Showing papers presented at "Advanced Visual Interfaces in 2002"

Degree-of-interest trees: a component of an attention-reactive user interface

Abstract: This paper proposes Degree-of-Interest trees. These trees use degree-of-interest calculations and focus+context visualization methods, together with bounding constraints, to fit within pre-established bounds. The method is an instance of an emerging "attention-reactive" user interface whose components are designed to snap together in bounded spaces.

Scope: providing awareness of multiple notifications at a glance

Abstract: We describe the design and functionality of the Scope, a glanceable notification summarizer. The Scope is an information visualization designed to unify notifications and minimize distractions. It allows users to remain aware of notifications from multiple sources of information, including e-mail, instant messaging, information alerts, and appointments. The design employs a circular radar-like screen divided into sectors that group different kinds of notifications. The more urgent a notification is, the more centrally it is placed. Visual emphasis and annotation is used to reveal important properties of notifications. Several natural gestures allow users to zoom in on particular regions and to selectively drill down on items. We present key aspects of the Scope design, review the results of an initial user study, and describe the motivation and outcome of an iteration on the visual design.

Visualization techniques for circular tabletop interfaces

Abstract: This paper presents visualization and layout schemes developed for a novel circular user interface designed for a round, tabletop display. Since all the displayed items are in a polar coordinate system, many interface and visualization schemes must be revisited to account for this new layout of UI elements. We discuss the direct implications of such a circular interface on document orientation. We describe two types of fisheye deformation of the circular layout and explain how to use them in a multi-person collaborative interface. These two schemes provide a general layout framework for circular interfaces. We have also designed a new visualization technique derived from the particularities of the circular layout we have highlighted. In this technique the user controls the layout of the elements of a hierarchical tree. Our approach is to provide the user rich interaction possibilities to easily and quickly produce a layout comparable to the hyperbolic view developed at Xerox PARC. The visualization work presented in this paper is part of our ongoing Personal Digital Historian (PDH) research project. The overall goal of PDH is to investigate ways to effectively and intuitively organize, navigate, browse, present and visualize digital data in an interactive multi-person conversational setting.

VIP: a visual approach to user authentication

Abstract: This paper addresses knowledge-based authentication systems in self-service technology, presenting the design and evaluation of the Visual Identification Protocol (VIP). The basic idea behind it is to use pictures instead of numbers as a means for user authentication. Three different authentication systems based on images and visual memory were designed and compared with the traditional Personal Identification Number (PIN) approach in a longitudinal study involving 61 users. The experiment addressed performance criteria and subjective evaluation. The study and associated design exploration revealed important knowledge about users, their attitudes towards and behaviour with novel authentication approaches using images. VIP was found to provide a promising and easy-to-use alternative to the PIN. The visual code is easier to remember, preferred by users and potentially more secure than the numeric code. Results also provided guidelines to help designers make the best use of the natural power of visual memory in security solutions.

by chance enhancing interaction with large data sets through statistical sampling

Abstract: The use of random algorithms in many areas of computer science has enabled the solution of otherwise intractable problems. In this paper we propose that random sampling can make the visualisation of large datasets both more computationally efficient and more perceptually effective. We review the explicit uses of randomness and the related deterministic techniques in the visualisation literature. We then discuss how sampling can augment existing systems. Furthermore, we demonstrate a novel 2D zooming interface - the Astral Telescope Visualiser, a visualisation suggested and enabled by sampling. We conclude by considering some general usability and technical issues raised by sampling-based visualisation.

Drawing graphs with non-uniform vertices

Abstract: The vertices of most graphs that appear in real applications are non-uniform. They can be circles, ellipses, rectangles, or other geometric elements of varying shapes and sizes. Unfortunately, current force directed methods for laying out graphs are suitable mostly for graphs whose vertices are zero-sized and dimensionless points. It turns out that naively extending these methods to handle non-uniform vertices results in serious deficiencies in terms of output quality and performance. In this paper we try to remedy this situation by identifying the special characteristics and problematics of such graphs and offering several algorithms for tackling them. The algorithms can be viewed as carefully constructed extensions of force-directed methods, and their output quality and performance are similar.

Which interaction technique works when?: floating palettes, marking menus and toolglasses support different task strategies

Abstract: We conducted an experiment that compared three post-WIMP interaction techniques: floating palettes, marking menus and toolglasses, in a real-world Coloured Petri-Net editor, CPN2000. We created six situations in which users performed identical sets of actions with equally-complex nets, but with different cognitive contexts. We found significant differences in performance and preferences across interaction techniques. When a user is in a "copy" context, floating palettes are more efficient. If the user is problem solving, toolglasses or marking menus are preferred. No single interaction technique is clearly superior: each has strengths in different contexts. Since a single application must support different kinds of cognitive tasks, interaction designers should consider integrating multiple interaction techniques, rather than selecting only one.

