Abstract: Visualization technology can be used to graphically illustrate various concepts in computer science. We argue that such technology, no matter how well it is designed, is of little educational value unless it engages learners in an active learning activity. Drawing on a review of experimental studies of visualization effectiveness, we motivate this position against the backdrop of current attitudes and best practices with respect to visualization use. We suggest a new taxonomy of learner engagement with visualization technology. Grounded in Bloom's well-recognized taxonomy of understanding, we suggest metrics for assessing the learning outcomes to which such engagement may lead. Based on these taxonomies of engagement and effectiveness metrics, we present a framework for experimental studies of visualization effectiveness. Interested computer science educators are invited to collaborate with us by carrying out studies within this framework.

Abstract: We present an architecture that enables information visualization activities within a database environment Our approach presents an abstraction of this transformation process, which we call mapping The implementation of the mapping process is controlled by the end-user through a Map, which can be used to add order and scale to data

Abstract: The exploration of heterogenous information spaces requires suitable mining methods as well as effective visual interfaces. Most of the existing systems concentrate either on mining algorithms or on visualization techniques. This paper describes a flexible framework for visual data mining which combines analytical and visual methods to achieve a better understanding of the information space. We provide several pre-processing methods for unstructured information spaces, such as a flexible hierarchy generation with user-controlled refinement. Moreover, we develop new visualization techniques, including an intuitive focus+context technique to visualize complex hierarchical graphs. A special feature of our system is a new paradigm for visualizing information structures within their frame of reference.

Abstract: We present the usage of a non-discrete degree of interest (DOI) function, obtained by brushing multi-valued 3D simulation data in information visualization views, to define opacity, color, and geometrical transfer functions for 3D rendering in a scientific visualization view via linking. To reflect the smooth nature of features in flow simulation data, smooth brushing was chosen. Different available views and interaction methods of a prototype system are discussed, and examples from 3D flow simulation are shown.

Abstract: We describe a new information structure composed of multiple intersecting hierarchies, which we call Polyarchies. Visualizing polyarchies enables use of novel views for discovery of relationships which are very difficult using existing hierarchy visualization tools. This paper will describe the visualization design and system architecture challenges as well as our current solutions. A Mid-Tier Cache architecture is used as a "polyarchy server" which supports a novel web-based polyarchy visualization technique, called Visual Pivot. A series of five user studies guided iterative design of Visual Pivot

Abstract: An important step in the design of visual languages is the specification of the graphical objects and the composition rules for constructing feasible visual sentences. The presence of different typologies of visual languages, each with specific graphical and structural characteristics, yields the need to have models and tools that unify the design steps for different types of visual languages. To this aim, in this paper we present a formal framework of visual language classes. Each class characterizes a family of visual languages based upon the nature of their graphical objects and composition rules. The framework has been embedded in the Visual Language Compiler–Compiler (VLCC), a graphical system for the automatic generation of visual programming environments.

Abstract: The SHriMP (Simple Hierarchical Multi-Perspective) visualization technique was designed to enhance how people browse and explore complex information spaces. SHriMP uses a nested graph view to present information that is hierarchically structured. It introduces the concept of nested interchangeable views to allow a user to explore multiple perspectives of information at different levels of abstraction. SHriMP combines a hypertext following metaphor with animated panning and zooming motions over the nested graph to provide continuous orientation and contextual cues for the user. In this demo, we show how these ideas are proving useful in the areas of software visualization, knowledge management and flow diagram visualization.

Abstract: This paper presents a perceptually motivated formal framework for effective visualization of relational data. In this framework, the intended structure of data and the perceptual structure of visualizations are formally and uniformly defined in terms of relations that are induced on data and visual elements by data and visual attributes, respectively. Visual attributes are analyzed and classified from the perceptual point of view and in terms of perceptual relations that they induce on visual elements. The presented framework satisfies a necessary condition for effective data visualizations. This condition is formulated in terms of a structure preserving map between the intended structure of data and the perceptual structure of visualization.

