HCI Bibliography Home | HCI Journals | About TOCHI | Journal Info | TOCHI Journal Volumes | Detailed Records | RefWorks | EndNote | Hide Abstracts
TOCHI Tables of Contents: 010203040506070809101112131415161718192021

ACM Transactions on Computer-Human Interaction 9

Editors:Jonathan Grudin
Standard No:ISSN 1073-0516
Links:Table of Contents
  1. TOCHI 2002 Volume 9 Issue 1
  2. TOCHI 2002 Volume 9 Issue 2
  3. TOCHI 2002 Volume 9 Issue 3
  4. TOCHI 2002 Volume 9 Issue 4

TOCHI 2002 Volume 9 Issue 1

Consistency maintenance in real-time collaborative graphics editing systems BIBAKFull-Text 1-41
  Chengzheng Sun; David Chen
Real-time collaborative graphics editing systems allow a group of users to view and edit the same graphics document at the same time from geographically dispersed sites connected by communication networks. Consistency maintenance in the face of concurrent accesses to shared objects is one of the core issues in the design of these types of systems. In this article, we propose an object-level multiversioning approach to consistency maintenance in real-time collaborative graphic editors. This approach is novel in achieving intention preservation and convergence, in preserving the work concurrently produced by multiple users in the face of conflict, and in minimizing the number of object versions for conflict resolution. Major technical contributions of this work include a formal specification of a unique combined effect for an arbitrary group of conflict and compatible operations, a distributed algorithm for incremental creation of multiple object versions, a consistent object identification scheme for multiple object versions, and a convergent layering scheme for overlapping objects. All algorithms and schemes presented in this article have been implemented in an Internet-based GRACE (graphics collaborative editing) system.
Keywords: Collaborative graphics editors, GRACE, computer-supported cooperative work, consistence maintenance, convergence, groupware, intention preservation, multiversioning
The importance of translucence in mobile computing systems BIBAKFull-Text 42-67
  Maria R. Ebling; Bonnie E. John; M. Satyanarayanan
Mobile computing has been an active area of research for the past decade, but its importance will increase substantially in the decade to come. One problem faced by designers of mobile systems is that of maintaining the illusion of connectivity even when network performance is poor or non-existent. The Coda file system uses its cache to maintain this illusion. Extensive experience with the system suggests that, although users find the functionality provided by the system extremely valuable, new users face an arduous learning curve and even experienced users are sometimes confused by the system's behavior. The fundamental problem is that the lack of a strong network connection causes the system to violate a key property of caching: transparency. To overcome this problem, we have built an interface, called the CodaConsole, that makes caching translucent to users through controlled exposure of cache management internals. The interface exposes critical aspects of caching to support the mobile user while hiding noncritical details to preserve usability. This article presents the design, implementation, and usability evaluation of this interface. The CodaConsole successfully makes caching translucent in the presence of disconnected or weakly connected operation. The most surprising result was that novice Coda users performed almost as well as experienced Coda users.
Keywords: operation