What did they do? understanding clickstreams with the WebQuilt visualization system

Abstract: This paper describes the visual analysis tool WebQuilt, a web usability logging and visualization system that helps web design teams record and analyze usability tests. The logging portion of WebQuilt unobtrusively gathers clickstream data as users complete specified tasks. This data is then aggregated and presented as an interactive graph, where nodes of the graph are images of the web pages visited, and arrows are the transitions between pages. To aid analysis of the gathered usability test data, the WebQuilt visualization provides filtering capabilities and semantic zooming, allowing the designer to understand the test results at the gestalt view of the entire graph, and then drill down to sub-paths and single pages. The visualization highlights important usability issues, such as pages where users spent a lot of time, pages where users get off track during the task, navigation patterns, and exit pages, all within the context of a specific task. WebQuilt is designed to conduct remote usability testing on a variety of Internet-enabled devices and provide a way to identify potential usability problems when the tester cannot be present to observe and record user actions.

On evaluating information visualization techniques

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.

What's happening?: promoting community awareness through opportunistic, peripheral interfaces

Abstract: Maintaining an awareness of information about one's own community and its members is viewed as being important, but is becoming more challenging today as people are overwhelmed by so many different forms of information. This paper describes the "What's Happening" suite of tools for helping convey relevant and interesting community information to people in a manner that is minimally distracting and disruptive, with little or no user set-up and interaction. The tools are more lightweight than e-mail and Usenet news, and opportunistic in providing information to people when they are not deeply focused on some other task.

Artistically conveying peripheral information with the InfoCanvas

Abstract: The Internet and World Wide Web have made a tremendous amount of information available to people today. Taking advantage of and managing this information, however, is becoming increasingly challenging due to its volume and the variety of sources available. We attempt to reduce this overload with the InfoCanvas, an ambient display of a personalized, information-driven, visual collage. Through a web-based interface, people identify information of interest, associate a pictorial representation with it, and place the representation on a virtual canvas. The end result is an information collage, displayed on a secondary monitor or net appliance, that allows people to keep tabs on information in a calm, unobtrusive manner. This paper presents details on how a person can create and manage information with the InfoCanvas, and how we provide such capabilities.

User-interface design, culture, and the future

Abstract: This paper introduces the cultural anthropologist Hofstede's culture dimensions and considers how they might affect user-interface designs. Examples from the Web illustrate the cultural dimensions User-interface designers have identified basic components of user interfaces. An initial mapping of culture dimensions to user-interface components seeks to help user-interface designers cope with global product and service development. Ultimately, tools might emerge to facilitate tuning designs per culture.

Group-based interface for content-based image retrieval

Abstract: In Content-based Image Retrieval (CBIR) systems, the Query-by-Example (QBE) approach is commonly used. However, because of inevitable "semantic gaps" between visual features and the user's concepts, trial-and-error query is essential for successful retrieval. Unfortunately, traditional user interfaces are not suitable for trying different combinations of query examples. This is because in these systems, query specification and result display are done on the same workspace. Once the user removes an image from the query examples, the image may disappear from the user interface. In addition, it is difficult to combine the result of different queries.In this paper, we propose a new interface for Content-based image retrieval. In our system, the users can interactively compare different combinations of query examples by dragging and grouping images on the workspace (Query-by-Group.) Because the query results are displayed on another pane, the user can quickly review the results. Combining different queries is also easy. Furthermore, the concept of "image groups" is also applied to annotating and organizing a large number of images. Because the gestural operations of our system is similar to file operations of modern window-based operation systems, users can easily learn to use the system.

A user-tracing architecture for modeling interaction with the world wide web

Abstract: We have developed a methodology for studying and analyzing the psychology of users performing ecologically valid WWW tasks. A user trace is a record of all significant states and events in the user-WWW interaction based on eye tracking data, application-level logs, and think-aloud protocols. A user-tracing architecture has been implemented for developing simulation models of user-WWW interaction and for comparing a simulation model (SNIF-ACT) against user-trace data. The user tracing architecture compares each action of the SNIF-ACT simulation directly against observed user actions. The model and architecture have been used to successfully match detailed user trace data from four users working on two tasks each.

