Showing papers presented at "Advanced Visual Interfaces in 1998"

Augmented reality: linking real and virtual worlds: a new paradigm for interacting with computers

Abstract: A revolution in computer interface design is changing the way we think about computers Rather than typing on a keyboard and watching a television monitor, Augmented Reality lets people use familiar, everyday objects in ordinary ways The difference is that these objects also provide a link into a computer network Doctors can examine patients while viewing superimposed medical images; children can program their own LEGO constructions; construction engineers can use ordinary paper engineering drawings to communicate with distant colleagues Rather than immersing people in an artificially-created virtual world, the goal is to augment objects in the physical world by enhancing them with a wealth of digital information and communication capabilities

Starting simple: adding value to static visualisation through simple interaction

Abstract: Interactive visualisation has been one of the most exciting areas in HCI over recent years. The key term here is 'interactive', and in this paper we assert that virtually any static representation can become more powerful by the addition of simple interactive elements. This is demonstrated by adding interactivity to standard representations including stacked histograms, pie charts and scatter plots. We show how adding interactivity can help resolve many of the trade-offs inherent in static visualisations by allowing multiple options to be available and most importantly for them to be interactively related. Many years of creativity and effort have been invested in traditional generic and bespoke visualisations. Adding interactivity leverages this accumulated experience, but also adds an extra dimension.

Remote evaluation for post-deployment usability improvement

Abstract: Although existing lab-based formative evaluation is frequently and effectively applied to improving usability of software user interfaces, it has limitations that have led to the concept of remote usability evaluation. Perhaps the most significant impetus for remote usability evaluation methods is the need for a project team to continue formative evaluation downstream, after deployment.The usual kinds of alpha and beta testing do not qualify as formative usability evaluation because they do not yield detailed data observed during usage and associated closely with specific task performance. Critical incident identification is arguably the single most important source of this kind of data. Consequently, we developed and evaluated a cost-effective remote usability evaluation method, based on real users self-reporting critical incidents encountered in real tasks performed in their normal working environments. Results show that users with only brief training can identify, report, and rate the severity level of their own critical incidents.

Constant information density in zoomable interfaces

Abstract: We introduce a system that helps users construct interactive visualizations with constant information density. This work is an extension of the DataSplash database visulaization environment. DataSplash is a direct manipulation system in which users can construct and navigate visualizations. Objects' appearances change as users zoom closer to or further away from the visualization. Users specify graphically the point at which these changes occur.Our experience with DataSplash indicates that users find it difficult to construct visualizations that display an appropriate amount of detail. In this paper, we introduce an extension to DataSplash based on the Principle of Constant Information Density. This extension gives users feedback about the density of visualizations as they create them. We also introduce an extension that suggests improvements to existing visualizations.We have performed an informal study of user navigation in applications with and without constant information density. We suggest that designers take density into account when designing applications to avoid biasing user navigation in unexpected ways.

Kaleidoquery: a visual query language for object databases

Abstract: In this paper we describe Kaleidoquery, a visual query language for object databases with the same expressive power as OQL. We will describe the design philosophy behind the filter flow nature of Kaleidoquery and present each of the language's constructs, giving examples and relating them to OQL. The Kaleidoquery language is described independent of any implementation details, but a brief description of a 3D interface currently under construction for Kaleidoquery is presented. The queries in this implementation of the language are translated into OQL and then passed to the object database O2 for evaluation.

Dynamic key frame presentation techniques for augmenting video browsing

Abstract: Because of unique temporal and spatial properties of video data, different techniques for summarizing videos have been proposed. Key frames extracted directly from video inform users about content without requiring them to view the entire video. As part of ongoing work to develop video browsing interfaces, several interface displays based on key frames were investigated. Variations on dynamic key frame "slide shows" were examined and compared to a static key frame "filmstrip" display. The slide show mechanism displays key frames in rapid succession and is designed to facilitate visual browsing by exploiting human perceptual capabilities. User studies were conducted in a series of three experiments. Key frame display rate, number of simultaneous displays, and user perception were investigated as a function of user performance in object recognition and gist determination tasks. No significant performance degradation was detected at display rates up to 8 key frames per second, but performance degraded significantly at higher rates. Performance on gist determination tasks degraded less severely than performance on object recognition tasks as display rates increased. Furthermore, gist determination performance dropped significantly between three and four simultaneous slide shows in a single display. Users generally preferred key frame filmstrips to dynamic displays, although objective measures of performance were mixed. Implications for visual interface design and further questions for future research are provided.