TOCHI 2002 Volume 9 Issue 2

Introduction to the new usability BIBAKFull-Text 69-73
  Peter Thomas; Robert D. Macredie
This paper introduces the motivation for and concept of the "new usability" and positions it against existing approaches to usability. It is argued that the contexts of emerging products and systems mean that traditional approaches to usability engineering and evaluation are likely to prove inappropriate to the needs of "digital consumers." The paper briefly reviews the contributions to this special issue in terms of their relation to the idea of the "new usability" and their individual approaches to dealing with contemporary usability issues. This helps provide a background to the "new usability" research agenda, and the paper ends by posing what are argued to be the central challenges facing the area and those which lie at the heart of the proposed research agenda.
Keywords: Internet appliances, design, new usability, ubiquitous computing, usability engineering
The usability of everyday technology: emerging and fading opportunities BIBAKFull-Text 74-105
  Marianne Graves Petersen; Kim Halskov Madsen; Arne Kjaer
Current work in the field of usability tends to focus on snapshots of use as the basis for evaluating designs. However, giving due consideration to the fact that everyday use of technology involves a process of evolution, we set out to investigate how the design of the technology may be used to support this. Based on a long-term empirical study of television use in the homes of two families, we illustrate how use continuously develops in a complex interplay between the users' expectations -- as they are formed and triggered by the design -- and the needs and context of use per se. We analyze the empirical data from the perspective of activity theory. This framework serves to highlight how use develops, and it supports our analysis and discussion about how design, the users' backgrounds, previous experience, and needs, and the specific context of use supports or hinders the development of use. Moreover, we discuss how the characteristics of the home settings, in which the televisions studied were situated, represent a challenge to usability work. The concluding discussion leads to a set of hypotheses relevant to designers and researchers who wish to tackle some of the aspects of usability of particular importance to development in the use of home technology.
Keywords: TV set, activity theory, case study, design, development in use, domestic technology, usability
From use to presence: on the expressions and aesthetics of everyday computational things BIBAKFull-Text 106-124
  Lars Hallnas; Johan Redstrom
The coming ubiquity of computational things urges us to consider what it means for something to be present in someone's life, in contrast to being just used for something. "Use" and "presence" represent two perspectives on what a thing is. While "use" refers to a general description of a thing in terms of what it is used for, "presence" refers to existential definitions of a thing based on how we invite and accept it as a part of our lifeworld. Searching for a basis on which these existential definitions are formed, we argue that the expressions of things are central for accepting them as present in our lives. We introduce the notion of an expressional, referring to a thing designed to be the bearer of certain expressions, just as an appliance is designed to be the bearer of a certain functionality. Aesthetics, as a logic of expressions, can provide a proper foundation for design for presence. We discuss the expressiveness of computational things as depending both on time structures and space structures. An aesthetical leitmotif for the design of computational things -- a leitmotif that may be used to guide a normative design philosophy, or a design style -- is described. Finally, we describe a practical example of what designing a mobile phone as an "expressional" might be like.
Keywords: aesthetics, design, information appliances, phenomenology, ubiquitous computing
Beyond the handset: designing for wireless communications usability BIBAKFull-Text 125-151
  Leysia Palen; Marilyn Salzman
Service-based wireless devices like wireless telephones require users to interact with aspects of the technology beyond the hardware and software of the handset. By entering into contractual relationships with service-providers, and by using network-based services, users interact with a larger system -- one that has social and technological components. The operation of the wireless telephone requires the assimilation of heterogeneous sources of information from the device manufacturer, sales people, customer service representatives, marketing people, and members of the popular media, among others, which can easily confound users' understanding of this new class of technology. Opportunities for usability problems therefore scale beyond the handset, as do opportunities for better design. We report the results of a study of 19 novice wireless phone users who were closely tracked for the first 6 weeks after service acquisition. Taking a technology-as-system analytical approach, we describe the wireless telephony system as four socio-technical components: hardware, software, "netware," and "bizware." This particular organization of the system is intended for the practical application of designing for usability.
Keywords: cell, field study, mobile, qualitative study, social construction of technology, socio-technical systems, usability, wireless telephones
The design collaboratorium: a place for usability design BIBAKFull-Text 152-169
  Susanne Bødker; Jacob Buur
The "design collaboratorium" is a new usability practice that has been developed in an action research project between three industrial usability labs and a university. The design collaboratorium has been developed as a reaction to the failing capabilities of classical usability methods to cope with ubiquitous technologies. It has borrowed elements from participatory design and developed them further to become useful in large-scale industrial development organizations. The design collaboratorium will be presented through examples from a joint project: a vision project concerning wastewater treatment technology. In light of the case, we will discuss the philosophy underlying the design collaboratorium in further detail: the collaboration between active participants, the role of design artifacts, and the room as a meeting ground. Finally we lay out the working method and propose directions for future usability competencies.
Keywords: cooperative design, ubiquitous and mobile technology, usability practice, user interface methodology