The HuGS platform: a toolkit for interactive optimization

Abstract: In this paper we develop a generalized approach to visualizing and controlling an optimization process. Our framework, called Human-Guided Search, actively involves people in the process of optimization. We provide simple and general visual metaphors that allow users to focus and constrain the exploration of the search space. We demonstrate that these metaphors apply to a wide variety of problems and optimization algorithms. Our software toolkit supports rapid development of human-guided search systems.Our approach addresses many often-neglected aspects of optimization that are critical to providing people with practical solutions to their optimization problems. Users need to understand and trust the generated solutions in order to effectively implement, justify, and modify them. Furthermore, it is often impossible for users to specify, in advance, all appropriate constraints and selection criteria for their problem. Thus, automatic methods can only find solutions that are optimal with regard to an invariably over-simplified problem description. In contrast, human-in-the-loop optimization allows people to find and better understand solutions that reflect their knowledge of real-world constraints.Finally, interactive optimization leverages people's abilities in areas in which humans currently outperform computers, such as visual perception, learning from experience, and strategic assessment. Given a good visualization of the problem, people can employ these skills to direct a computer search into the more promising regions of the search space.The software we describe is written in Java and is available under a free research license for research or educational purposes.

Zooming, multiple windows, and visual working memory

Abstract: Zooming and multiple windows are two techniques designed to address the focus-in-context problem. We present a theoretical model of performance that models the relative benefits of these techniques when used by humans for completing a task involving comparisons between widely separated groups of objects. The crux of the model is its cognitive component: the strength of multiple windows comes in the way they aid visual working memory. The task to which we apply our model is multiscale comparison, in which a user begins with a known visual pattern and searches for an identical or similar pattern among distracters. The model predicts that zooming should be better for navigating between a few distant locations when demands on visual memory are low, but that multiple windows are more efficient when demands on visual memory are higher, or there are several distant locations that must be investigated. To evaluate our model we conducted an experiment in which users performed a multiscale comparison task using both zooming and multiple-window interfaces. The results confirm the general predictions of our model.

Matrix: concept animation and algorithm simulation system

Abstract: Data structures and algorithms include abstract concepts and processes, which people often find difficult to understand. Examples of these are complex data types and procedural encoding of algorithms. Software visualization can significantly help in solving the problem.In this paper we describe the platform independent Matrix system which combines algorithm animation with algorithm simulation, where the user interacts directly with data structures through a graphical user interface. The simulation process created by the user can be stored and played back in terms of algorithm animation. In addition, existing library routines can be used for creating illustrations of advanced abstract data types, or for animating and simulating user's own algorithms. Moreover, Matrix provides an extensive set of visual concepts for algorithm animation. These concepts include visualizations for primitive types, arrays, lists, trees, and graphs. This set can be extended further by using arbitrarily nested visualizations

New directions for the design of virtual reality interfaces to e-commerce sites

Abstract: Virtual Reality (VR) interfaces to e-commerce sites have recently begun to appear on the Internet, promising to make the e shopping experience more natural, attractive, and fun for customers. Unfortunately, switching to a desktop VR design for an e-commerce site is not trivial and does not guarantee at all that the interface will be effective. In this paper, we first briefly discuss the potential advantages of these interfaces, stressing the need for a better approach to their design. Then, we present the directions we are following to build more usable and effective VR stores, i.e.: (i) reformulating design guidelines from real-world stores in the VR context, (ii) exploiting VR to create user empowerments that meet both customer and merchant needs, and (iii) personalizing the VR store to better reflect customer's taste, preferences, and interests. For each of the three directions, we illustrate and discuss a detailed case study.

Supporting co-evolution of users and systems by the recognition of interaction patterns

Abstract: This paper presents an approach to support the designer of Visual Interactive Systems (VISs) in adapting a VIS to the evolution of its users. This process is called co-evolution of users and systems. The approach is based on the identification of the patterns of interaction between the user and an interactive system and on their use for the evolution of the system to facilitate novel usages introduced by the user. The approach is focused on WIMP systems and is based on the recently introduced PCL (Pictorial Computing Laboratory) model of interaction, within which we provide a novel definition of interaction pattern. The proposal assumes that the VIS is observed by an external system called SIC (Supporting Interaction Co-evolution), which is in charge of recording the interactions between the user and the VIS and of analyzing the relevant interaction patterns. In particular, SIC exploits a UML-based statechart specification of the VIS in order to associate observed user activities with the states of the interactive process. This information provides a useful basis for a variety of pattern recognition techniques. Two techniques called usual state and recurrent sequence recognition are illustrated and the results of a first experiment are discussed.