Constraint-based graphical layout of multimodal presentations

Abstract: When developing advanced multimodal interfaces, combining the characteristics of different modalities such as natural language, graphics, animation, virtual realities, etc., the question of automatically designing the graphical layout of such presentations in an appropriate format becomes increasingly important. So, to communicate information to the user in an expressive and effective way, a knowledge-based layout component has to be integrated into the architecture of an intelligent presentation system. In order to achieve a coherent output, it must be able to reflect certain semantic and pragmatic relations specified by a presentation planner to arrange the visual appearance of a mixture of textual and graphic fragments delivered by mode-specific generators. In this paper we will illustrate by the example of LayLab, the layout manager of the multimodal presentation system WIP, how the complex positioning problem for multimodal information can be treated as a constraint satisfaction problem. The design of an aesthetically pleasing layout is characterized as a combination of a general search problem in a finite discrete search space and an optimization problem. Therefore, we have integrated two dedicated constraint solvers, an incremental hierarchy solver and a finite domain solver, in a layered constraint solver model CLAY, which is triggered from a common metalevel by rules and defaults. The underlying constraint language is able to encode graphical design knowledge expressed by semantic/pragmatic, geometrical/topological, and temporal relations. Furthermore, this mechanism allows one to prioritize the constraints as well as to handle constraint solving over finite domains. As graphical constraints frequently have only local effects, they are incrementally generated by the system on the fly. Ultimately, we will illustrate the functionality of LayLab by some snapshots of an example run.

Information foraging models of browsers for very large document spaces

Abstract: Information Foraging (IF) Theory addresses user strategies and technology for seeking, gathering, and using on-line information. We present IF-based models and evaluations of two interfaces: the Scatter/Gather browser for large document collections, and the Butterfly interface for surfing the citation link structure of scientific literatures. A computational cognitive model, ACT-IF, models observed users by assuming that they have heuristics that optimize their information foraging behavior in accordance with IF theory.

Design method of interaction techniques for large information spaces

Abstract: Our work focuses on the design of interaction techniques for large information spaces. Our goal is not to define yet another visualization technique but to provide insights for the design of such techniques. Our design approach is based on ergonomic criteria that arose from a study of how the user perceives and manipulates a large information space. We then provide design rules that should help the designer in devising an interaction technique that verifies the ergonomic criteria. After the design of the interaction technique, the next step is software design. We establish links between our design rules/ergonomic criteria and the software architecture model. By applying our PAC-Amodeus model, we show how the software architecture model helps to either verify or assess the ergonomic criteria. We therefore adopt a predictive evaluation approach to the design of interaction techniques for large information spaces. We illustrate our design approach and results through our VITESSE system.

Visual display, pointing, and natural language: the power of multimodal interaction

Abstract: This paper examines user behavior during multimodal human-computer interaction (HCI). It discusses how pointing, natural language, and graphical layout should be integrated to enhance the usability of multimodal systems. Two experiments were run to study simulated systems capable of understanding written natural language and mouse-supported pointing gestures. Results allowed to: (a) develop a taxonomy of communication acts aimed at identifying targets; (b) determine the conditions under which specific referent identification strategies are likely to be produced; (c) suggest guidelines for designing effective multimodal interfaces; (d) show that performance is strongly influenced by interface graphical layout and by user expertise. Our study confirms the value of simulation as a tool for building HCI models and supports the basic idea that linguistic, visual, and motor cues can be integrated to favor effective multimodal communication.

Rapid-fire image previews for information navigation

Abstract: In this paper we consider the role of rapid-fire presentation of images in the service of navigation in information spaces. We presume a model of information navigation in which the user performs a cycle of (pre)viewing, selecting, and moving. Our hypothesis is that images presented to the user in rapid succession can significantly enhance the previewing step, thus optimizing the selection step and improving navigability. We discuss two prototypes for navigation tools in Web information spaces in which images are used as the primary means for presenting meta-information about "upcoming" Web pages. The presentation is modeled as a flow of information streaming to the user, and orientation is visualized through positions in ordered sequences.

The craft of movement in interaction design

Abstract: Interaction designers don't often discuss the aesthetics of movement in digital media. There is no vocabulary nor method---as there is for color and typography---to use in the generation or evaluation of digital compositions. Dewey offers us a philosophical aesthetic towards the communicative experience of art. His abstract theory provides the inspiration to create a practical method for designers of interactive media in a realistic design context. To build the bridge from abstraction to application I have turned to literature that analyzes the aesthetics of movement in visual arts, particularly for vocabularies of both formal and expressive movement qualities. Both vocabularies explore how we map our 3-D kinetic experience to make sense of 2-D qualities in artifacts. Isolated sets of kinetic qualities, as single mappings between experience and formal and expressive movement qualities, are identified. Communication design is comprised of large clusters of these mappings. This method of movement analysis provides the designer with a set of tools to control movement through the manipulation of its properties, both formal and expressive, thereby acting as a conduit that generates the link between designer, artifact, and viewer experience. Building blocks needed to create a communicative system and provide a method for practitioners to analyze and apply movement appropriately in digital compositions are presented. I conclude by briefly sketching how integration might be plausibly gauged by applying the vocabularies to examples of both static and kinetic compositions.