Abstract: ing. The individual page or screen is a microcosm of the complete book, site product. The result is a complete codified system of graphic standards, effective for both the reader and the producer. Abstracting creates a system of standards that simplify text organization, create consistent approaches to preprocessing information, and establish a unique customized look for an organization's products. See Fig. 13.14. Other Page Design Techniques White Space. White space (or empty space) is one of the most underutilized tools of design, yet is extremely effective. It can be used to visually open up a page, focus attention, help group like kinds of information, as well as provide a rest for the reader's eye and create the perception of simplicity and ease of use. The Grid. A grid is a system for distribution of visual elements in a clearly intelligible order. Grids, as part of a design system, determine the horizontal placement of columns, and the vertical placement of headlines, text, graphics, and images. This visual organization or grid system is a series of consistent relationships, alignments, and spatial organization. The grid acts as a blueprint of the page that can be used again and again to create additional pages that appear related, but have different information. When the grid system is understood, it forms the basis for consistent application and extension of the design by others who also understand the intention of the system. Every good design has an underlying structure or grid, as a basis to create a consistent look and feel to a program, web site, book, or sets of any of these. One could think of the grid as the visual analogy of the metal beams as a framework of a high-rise buildings. Each floor has the same underlying elements. Such as windows, elevators, plumbing, but depending on the use of each floor, will be built and look very different. The grid is also a tool to improve usability. For example, if a user can anticipate a button to always appear in the same place, or help always available in the same way, this greatly improves the usefulness of the product or program and ultimately its success. Placement all visual elements such as buttons and help are specified on the grid. Field of Vision. Field of vision refers to what a user can see on a page with little or no eye movement; it is the main area where the eye rests to view most of the page. A good design places key elements in the primary field of vision. It should reflect and reinforce the information hierarchy. Size, contrast, grouping, relationships, and movement are tools that create and reinforce field of vision. The user will see first what is visually strongest, not necessarily what is largest or at the top of a page. This is particularly important for online information, because of limitations of page real estate and dense information environment. One can easily experience these concepts, as well as the strength of peripheral vision, when looking at a page that has a banner advertisement or moving graphics. It is virtually impossible to ignore or focus attention on the primary field of vision when there is winking and blinking somewhere else on the page. Superfluous use of visual devices in fact reduces the value of the information by distracting and disturbing the user's desire and ability to focus, read, and understand. Proximity. This concept applies to the placement of visual elements physically close, so they will be understood as related elements. For example, if there were 3 images with captions on a page, it would be more useful to place each caption near the image if explains, though it might be more efficient to place the three captions together in one block of type on the page. The Illusion of Depth. Though the online world exists on a two-dimensional space, various visual techniques can be used to create the illusion of depth, much like the painters of the Italian Renaissance period. Visual cues, such as layering, overlapping, perspective, size, contrast, and color can reinforce visual hierarchy by giving the illusion that one element appears on top of or in front of another. Charts, Diagrams, Graphics, and Icons The goal of any visual device is to provide the fastest, most efficient path to understanding ideas, as well as to make it clearer and more compelling. Useful, effective graphics can act much like visual shorthand, particularly important when the real estate of the page is limited. A good graphic can eliminate the need for text and communicate across cultures. However, a bad graphic that is unclear and must be reinforced by long captions can be worse than none at all. The old cliche, a picture is worth a thousand words, is true only if it is efficient and effective. In stressful situations, people do have the time to read or the ability to focus on lengthy text or complex visuals. Though more difficult to achieve brevity and simplicity in such cases have greater value. People prefer well-designed charts, diagrams, and illustrations that quickly and clearly communicate complex ideas and information such as comparisons or analysis. Studies show that images are retained long after the reader is finished reading. Done correctly, visual images can be used to make the information more memorable and effective. At a minimum, a good illustration or graphic can often improve performance simply because it increases user motivation. Visuals are powerful communications tools. They can be used to:

Abstract: Evaluating user interfaces is usually accomplished to detect design problems in layout and interaction. One possible way to evaluate image quality in computer graphics is visual inspection by experts. Information visualization techniques are usually presented showing their use in experimental situations, employing some kind of analysis. Nevertheless, few works have specifically addressed the evaluation of such techniques. This work reports our results towards the definition of criteria for evaluating information visualization techniques, addressing the evaluation of visual representation and interaction mechanisms as a first step.