Modeling biological reactivity: statecharts vs. Boolean logic

Abstract: Remarkable progress in various fields of biology is leading in the direction of a complete map of the building blocks of biological systems. There is broad agreement among researchers that 21st century biology will focus on attempting to understand how component parts collaborate to create a whole. It is also well agreed that this transition of biology from identifying the building blocks (analysis) to integrating the parts into a whole (synthesis) should rely on the language of mathematics. In a recent publication, we described the results of a first attempt at confronting the above challenge using the visual formalism of statecharts. We presented a detailed model for T cell activation using statecharts within the general framework of object-oriented modeling. In this work, we compare the statechart-based modeling approach to a Boolean formalism presented by Thomas & D'Ari. This comparison was done by taking a model for T cell activation and anergy, which was constructed by Kaufman et al. using such a Boolean formalism, and translating it into the language of statecharts. Comparing these two representations of the same phenomena allows us to assess the advantages and disadvantages of each modeling approach. We believe that the results of this work, together with the results of our previous modeling work on T cell activation, should encourage the use of visual formalisms such as statecharts for modeling complex biological systems.A full version of this paper appeared in the proceedings of the Second International Conference on Systems Biology, Pasadena, CA, USA, 2001 [9].

A framework for designing fisheye views to support multiple semantic contexts

Abstract: In this paper we discuss the design and use of fisheye view techniques to explore semantic relationships in information. Traditional fisheye and "focus + context" techniques dynamically modify the visual rendering of data in response to the changing interest of the user. "Interesting" information is shown in more detail or visually emphasized, while less relevant information is shown in less detail, de-emphasized, or filtered. These techniques are effective for navigating through large sets of information in a constrained display, and for discovering hidden relationships in a particular representation. An open area of research with these techniques, however, is how to redefine interest as a user's tasks and information needs change.We are developing a framework for implementing fisheye views to support multiple semantic contexts. The framework is based on two components: Degree Of Interest functions, and visual emphasis algorithms to change the representation of information with respect to interest. The framework supports different contexts through the aggregation of multiple weighted distance metrics in the calculation of interest.Using this framework, we have developed a user-configurable interface for browsing tabular data that visually emphasizes objects with respect to different semantic contexts.

Biological storytelling: a software tool for biological information organization based upon narrative structure

Abstract: The main task of molecular biologists seeking to understand the molecular basis of disease is identifying and interpreting the relationships of genes, proteins, and pathways in living organisms. While emerging technologies have provided powerful analysis tools to this end, they have also produced an explosion of data, which biologists need to make sense of. We have built software tools to support the synthesis activities of molecular biologists, in particular the activities of organizing, retrieving, using, sharing, and reusing diverse biological information. A key aspect of our approach, based upon the findings of user studies, is the use of narrative structure as a conceptual framework for developing and representing the "story" of how genes, proteins, and other molecules interact in biological processes. Biological stories are represented both textually and graphically within a simple conceptual model of items, collections, and stories.

Expressiveness of the data flow and data state models in visualization systems

Abstract: 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.

Patterns of eye gaze during rapid serial visual presentation

Abstract: The technique of Rapid Serial Visual Presentation (RSVP), comparable with the riffling of a book's pages to acquire an impression of its contents, has considerable application potential, especially where display space is at a premium. The design of RSVP applications, however, is not straightforward in view of the many, and often conflicting, design decisions that must be taken. Specifically, it is suspected that many of these decisions will impact on the ability of users to effectively perceive the displayed content as far as carrying out a task is concerned. This paper presents an exploratory study in which we investigated the impact of a number of design decisions on users' eye movements. Four RSVP modes were implemented that represent alternative design decisions. Two of these modes were modeled after existing e-commerce applications, and two have been the subject of our ongoing research for some time. For each RSVP mode, a set of images was presented to two participants who were required to respond to the appearance of a pre-viewed target image. In the course of these presentations we recorded the participants' eye movements in order to elicit information concerning potential perceptual difficulties. We propose a novel graphical characterization of RSVP modes, which is appropriate to their correlation with recorded eye gaze patterns, offer an interpretation of the experimental data, and provide a motivation for further research into RSVP.