Intelligent visualization and dynamic manipulation: two complementary instruments to support data exploration with GIS

Abstract: To analyze spatially referenced data, i.e. data referring to geographical objects or locations, one should present them on a map. IRIS is a software system that supports exploration of such data by providing two main services: 1) automated generation of maps and 2) interactive facilities to dynamically manipulate the maps. Automated mapping is enabled by incorporation of generic knowledge on map design. This prevents errors in map design resulting in useless or even misleading presentations. It also helps save users' time and efforts as compared to data visualization with the existing mapping software.Unlike paper maps, a map on the computer screen can dynamically change in response to various interactive manipulations. It is possible to design such interactive operations that will significantly promote data exploration. Within IRIS project we develop for each data presentation method a specific interactive tool that exploits the peculiarities of this method and facilitates fulfilling the analysis tasks the method is best suitable for.Currently researches in automated data visualization design and in dynamic manipulation are developed separately whereas these are two complementary instruments to support data exploration. In this paper we show how we integrate these two instruments in IRIS.

Comparing MMVIS to a timeline for temporal trend analysis of video data

Abstract: Our MultiMedia Visual Information Seeking (MMVIS) environment provides an exploratory visual paradigm for temporal trend analysis. In this paper, we present the results of a user interface study evaluating the utility of MMVIS. We compare MMVIS to a timeline-based approach for analyzing temporal trends in real video data. We evaluate the quantity, complexity and accuracy of temporal trend observations made within each interface, compare the number of positive versus negative trends found, and collect feedback on user satisfaction. Our results show that subjects made interesting and complex observations of temporal trends using either interface. The results also indicate some advantages and biases of each interface, such as 1) timeline subjects make more errors during analysis and 2) timeline subjects are biased against identifying negative trends such as exceptions. At the same time, however, subjects appreciate the familiarity of timelines. Because we designed the MMVIS architecture to provide users with a library of visualizations, we thus include a discussion on enhancing the utility of MMVIS through incorporating a timeline into it in the future.

Model-based heuristic evaluation of hypermedia usability

Abstract: This paper presents a systematic approach to the heuristic evaluation of hypermedia that specifically addresses the peculiar features of this class of systems. We propose a set of hypermedia-specific usability attributes and define general "patterns of evaluation activities" called abstract tasks that can be performed by usability experts to check such attributes systematically. The usage of abstract tasks makes application inspection more effective, since it guides the work of evaluators and supports standardization across different evaluators. Our approach is model-based since we use a hypermedia design model (HDM) to identify the constituents of an application that represent the "focus of interest" for the evaluation, to decompose general usability principles into hypermedia-specific attributes, and finally to formulate abstract tasks in a precise way. To show the effectiveness of our method, we discuss the most significant usability problems discovered in eight commercially available hypermedia CD-ROM's.

Towards a distributed 3D virtual museum

Abstract: The paper addresses the problem of the representation of three-dimensional works of art (e.g. sculptures, architectural elements, vases, etc.) in a web-based environment. Specifically, we propose a system for the visual presentation of the 3D results of a standard SQL query to distributed archives. The system solves the general problem of the remote visualization of dynamic result sets on the Internet using standard and low cost processing architectures. It provides the user with an innovative visual metaphor for the analysis and investigation of the objects presented. Moreover, the system has been designed to provide capabilities which go beyond visualization (e.g. manipulation), and further extensions are possible. We describe the methodologies used for the acquisition, storing, and manipulation of 3D artistic objects together with details on the system's implementation in a web environment, using the VRML2.0 specification language.

Figure captions in visual interfaces

Abstract: We present a general concept for the enhancement of visual interfaces with automatic figure captions describing a visualization. The incorporation of figure captions in interactive systems raises some fundamentally new questions as these images are exposed to changes. The dynamic aspects to be considered include the update and customization of figure captions.We employ figure captions not only for the description of images but also for their modification leading to the introduction of interactive figure captions. A general architecture is developed and comprehensively described referring to two application domains: medical illustrations and geographic maps.