Abstract: Relational databases provide significant flexibility to organize, store, and manipulate an infinite variety of complex data collections. This flexibility is enabled by the concept of relational data schemas, which allow data owners to easily design custom databases according to their unique needs. However, user interfaces and information visualizations for accessing and utilizing databases have not kept pace with this level of flexibility. Visualizations need to integrate multiple tables and diverse visualization tools into custom solutions. This paper describes advances to Snap-Together Visualization, introduces Visualization Schemas, and presents an extensible system architecture. The Snap model for custom multiple-view visualization establishes an analogy to the relational data model, enabling coordinated data design and visualization design. Visualization Schemas are a natural extension to data schemas, and provide a user interface that enables data owners to rapidly construct and disseminate custom visualizations without programming. The web-based software architecture supports run-time extensibility, enabling end-user integration and dissemination of diverse data and visualization tools from the field.

Abstract: The authors describe a new information structure composed of multiple intersecting hierarchies, which we call a Polyarchy. Visualizing polyarchies enables use of novel views for discovery of relationships which are very difficult using existing hierarchy visualization tools. This paper will describe the visualization design and system architecture challenges as well as our current solutions. Visual Pivot is a novel web-based polyarchy visualization technique, supported by a 'polyarchy server' implemented with a Mid-Tier Cache architecture. A series of five user studies guided iterative design of Visual Pivot. Finally, the effectiveness of animation in Visual Pivot is discussed.

Abstract: Adaptive visualization is a technology that can enhance the power of program visualization. The idea of adaptive visualization is to adapt the level of details in a visualization to the level of student knowledge about these constructs. This paper presents an adaptive visualization system, WADEIn, that was developed to explore visualization of expression execution during program execution - a under-explored area in visualization research. WADEIn has been designed as a component of our distributed Web-based adaptive educational system KnowledgeTree, however it also can be used as a standalone educational tool. The system has been pilot-tested in the context of a real university course with 40 students and is available on the Web for public use.

Abstract: Tracking the growth of scientific knowledge has become increasingly challenging even in one’s own specialized field due to the vast amount of new scientific publications become available. As a rapidly advancing and expanding field of computing and information technology, information visualization has focused on the discovery of interrelationships among various scientific publications. However, visualizing intrinsic structures among documents in scientific literatures can only capture some aspects of scientific knowledge. For example, the number of citations received by a scientific work is a widely accepted hallmark of its significance. This chapter describes approaches to the visualization of knowledge structures with emphasis on the role of citation-based methods. Instead of relying upon occurrence patterns of content-bearing words, visualization of knowledge structures aims to capture perceived intellectual structures of a particular knowledge domain. An ultimate goal for the visualization of knowledge structures is to provide scientists with a tool that can detect the existence of a scientific paradigm and movements of such paradigms. This chapter also includes a summary of the history of tracking the growth of scientific knowledge. The state of the art is presented to highlight the trend of future research.

Abstract: This paper describes performance visualization with its purposes, significance, and our prototype system. Performance visualization provides us with a new user interface for music systems, a non-subjective explanation and judgment for musical expression, and a visual aid to understand, analyze, and compare performances and their musical structures. It will also introduce a more challenging research on designing a musical data mining interface not by tags nor by contents but by the mood. Other challenges include finding qualitative characteristics of music with analysis methods for information visualization and synesthesia between visualized and sonified information. We will describe which information should be shown on the visualized figures for expressive performance. Then we will show our prototype system to visualize expressive performance consisting of several instruments.

Abstract: Relational databases provide significant flexibility to organize, store, and manipulate an infinite variety of complex data collections. This flexibility is enabled by the concept of relational data schemas, which allow data owners to easily design custom databases according to their unique needs. However, user interfaces and information visualizations for accessing and utilizing databases have not kept pace with this level of flexibility. This paper introduces the concept of visualization schemas, based on the Snap-Together Visualization model, which are analogous to relational data schemas. Visualization schemas enable users to rapidly construct customized multiple-view visualizations for databases in a similarly flexible fashion without programming. Since the design of appropriate visualizations for a given database depends on the data schema, visualization schemas are a natural analogy to the data schema concept.