TOCHI 2002 Volume 9 Issue 3

Multimodal human discourse: gesture and speech BIBAKFull-Text 171-193
  Francis Quek; David McNeill; Robert Bryll; Susan Duncan; Xin-Feng Ma; Cemil Kirbas; Karl E. McCullough; Rashid Ansari
Gesture and speech combine to form a rich basis for human conversational interaction. To exploit these modalities in HCI, we need to understand the interplay between them and the way in which they support communication. We propose a framework for the gesture research done to date, and present our work on the cross-modal cues for discourse segmentation in free-form gesticulation accompanying speech in natural conversation as a new paradigm for such multimodal interaction. The basis for this integration is the psycholinguistic concept of the coequal generation of gesture and speech from the same semantic intent. We present a detailed case study of a gesture and speech elicitation experiment in which a subject describes her living space to an interlocutor. We perform two independent sets of analyses on the video and audio data: video and audio analysis to extract segmentation cues, and expert transcription of the speech and gesture data by microanalyzing the videotape using a frame-accurate videoplayer to correlate the speech with the gestural entities. We compare the results of both analyses to identify the cues accessible in the gestural and audio data that correlate well with the expert psycholinguistic analysis. We show that "handedness" and the kind of symmetry in two-handed gestures provide effective supersegmental discourse cues.
Keywords: Multimodal interaction, conversational interaction, discourse, gesture, gesture analysis, human interaction models, speech
Cooperative visual manipulation of music notation BIBAKFull-Text 194-237
  P. Bellini; P. Nesi; M. B. Spinu
As computer technologies and their potential emerging applications spread out, new needs have been detected for computer-based applications of music; cooperative music notation editing both in orchestras and music schools is one of them. This article is the only public document describing the details of cooperative work on music notation of MOODS (Music Object Oriented Distributed System). MOODS is a synchronous real-time cooperative editor for music scores. Its architecture includes mechanisms for troubleshooting conflicts in real-time, managing histories of commands and versioning, and for performing selective undo. The system also includes specific solutions in order to control the editing on the account of editing permission profiles. The most important aspects of MOODS associated with cooperative work on music notation scores are reported herein. The article highlights the general problems of cooperative systems and provides rationales for the solutions, which were found to build MOODS. The MOODS system has been implemented and validated thanks to the endeavor of several musicians in orchestras, music schools, and project partners. A prototype has been demonstrated in public at the Scala Theatre in Milan, Italy.
Keywords: Collaboration of music notation editing, additional command list, collaborative systems, computer-supported cooperative work, consistency control, cooperative music, distributed music, electronic lectern, neutral version, selective undo, user interface management systems
Rivalry and interference with a head-mounted display BIBAKFull-Text 238-251
  Robert S. Laramee; Colin Ware
Perceptual factors that affect monocular, transparent (a.k.a "see-thru") head-mounted displays include binocular rivalry, visual interference, and depth of focus. We report the results of an experiment designed to evaluate the effects of these factors on user performance in a table look-up task. Two backgrounds were used. A dynamic moving background was provided by a large screen TV and an untidy bookshelf was used to provide a complex static background. With the TV background large effects were found attributable to both rivalry and visual interference. These two effects were roughly additive. Smaller effects were found with the bookshelf. In conclusion we suggest that monocular transparent HMDs may be unsuitable for use in visually dynamic environments. However when backgrounds are relatively static, having a transparent display may be preferable to having an opaque display.
Keywords: Wearable computing, augmented reality, binocular rivalry, head-mounted display, heads-up display, mobile computing devices, see-thru Display, visual interference