Design of multimedia semantic presentation templates: options, problems and criteria of use

Abstract: This paper presents and discusses the use of Semantic Multimedia Presentation Templates which capture presentation structures that are suitable for communicating semantic data relationships occurring across many applications. The identification of the space of the possible presentation templates along with criteria to evaluate them that depend on the current task, data cardinality and other aspects, is very useful for supporting the automatic generation of effective query result multimedia presentations.

Visual representation of hypermedia links according to their types

Abstract: In this paper, we present the first results of the HyperNavi project which is dedicated to the conception of tools to help users navigating in hypermedia systems and thus fight against the two well-known drawbacks: disorientation and cognitive overhead.To this end, we suggest providing users with useful information about links in the interface of such systems. So, in this paper, we discuss the two following points:1. What information or link types are relevant for users whenever they browse hypermedia systems such as the World Wide Web (WWW)?2. What are practical ways to provide visually this information through the interface of such systems? We list different possibilities (text appearance, button, icon, cursor, sound, tooltip, textfield of the status bar, preview and description windows) and make suggestions for a particular domain: the minutes of the Belgian Parliament sessions.

Multimodal communication between synthetic agents

Abstract: Dialoging with a synthetic agent is a vast research topic to enhance user-interface friendliness. We present in this paper an on-going project on the simulation of a dialog situation between two synthetic agents. More particularly we focus our interest on finding the appropriate facial expressions of a speaker addressing to different types of listeners (tourist, employee, child, and so on) using various linguistic forms such as request, question, information. Communication between speaker and listener involves multimodal behaviors such as the choice of words, intonation and paralinguistic parameters for the vocal ones; facial expressions, gaze, gesture and body movements for the non-verbal ones. The choice of each individual behavior, their mutual interaction and synchronization produce the richness and subtility of human communication.In order to develop a system that computes automatically the appropriate facial and gaze behaviors corresponding to a communicative act for a given speaker and listener, our first step is to categorize facial expressions and gaze based on their communicative functions rather than on their appearance. The next step is to find inference rules that describe the "mental" process ongoing in the speaker while communicating with the listener. The rules take into account the power relation between speaker and listener and the beliefs the speaker has about the listener to constrain the choice of performative acts.

Designing GUIs by sketch drawing and visual programming

Abstract: This paper presents a new interactive UIDE that is based on visual programming and constrained sketch drawing. At the early stages of the iterative conception process, GUIs are interactively designed by drawing a "rough sketch" that acts as a first draft of the final description. This drawing is interpreted in real time by the system in order to produce the corresponding widget view (i.e. the actual visible GUI) and a graph of abstract objects that represents the GUI structure. This graph can then be easily modified by mixing visual and textual programming in a fully iterative and incremental way. This system is also based on the use of generic objects which are dynamically instantiated into actual widgets according to their structural and functional context. This scheme makes it possible to define very generic GUIs that can then be deeply refined in an efficient way at any stage of the conception process.

Automatic graphical abstraction in intent-based 3D-illustrations

Abstract: The purpose of this paper is to present models, methods and techniques to control automatically the degree of details in graphics or animation in an intelligent way. Instead of just aiming at the technical advantages of such a reduction (i.e. saving computer memory and computational load), this work focuses on clarifying the intention of graphics or animation with the means of abstraction. The goal is to direct the viewer's attention to relevant parts of the graphics, without using metaobjects or - colours (e.g. arrows, blinking objects etc.) and to reduce the probability of distracting the viewer's attention by unimportant details.The paper describes the major problems of this task and provides a knowledge-based solution to yield an intelligent control of the level of detail, improving the expressivity of the graphics or animation and saving computational resources at the same time. To emphasize the plausibility of these ideas the graphical abstraction system ARP is presented and its results are discussed.

Linking surface error characteristics to root problems in user-based evaluation studies

Abstract: This paper reports a study of novice subjects using Word 5.1. for the Macintosh. In particular, user errors were analysed. The intention was to investigate the difficulty, that evaluators have in determining root error causes from surface characteristics. Errors made by subjects were examined and classified in phenotype and genotype categories[3]. An error was classified in a genotype category if it was felt that system had failed to support that particular user mental action. The utility of the analysis that was used for analysing usability errors is then discussed.

A completely visual environment for agent-based computing

Abstract: A visual environment for end-user visual programming and computing with populations of agents is presented.