Abstract: Searching for information on the web is hard; the user may not know what they are looking for, they may refine their search from information gathered by preliminary naive searches, and they may be looking for luminous sites that have many external links so that they can browse further. Information visualization can aid the user in many of these search related tasks. Certainly, the user is familiar with browsing and manipulating the search results through textual style interfaces, but they would gain a better understanding of the information through different presentation methods. Thus, we believe rank ordered lists should be used along-side abstract information visualization presentations. We present a system that displays multiple views of search result information. It provides views for displaying abstract visualization designs using multiform glyphs as well as a ranked text based list. Our engine also retrieves detailed information about the located sites (such as size of page, and quantities of internal and external links); and we describe two glyph designs that display this rich information.

Abstract: This paper describes the VITE system, a visual workspace that supports two-way mapping for projecting structured information to a two-dimensional workspace and updating the structured information based on user interactions in the workspace. This is related to information visualization, but reflecting visual edits in the structured data requires a two-way mapping from data to visualization and from visualization to data. VITE provides users with an interface for designing two-way mappings. Mappings are reusable on different datasets and may be switched within a task. An evaluation of VITE was conducted to study how people use two-way mapping and how two-way mapping can help in problem solving tasks. The results show that users could quickly design visual mappings to help their problem-solving tasks. Users developed more sophisticated strategies for visual problem-solving over time.

Abstract: We discuss a fusion-based visualization method to analyze a multivariate climate dataset and its metadata. The primary difference between a conventional visualization and a fusion-based visualization is that the former draws on a single image whereas the latter draws on multiple see-through layers, which are then overlaid on each other to form the final visualization. We propose optimized colormaps to highlight subtle features that would not be shown with conventional colormaps. We present fusion techniques that integrate multiple single-purpose visualization techniques into the same viewing space. Our highly flexible fusion approach allows scientists to explore multiple parameters concurrently by mixing and matching images without frequently reconstructing new visualizations from the data for every possible combination. Although our primary visualization application is climate modeling, we show with examples that our fundamental design - fusing layers of data images for multivariate visualization - can be generalized for other information visualization applications.

Abstract: Almost all vehicles soon will acquire advanced user interfaces with specialized information visualization. This revolution poses significant human factors issues, but also new challenges of appeal, cultural orientation, and branding. This article describes considerations beyond traditional human factors and shows conceptual visual prototypes that explore new approaches to vehicle information displays.

Abstract: Documentation has long played a key role in aiding program understanding. Graphical forms of documentation rely on software visualization techniques to make complicated information easier to understand. However, it is an open question exactly which types of graphical documentation are most suitable for which types of program understanding tasks (and in which specific usage contexts). This paper describes preliminary work towards a task-oriented classification of program visualization techniques. The classification is currently descriptive in nature, and divides the visualization techniques into three classes (static, interactive, and editable) based on the level of end-user interaction with the generated graphical documentation. The primary advantage of a task-oriented classification is that it will ultimately map common activities related to program understanding to specific types of software visualization. A summary of how the descriptive classification was used to structure the selection of software visualization tools to support program understanding in an industrial context is provided.

Abstract: Information visualization, aided by ever more accessible computational resources, continues to grow in popularity and significance. The capability to generate complex imagery by computer is often necessary but not always sufficient to gain the desired insight. The success of a visual representation in a given context may be affected by many variables, not the least of which is the individual user's experience. Even if a precise relationship could be found between context and "best" visual representation, the complete articulation of a context is practically impossible. In other fields, this is known as sensitive dependence to initial conditions. A more feasible alternative is to begin with an incomplete articulation of a context and allow the user to interactively develop and refine it. Although most computer interfaces for information visualization tools are predominantly verbal, a predominantly visual interface can have significant advantages. Such an interface allows users to avoid the usual translations between visual and verbal modes and it removes users' need for a specialized visualization vocabulary. A visual interface can also shift the focus of the visualization process from the data towards the user These ideas are discussed in the context of a prototype tool, the design of which is illustrated with an example, and the evaluation of which has provided many positive results.

Abstract: In exploring large volumes of information, more often than not, one single visualization is not sufficient for grasping the whole data set. This may be due to different reasons: the screen real-estate is limited, the user's capacity for comprehending a large data set also has limits, different views or perspectives of the same data may be needed to grasp all the details, and so on. Multiple visualizations allow the user to explore large amounts of complex information more easily and rapidly We believe that one of the strengths of 3D metaphoric information visualization will emerge from the combined use of several interacting tools, each potentially depicting different views of the information. This paper presents work done on using multiple views for the visualization of abstract information via metaphoric representations.