TOCHI 2002 Volume 9 Issue 4

Appendices A--D: A scalable method for deductive generalization in the spreadsheet paradigm BIBFull-Text 1-5
  Margaret Burnett; Sherry Yang; Jay Summet
A scalable method for deductive generalization in the spreadsheet paradigm BIBAKFull-Text 253-284
  Margaret Burnett; Sherry Yang; Jay Summet
In this paper, we present an efficient method for automatically generalizing programs written in spreadsheet languages. The strategy is to do generalization through incremental analysis of logical relationships among concrete program entities from the perspective of a particular computational goal. The method uses deductive dataflow analysis with algebraic back-substitution rather than inference with heuristics, and there is no need for generalization-related dialog with the user. We present the algorithms and their time complexities and show that, because the algorithms perform their analyses incrementally, on only the on-screen program elements rather than on the entire program, the method is scalable. Performance data is presented to help demonstrate the scalability.
Keywords: Forms/3, Human-computer interaction, concrete programming, generalization, graphical programming, spreadsheet languages
Symmetric and asymmetric action integration during cooperative object manipulation in virtual environments BIBAKFull-Text 285-308
  Roy A. Ruddle; Justin C. D. Savage; Dylan M. Jones
Cooperation between multiple users in a virtual environment (VE) can take place at one of three levels. These are defined as where users can perceive each other (Level 1), individually change the scene (Level 2), or simultaneously act on and manipulate the same object (Level 3). Despite representing the highest level of cooperation, multiuser object manipulation has rarely been studied. This paper describes a behavioral experiment in which the piano movers' problem (maneuvering a large object through a restricted space) was used to investigate object manipulation by pairs of participants in a VE. Participants' interactions with the object were integrated together either symmetrically or asymmetrically. The former only allowed the common component of participants' actions to take place, but the latter used the mean. Symmetric action integration was superior for sections of the task when both participants had to perform similar actions, but if participants had to move in different ways (e.g., one maneuvering him/herself through a narrow opening while the other traveled down a wide corridor) then asymmetric integration was superior. With both forms of integration, the extent to which participants coordinated their actions was poor and this led to a substantial cooperation overhead (the reduction in performance caused by having to cooperate with another person).
Keywords: Virtual environments, object manipulation, piano movers' problem, rules of interaction
Undo as concurrent inverse in group editors BIBAKFull-Text 309-361
  Chengzheng Sun
As an important mechanism for error recovery and exploration of alternatives in interactive and collaborative applications, an undo facility should have the capability of undoing any operation at any time. However, supporting undo in collaborative applications is technically challenging and none of the existing group undo solutions is able to offer such a capability. In this article, we contribute an undo solution with such a capability for group text editors. The basic idea is to interpret an undo command as a concurrent inverse operation by means of operational transformation. To cope with the high complexity of group undo, a generic undo framework has been adopted to separate undo policy from the undo mechanism and to separate transformation control algorithms from transformation functions. The proposed undo solution consists of a generic transformation control algorithm that is capable of generating, transforming, and representing valid inverse operations in any context, and a set of transformation functions that are capable of preserving undo-related transformation conditions and properties. Formal proofs are provided to show the correctness of the undo transformation control algorithm in achieving the required undo effect, undo property, and consistency properties. Solutions to the known undo puzzles are provided to show soundness of the transformation functions. A Web-based group text editor REDUCE (REal-time Distributed Unconstrained Cooperative Editing) has been implemented to demonstrate the feasibility and usability of the proposed undo and other technical solutions. The proposed undo solution is generally applicable to collaborative applications that support concurrent insertion and deletion on shared documents consisting of one or multiple dimensions of linearly ordered data objects with positional references.
Keywords: Group undo, REDUCE, collaborative applications, computer-supported cooperative work, concurrency control, consistence maintenance, distributed systems, operational transformation
Navigation patterns and usability of zoomable user interfaces with and without an overview BIBAKFull-Text 362-389
  Kasper Hornbaek; Benjamin B. Bederson; Catherine Plaisant
The literature on information visualization establishes the usability of interfaces with an overview of the information space, but for zoomable user interfaces, results are mixed. We compare zoomable user interfaces with and without an overview to understand the navigation patterns and usability of these interfaces. Thirty-two subjects solved navigation and browsing tasks on two maps. We found no difference between interfaces in subjects' ability to solve tasks correctly. Eighty percent of the subjects preferred the interface with an overview, stating that it supported navigation and helped keep track of their position on the map. However, subjects were faster with the interface without an overview when using one of the two maps. We conjecture that this difference was due to the organization of that map in multiple levels, which rendered the overview unnecessary by providing richer navigation cues through semantic zooming. The combination of that map and the interface without an overview also improved subjects' recall of objects on the map. Subjects who switched between the overview and the detail windows used more time, suggesting that integration of overview and detail windows adds complexity and requires additional mental and motor effort.
Keywords: Information visualization, levels of detail, maps, navigation, overview+detail interfaces, overviews, usability, zoomable user interfaces (ZUIs)