Manipulating concept maps with constrained regions

Abstract: This paper addresses the direct manipulation of concept maps. These maps are visually supported by graph-based diagrams. Constraints on nodes, visual attributes and arcs, reflect the syntax and semantic of the underlying conceptual model. Tools allowing the manipulation of concept maps convey these constraints by offering simple feedback hints to user actions. Particular application domains require the use of spatial regions (contexts) to convey equivalence on concept properties or types. In these cases, further restrictions are imposed. Therefore, richer feedback must be supported for effective direct manipulation.The paper proposes an approach to handle spatial contexts in concept maps. The approach provides means to define enhanced feedback on direct manipulation of concepts and relations within and over context boundaries. The technique is based on the separtion of the feedback representations for device and action. It controls their relative distance, mobility and visual attributes. Manipulation of contexts and simultaneous views over contexts are also discussed. Specific behaviors are proposed and a technique to offer coherent views on multiple contexts is presented. The architecture of the system that supports these features is described.

Selected ingredients in end-user programming

Abstract: In the area of human computer interaction, over the last twenty years, we have witnessed considerable progress in an ever-increasing bandwidth from the computer to the user. Application screens evolved from static text only screens to interactive GUI screens. These screens contain numerous graphical element or "widgets", supporting multiple data types, such as text, voice, image, and video. The widgets can range from simple ones like a combo box or slider to more complicated OCX's such as interactive graphs or maps.On the other hand, the tools to program this application are still in the domain of programmers. Although there has been much progress in various RAD tools, visual language and 4GL to improve ease of use, they still mostly target programmers. We believe that in order to allow end-users to develop their own advanced UI applications, it is necessary to create higher-level application abstractions or 'algebra' for stating the application in a declarative manner. This can be compared to the relational algebra operators in the data base area. They were created as abstractions for data base queries, enabling end users to express their own queries in a declarative manner. In doing so, bugs are minimized and program modifications and maintenance becomes trivial. In this paper, we will motivate the reader to see the need for these abstractions and classify them into categories, emphasizing areas ripe for further research.

Engineering the usability of visual formalisms: a case study in real time logics

Abstract: A visual formalism for the presentation of a real time logic is introduced, motivated, and evaluated.The visual formalism has been designed following a user-centered usability engineering process, targeted to the students of higher education courses in software engineering. On the one hand, heuristic design was applied to maximize consistency, i.e. to minimize the complexity of the visual metaphor mapping textual sentences to the visual representation. On the other hand, individual metaphoric assumptions were defined by prototyping and exposing alternative graphical representations to a representative sample of the target community of expected users.The resulting notation has been implemented within an interactive syntax-directed editor which integrates the visual presentation with the conventional textual notation. The editor has been used to carry out a competitive user-based evaluation of the usability of textual and visual representations, by carrying out a readability test on a larger sample of representative end-users.

VisTool: a visual tool for querying relational databases

Abstract: In this paper we describe VisTool, a prototype tool for querying relational databases by means of the visual query language VISIONARY.

"Thin" vs. "fat" visualization clients

Abstract: A thin client, by definition, have minimal software requirements necessary to function as a user interface front-end for a Web enabled application and raises the issue of client vs. server data visualization rendering. Real-time visual data manipulation doesn't translate well into a "thin" client. While the VRML file format allows distribution of visualization scenes to the Web, the user has no access to the actual underlying data source. The "mapping" of numerical data into geometry format (VRML) takes place at the server side.Local data manipulation, information drill-down technique, context sensitive menus, object picking and other interactive user interface functions that traditionally have been available on the client are now controlled by the visualization server. In the "thin" client model, nearly all functionality is delivered from the server side of the visualization engine while the client perform very simple display and querying functions.Web components and Plug-ins are now being used to overcome some of these limitations. Java allows the creation of "applets" and "JavaBeans" and we have Windows/COM components. These components together with data reduction methods can significantly increase the data interaction between the client application and user, and allow tasks to be executed on the client. Highly interactive user interface tasks are delivered that provide point-and-click navigation through multidimensional data structures. Visual data interfaces such as information drilling, moving a cutting plane through a volume data set etc can be supported.The implication of using a static VRML environment with reduced geometry is compared to sending compressed data to the client and perform interactive client data visualization on a desktop.

SIAMOA: a system for visual programming, program visualisation and debugging

Abstract: The paper presents SIAMOA, a system dedicated for design, debugging and visualisation of algorithms. It combines elements of an algorithm visualisation system and an environment for visual programming. Programs may be created graphically by connecting modules represented in form of icons. Individual modules correspond either to sequences of operations written in a traditional, textual form, or to complex blocks of operations created graphically. The main concern of the visualisation of the algorithm execution process is data visualisation; it may be done as a basic or a synthetic one. The architecture of the visualisation engine has been designed with use of the P. Os.T. model, previously used to build interactive platforms for simulation of industrial processes.