Two-handed drawing on augmented desk system

Abstract: This paper describes a two-handed drawing tool developed on our augmented desk system. Using our real-time finger tracking method, a user can draw and manipulate objects interactively by his/her own finger/hand. Based on the former work on two-handed interaction, different roles are assigned to each hand. The right hand is used to draw and to manipulate objects. Using gesture recognition, primitive objects can be drawn by users' handwriting. On the other hand, the left hand is used to manipulate menus and to assist the right hand. By closing all left hand fingers, users can initiate the appearance of structural radial menus around their left hands, and can select appropriate items by using a left hand finger. The left hand is also used to assist in the performance of drawing tasks, e.g., specifying the center of a circle or top-left corner of a rectangle, or specifying the object to be copied.

OZONE: a zoomable interface for navigating ontology information

Abstract: We present OZONE (Zoomable Ontology Navigator), for searching and browsing ontological information. OZONE visualizes query conditions and provides interactive, guided browsing for DAML (DARPA Agent Markup Language) ontologies on the Web. To visually represent objects in DAML, we define a visual model for its classes, properties and relationships between them. Properties can be expanded into classes for query refinement. The visual query can be formulated incrementally as users explore class and property structures interactively. Zoomable interface techniques are employed for effective navigation and usability.

A web-based annotation tool supporting e-learning

Abstract: A typical user, when learning, annotates text, figures and other contents, so as to better highlight, memorize, and retrieve relevant information. A few annotation programs exist but either change the contents of the document, or do not support distance learning through the web. We report work-in-progress on a user-centered annotation tool (UCAT) which allows students to annotate, following their personal styles, (using different icons, colors and signed versions) any document belonging to authorware within a course. We have chosen Amaya as the working environment since, belonging to the World Wide Web Consortium (W3C), it complies with the semantic web specifications on document formats, like RDF. An example of the deployment of UCAT will be shown in the paper.

Reflections on symmetry

Abstract: Symmetry is routinely used in visual design, but in fact is not just a visual concept. This paper explores how deeper symmetries in user interface implementations can be 'reflected' in the design of the user interface, and make them easier to use. This deeper application of symmetry for user interface design is related to affordance, and therefore makes that concept constructively applicable. Recommendations for programming better user interfaces are suggested."Symmetry, as wide or as narrow as you may define its meaning, is one idea by which man through the ages has tried to comprehend and create order, beauty, and perfection." Hermann Weyl [16]

A method for the perceptual optimization of complex visualizations

Abstract: A common problem in visualization applications is the display of one surface overlying another. Unfortunately, it is extremely difficult to do this clearly and effectively. Stereoscopic viewing can help, but in order for us to be able to see both surfaces simultaneously, they must be textured, and the top surface must be made partially transparent. There is also abundant evidence that all textures are not equal in helping to reveal surface shape, but there are no general guidelines describing the best set of textures to be used in this way. What makes the problem difficult to perceptually optimize is that there are a great many variables involved. Both foreground and background textures must be specified in terms of their component colors, texture element shapes, distributions, and sizes. Also to be specified is the degree of transparency for the foreground texture components. Here we report on a novel approach to creating perceptually optimal solutions to complex visualization problems and we apply it to the overlapping surface problem as a test case. Our approach is a three-stage process. In the first stage we create a parameterized method for specifying a foreground and background pair of textures. In the second stage a genetic algorithm is applied to a population of texture pairs using subject judgments as a selection criterion. Over many trials effective texture pairs evolve. The third stage involves characterizing and generalizing the examples of effective textures. We detail this process and present some early results.

Knowledge-supported graphical illustration of texts

Abstract: We introduce a new method to automatically and dynamically illustrate arbitrary texts from a predefined application domain. We demonstrate this method with two experimental systems (Text Illustrator and Agi3le) which are designed to illustrate anatomy textbooks.Both systems exploit a symbolic representation of the content of structured geometric models. In addition, the approach taken by the Agi3le-system is based on an ontology providing a formal representation of important concepts within the application domain as well as a thesaurus containing alternative linguistic and visual realizations for entities within the formal domain representation.The presented method is text-driven, i.e., an automated analysis of the morphologic, syntactic and semantic structures of noun phrases reveals the key concepts of a text portion to be illustrated. The specific relevance of entities within the formal representation is determined by a spreading activation approach. This allows to derive important parameters for a non-photorealistic rendering process: the selection of suitable geometric models, camera positions and presentation variables for individual geometric objects. Part-whole relations are considered to assign visual representations to elements of the formal domain representation. Presentation variables for objects in the 3D rendering are chosen to reflect the estimated relevance of their denotation.As a result, expressive non-photorealistic illustrations which are focussed on the key concepts of individually selected text passages are generated automatically. Finally, we present methods to integrate user interaction within both media, the text and the computer-generated illustration, in order to adjust the presentation to individual information seeking goals.