Although information visualization (infovis) technologies have proven indispensable tools for making sense of complex data, wide-spread deployment has yet to take hold, as successful infovis applications are often difficult to author and require domain-specific customization. To address these issues, we have created prefuse, a software framework for creating dynamic visualizations of both structured and unstructured data. prefuse provides theoretically-motivated abstractions for the design of a wide range of visualization applications, enabling programmers to string together desired components quickly to create and customize working visualizations. To evaluate prefuse we have built both existing and novel visualizations testing the toolkit's flexibility and performance, and have run usability studies and usage surveys finding that programmers find the toolkit usable and effective.

Never before in history has data been generated at such high volumes as it is today. Exploring and analyzing the vast volumes of data has become increasingly difficult. Information visualization and visual data mining can help to deal with the flood of information. The advantage of visual data exploration is that the user is directly involved in the data mining process. There are a large number of information visualization techniques that have been developed over the last two decades to support the exploration of large data sets. In this star report, we provide an overview of information visualization and visual data mining techniques, and illustrate them using a few examples.

Abstract — Information visualisation is about gaining insight into data through a visual representation. This data is often multivariate and increasingly, the datasets are very large. To help us explore all this data, numerous visualisation applications, both commercial and research prototypes, have been designed using a variety of techniques and algorithms. Whether they are dedicated to geo-spatial data or skewed hierarchical data, most of the visualisations need to adopt strategies for dealing with overcrowded displays, brought about by too much data to fit in too small a display space. This paper analyses a large number of these clutter reduction methods, classifying them both in terms of how they deal with clutter reduction and more importantly, in terms of the benefits and losses. The aim of the resulting taxonomy is to act as a guide to match techniques to problems where different criteria may have different importance, and more importantly as a means to critique and hence develop existing and new techniques.

Although constructed for researchers to share news and information, Usenet quickly developed into a social environment with varied styles of interactions. Unfortunately, the browsers developed to view the shared messages fail to effectively convey the rich social features of a newsgroup, let alone all of Usenet. The goal of our research is to use the salient features of social interaction to build a “legible ” interactive visual representation of Usenet. In this paper, we introduce our approach to developing this type of visualization, discussing our theoretical framework, questions considered to access the socially salient features, and a series of design iterations used for exploring how to develop a visual language that conveys social meaning. Although this paper represents a work in progress, we hope that this approach and our initial iterations help build a framework for future directions.

The field of information visualization offers little methodological guidance to practitioners who seek to design novel systems. Though many sources describe the foundations of the domain, few discuss practical methods for solving visualization problems. One frequently cited guideline to design is the “Visual Information-Seeking Mantra”, proposed by Shneiderman in 1996. Although often used to inform the design of information visualization systems, it is unclear what use this has been for visualization designers. We reviewed the current literature that references the Mantra, noting what authors have found useful about it and why they cite it. The results indicate a need for empirical validation of the Mantra and for a method, such as design patterns, to inform a holistic approach to visualisation design.

This report is broken down into four main sections, firstly giving the primary aims of the proposed research, followed by a review of background reading of present Information Visualisation (IV) techniques, which are categorised using an existing framework. This is followed by a description of the general visualisation problem we are concerned with plus a description of the specific area where such a visualisation could be of benefit. We then discuss the visualisation techniques that address situations that have the greatest similarity to our own problem, and explain why they still lack suitability for our purposes. Then, two prototypes that are under development are described, and the report finishes with a breakdown of proposed future work

Compared with stationary environments, mobile devices suffer from a number of limitations like small screen space, limited processing power and bandwidth. Thus, it is very difficult and expensive to browse large images by using current mobile hardware. In this publication a new image browsing technique especially designed for mobile devices with limited screen space is introduced, and a completely new concept to communicate important image properties based on a well-defined grid structure is proposed. As every browsing technique needs reasonable concepts for user interaction, this publication introduces intuitive ways for image exploration, which need only little action of the user during browsing and processing power to calculate an appropriate image representation. To decrease the need for expensive bandwidth in remote environments, it will also be shown how to combine this browsing technique with image compression and transmission. Thus, a whole system for image communication is presented. Due to its excellent compression performance and flexibility, the modern JPEG2000 image coding standard is adopted as a foundation of the proposed system regarding a compliant compression and efficient transmission of the image. Concrete performance measures show the applicability of the introduced system.

Visualization can be viewed as a process that transforms raw data (value) into views. There has been two major category of data process models that have been proposed to model the visualization transformation process. This paper seeks to compare the Data Flow Models and the Data State Models. Specifically, it proves that, in terms of expressiveness, anything that can represented using the Data Flow Model can also be represented using the Data State Model, and vice versa.

Abstract—Even though information visualization (InfoVis) research has matured in recent years, it is generally acknowledged that the field still lacks supporting, encompassing theories. In this paper, we argue that the distributed cognition framework can be used to substantiate the theoretical foundation of InfoVis. We highlight fundamental assumptions and theoretical constructs of the distributed cognition approach, based on the cognitive science literature and a real life scenario. We then discuss how the distributed cognition framework can have an impact on the research directions and methodologies we take as InfoVis researchers. Our contributions are as follows. First, we highlight the view that cognition is more an emergent property of interaction than a property of the human mind. Second, we argue that a reductionist approach to study the abstract properties of isolated human minds may not be useful in informing InfoVis design. Finally we propose to make cognition an explicit research agenda, and discuss the implications on how we perform evaluation and theory building. Index Terms—Information visualization, distributed cognition, interaction, representation, theory and methods 1

Classifications of visualization are often based on technical criteria, and leave out artistic ways of visualizing information. Understanding the differences between information visualization and other forms of visual communication provides important insights into the way the field works, though, and also shows the path to new approaches. We propose a classification of several types of information visualization based on aesthetic criteria. The notions of artistic and pragmatic visualization are introduced, and their properties discussed. Finally, the idea of visualization criticism is proposed, and its rules are laid out. Visualization criticism bridges the gap between design, art, and technical/pragmatic information visualization. It guides the view away from implementation details and single mouse clicks to the meaning of a visualization. 1