. To estimate these parameters, we design features to characterize communication and social context. Communication context refers to the attributes of current communication. Social context refers to the patterns of participation in communication (information roles) and the degree of overlap of friends between two people (strength of ties). A subset of optimal features of the communication and social context is chosen at a given time instant using five different feature selection strategies. The features are thereafter used in a Support Vector Regression framework to predict the intent to communicate and the delay between a pair of individuals. We have excellent results on a real world dataset from the most popular social networking site, www.myspace.com. We observe interestingly that while context can reasonably predict intent, delay seems to be more dependent on the personal contextual changes and other latent factors characterizing communication, e.g. 'age' of information transmitted and presence of cliques among people.
Jatowt, Adam, Kawai, Yukiko, Ohshima, Hiroaki and Tanaka, Katsumi (2008): What can history tell us?: towards different models of interaction with document histories. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 5-14. Available online
The current Web is a dynamic collection where little effort is made to version pages or to enable users to access historical data. As a consequence, they generally do not have sufficient temporal support when browsing the Web. However, we think that there are many benefits to be obtained from integrating documents with their histories. For example, a document's history can enable us to travel back through time to establish its trustworthiness. This paper discusses the possible types of interactions that users could have with document histories and it presents several examples of systems that we have implemented for utilizing this historical data. To support our view, we present the results of an online survey conducted with the objective of investigating user needs for temporal support on the Web. Although the results indicated quite low use of Web archives by users, they simultaneously emphasized their considerable interest in page histories.
Choudhury, Munmun De, Sundaram, Hari, John, Ajita and Seligmann, Doree Duncan (2008): Can blog communication dynamics be correlated with stock market activity?. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 55-60. Available online
In this paper, we develop a simple model to study and analyze communication dynamics in the blogosphere and use these dynamics to determine interesting correlations with stock market movement. This work can drive targeted advertising on the web as well as facilitate understanding community evolution in the blogosphere. We describe the communication dynamics by several simple contextual properties of communication, e.g. the number of posts, the number of comments, the length and response time of comments, strength of comments and the different information roles that can be acquired by people (early responders / late trailers, loyals / outliers). We study a "technology-savvy" community called Engadget (http://www.engadget.com). There are two key contributions in this paper: (a) we identify information roles and the contextual properties for four technology companies, and (b) we model them as a regression problem in a Support Vector Machine framework and train the model with stock movements of the companies. It is interestingly observed that the communication activity on the blogosphere has considerable correlations with stock market movement. These correlation measures are further cross-validated against two baseline methods. Our results are promising yielding about 78% accuracy in predicting the magnitude of movement and 87% for the direction of movement.
Shi, Xiaolin, Bonner, Matthew, Adamic, Lada A. and Gilbert, Anna C. (2008): The very small world of the well-connected. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 61-70. Available online
Online networks occupy an increasingly larger position in how we acquire information, how we communicate with one another, and how we disseminate information. Frequently, small sets of vertices dominate various graph and statistical properties of these networks and, because of this, they are relevant for structural analysis and efficient algorithms and engineering. For the web overall, and specifically for social linking in blogs and instant messaging, we provide a principled, rigorous study of the properties, the construction, and the utilization of subsets of special vertices in large online networks. We show that graph synopses defined by the importance of vertices provide small, relatively accurate portraits, independent of the importance measure, of the larger underlying graphs and of the important vertices. Furthermore, they can be computed relatively efficiently.
Dellschaft, Klaas and Staab, Steffen (2008): An epistemic dynamic model for tagging systems. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 71-80. Available online
In recent literature, several models were proposed for reproducing and understanding the tagging behavior of users. They all assume that the tagging behavior is influenced by the previous tag assignments of other users. But they are only partially successful in reproducing characteristic properties found in tag streams. We argue that this inadequacy of existing models results from their inability to include user's background knowledge into their model of tagging behavior. This paper presents a generative tagging model that integrates both components, the background knowledge and the influence of previous tag assignments. Our model successfully reproduces characteristic properties of tag streams. It even explains effects of the user interface on the tag stream.
Chi, Ed H. and Mytkowicz, Todd (2008): Understanding the efficiency of social tagging systems using information theory. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 81-88. Available online
Given the rise in popularity of social tagging systems, it seems only natural to ask how efficient is the organically evolved tagging vocabulary in describing underlying document objects? Does this distributed process really provide a way to circumnavigate the traditional "vocabulary problem" with ontology? We analyze a social tagging site, namely del.icio.us, with information theory in order to evaluate the efficiency of this social tagging site for encoding navigation paths to information sources. We show that information theory provides a natural and interesting way to understand this efficiency -- or the descriptive, encoding power of tags. Our results indicate the efficiency of tags appears to be waning. We discuss the implications of our findings and provide insight into how our methods can be used to design more usable social tagging software.
Kolb, David A. (2008): The revenge of the page. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 89-96. Available online
Writers of literary hypertext have urged complexly linked hypertext forms. Some writers have applied this to expository and argumentative hypertext, taking advantage of hypertext's ability to expand the "margins" of a document in new directions. Where argumentative issues or contexts are complex and self-reflexive enough, these writers urge that hypertexts become complex multi-dimensional expository and argumentative texts with elaborate rhetorical and argumentative structures that take place over sequences of links. However this ideal is challenged by developments on the Web, where argumentative hypertexts are dominated by a linked mini-essay style that uses one-step link patterns for its rhetorical moves. Was the ideal of complex hypertext rhetorical structures mistaken? This essay analyzes the situation, argues for the viability of more complex hypertexts, suggests some causes for the dominance of the single page and single-step rhetorical move, and looks at some developments that may challenge this dominance.
Recuero, Raquel da Cunha (2008): Information flows and social capital in weblogs: a case study in the Brazilian blogosphere. In: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia 2008. pp. 97-106. Available online
Blogs are tools for publishing information that have become very popular due to the way they facilitate the process of publishing on the Internet. Due to their popularity, blogs influence how information flows in cyberspace. This paper deals with the relations between bloggers' perceived social capital and motivations with the information they choose to publish. Based on a case study of a network of 48 weblogs, 32 interviews and 988 analyzed memes, we show how, for the studied case, information flow is influenced by bloggers' motivations and perceptions.