Abstract: The idea of using visualization technology to enhance the understanding of abstract concepts like data structures and algorithms, has become widely accepted. One of the main obstacles for fully taking advantage of algorithm visualization seems to be the time and effort required to design, integrate and maintain the visualizations. The process of creating software visualizations (SV) is thought to be too laborious to be worthwhile (Hundhausen et al., 2002). Thus, “a future challenge is to create tools and methodologies which will result in the use of SVs by the majority of computer science educators” (Domingue, 2002). Several attempts have been made to introduce a system that levels out the burden of creating new visualizations (Haajanen et al., 1997; Korhonen and Malmi, 2002; LaFollette et al., 2000; Naharro-Berrocal et al., 2002). However, none of these systems has gained wide recognition. Therefore we have surveyed several systems in order to identify why the creation of software visualization is such a laborious process. The users of visualization systems can be divided into two classes. First, there are producers, who use the systems to create visualizations. Second, there are consumers who benefit from the visualizations. By using, for example, Jeliot (Haajanen et al., 1997), it is possible for the consumer to be present and view the visualization while the producer constructs it, but it is not possible to save the visualization for later use. However, in systems like Animal (Rößling, 2000) and JAWAA (Pierson and Rodger, 1998), the producer first creates the visualization and it is used later on. There are also systems like Matrix (Korhonen and Malmi, 2002), where both approaches are possible. If the visualization is recorded for later use it should be in some widely–used format. Moreover, the usefulness of a visualization is limited, if consumers need a special viewing program. It is impossible to use such visualizations as parts of Web-Based Learning Environments like JHAVÉ (Naps et al., 2000) or integrate them into hypertextbooks as argued by Ross and Grinder (2002). Thus, we only cover systems that are capable of delivering visualization in some widely used format such as Java applet or Scalable Vector Graphics. Furthermore, there must be some minimum level of interaction between the consumer and the visualization (Rößling and Naps, 2002). Therefore systems that do not offer any control over the visualization have been left out of this study. The paper is organized as follows. Section 2 defines the term effortless and section 3 describes the taxonomy used to characterize the example systems (Animal, JAWAA, Jeliot and Matrix). The evaluation is given in section 4. Finally, section 5 makes conclusions based on the observations and gives some future perspective.

Abstract: WebTheme combines the power of software agent-based information retrieval with visual analytics to provide users with a new tool for understanding web information. WebTheme allows users to both quickly comprehend large collections of information from the Web and drill down into interesting portions of a collection. Software agents work for users to perform controlled harvesting of web material of interest. Visualization and analysis tools allow exploration of the resulting document space. Information spaces are organized and presented according to their topical context. Tools that display how documents were collected by the agents, where they were gathered, and how they are linked further enhance users' understanding of information and its context. WebTheme is a significant tool in the pursuit of the Semantic Web. In particular, it supports enhanced user insight into semantics of large, prestructured or ad-hoc, web information collections.

Abstract: Data visualization is the new technique of data analysis and process, which aims at presenting the data sets with image and graph with the assistance of such methods and techniques as interactions, multi-dimension analysis and data mining. This article firstly introduces the concept of data visualization and its development, and then introduces several types of data visualization techniques and their representative methods used in large data sets. It also covers an analysis and comparison between data visualization and scientific computing visualization. In the end, this article discusses on the future work of data visualization. ;

Abstract: Algorithm Animation.- 1 Algorithm Animation.- Specifying Algorithm Visualizations: Interesting Events or State Mapping?.- Perspectives on Program Animation with Jeliot.- Animating Algorithms Live and Post Mortem.- Visualising Objects: Abstraction, Encapsulation, Aliasing, and Ownership.- Algorithm Animation Using Data Flow Tracing.- GeoWin A Generic Tool for Interactive Visualization of Geometric Algorithms.- Algorithm Animation Systems for Constrained Domains.- Algorithm Animation for Teaching.- Software Engineering.- 2 Software Engineering.- Software Visualization for Reverse Engineering.- Visualizing the Execution of Java Programs.- JaVis: A UML-Based Visualization and Debugging Environment for Concurrent Java Programs.- JAVAVIS: Automatic Program Visualization with Object and Sequence Diagrams Using the Java Debug Interface (JDI).- Visualizing Memory Graphs.- Software Visualization and Education.- 3 Software Visualization and Education.- Structure and Constraints in Interactive Exploratory Algorithm Learning.- A Language and System for Constructing and Presenting Low Fidelity Algorithm Visualizations.- Towards a Taxonomy of Network Protocol Visualization Tools.- Understanding Algorithms by Means of Visualized Path Testing.- Hypertextbooks: Animated, Active Learning, Comprehensive Teaching and Learning Resources for the Web1.- Graphs in Software Visualization.- 4 Graphs in Software Visualization.- On the Visualization of Java Programs.- Graph Drawing Algorithm Engineering with AGD.- An Overview of the GXL Graph Exchange Language.- Call Graph and Control Flow Graph Visualization for Developers of Embedded Applications.- Future Perspectives.- 5 Future Perspectives.- Visualization for the Mind's Eye.- The rube Framework for Personalized 3-D Software Visualization.- Algorithm Explanation: Visualizing Abstract States and Invariants.- Visualisation and Debugging of Decentralised Information Ecosystems.

Abstract: Chemistry is an experimental science whose research subjects are often not directly available within the close dimensions of a time or space. To optimize a particular teaching process or research, it is necessary to visualize phenomena, processes, or objects. Consequently, visualization is significant to problem solving in research and teaching. Visualization is applicable in those situations when it is required to reduce the dimensions of experimental objects to given numbers and values accessible to direct experience. In educational practice, this is related to one of the following situations: (1) the experiment is too long or too short; (2) the dimensions of the examined object are too small or too large; (3) the environment of the experiment is not accessible; (4) the parameters of the experiment or its effects are not directly available to the observer's senses; (5) there is a need for multiple revisions of the experiment; (6) the experiment is difficult to arrange or revise effectively; (7) the experiment is dangerous; (8) the experiment is too expensive; etc. The presentation of models of physicochemical processes and phenomena, models of atoms and molecules, and mechanisms of reaction, as well as experimental data and their mathematical models, provides a basis for considering the formulation of correct conclusions. The appropriate choice of visualization algorithms is decisive of the effectiveness of theoretical analyses. The main aspect of visualization is obviously its application to teaching or research. Thus, the choice of techniques depends on whether it is used for recognition, explanation, memorization, inspiration, or motivation. In research, the importance as well as area of usefulness of three main categories of visualization have also been established. These categories are: illustration—relating to the presentation of an existing picture of object; representation—the presentation of an image assigned to an object; and visualization—related to the presentation of an image created for the object. Research work on preparing means for visualization confirms that, depending on the particular aspect of categorizing visualization, it may be useful, as well, to assign additional criteria such as dimensions, degree, functions, methodological contexts, experimental relationship, and medial effectiveness into visualization. In recent years, at the Institute of Chemical Education of Poznan's Adam Mickiewicz University such research was undertaken. Its main aim was to determine the educational effectiveness of different types of chemical visualizations. Methods for the visualization of chemical issues were developed and a series of original video and animation sequences presenting different aspects of chemical visualization prepared. Interactive Internet instructions sets were produced and methods of visualization categorized. Effectiveness in using different types of chemical visualizations was estimated. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002

Abstract: The amount of information is increasing rapidly all the while the devices with which to access the information are shrinking in size. This leads to a problem of presentation: how to display the growing amounts of information effectively on small displays. This thesis introduces a number of information visualization techniques as solutions to the presentation problem, as well as devices on which the techniques could be used. Further, an evaluation framework is presented, which can be used to assess the suitability of the information visualization techniques for use on the devices in question. The framework draws together the visualization techniques and devices by comparing their corresponding properties. The proposed solutions are evaluated against the framework in the context of two small display devices. As a result, it is found that only one third of the proposed solutions are suitable for use as such on low-end display devices, such as mobile phones. The situation is reversed in the context of high-end display devices, for example handheld computers. In their case only one third of the techniques are found unsuitable for use.