Robert S. Fish

The VideoWindow system in informal communication

Imagine sitting in your work place lounge having coffee with some colleagues. Now imagine that you and your colleagues are still in the same room, but are separated by a large sheet of glass that does not interfere with your ability to carry on a clear, two-way conversation. Finally, imagine that you have split the room into two parts and moved one part 50 miles down the road, without impairing the quality of your interaction with your friends. That scenario illustrates the goal of the VideoWindow system project: to extend a shared space over considerable distance without impairing the quality of the interactions among users or requiring any special actions to establish a conversation. While the VideoWindow system -a very large screen, full duplex teleconferencing technology that we will describe later in this paper -cannot yet achieve this goal, we believe it can come closer to it than any other system yet invented.

Quilt: a collaborative tool for cooperative writing

Quilt is a computer-based tool for collaborative writing, which provides annotation, messaging, computer conferencing, and notification facilities to support communication and information sharing among the collaborators on a document. In addition, extensible sets of social roles and communication types are used to provide views of a document tailored to individual collaborators or to other users of the document based upon their position in a permission hierarchy. This paper describes the rationale for and design of Quilt.

Task requirements and media choice in collaborative writing

Modalities such as face-to-face meetings permit rich communication, which involves both expressiveness and interactivity. Modalities such as text annotation or electronic mail, however, limit both. Contingency theory, as applied to collaborative writing, says that as the equivocality of the writing task increases, communication modalities that support rich communication are more likely to be used. In addition, it says that if these modalities are used, equivocal tasks can be carried out with greater ease and better results. This article explores these hypotheses using multiple data sources: an interview study tracing the history of 55 published collaborative articles, two field experiments comparing the use of face-to-face communication and electronic mail as media for collaborative writing, and a laboratory experiment comparing voice and text as media for annotating documents. Taken together, the findings of these investigations are loosely consistent with a contingency theory of media use, but they suggest that careful measures of task characteristics are needed to obtain a detailed understanding of the effects of particular task/technology combinations. Further, they indicate that it may be important to consider the distinction between the interactivity and expressiveness components of media richness in making decisions about what technologies to buy or build.

Expressive richness: a comparison of speech and text as media for revision

Both theory and data suggest that that richer, more informal, and more interactive media should be better suited for handling the more complex, equivocal, and emotional aspects of collaborative tasks. To test this hypothesis, we constructed an experiment in which participants were required to make either written or spoken annotations to a document to help a fictional co-author revise it. We seeded relatively error-free texts with errors of different scope . The results provide strong evidence that a richer -in the sense of a more expressive -medium is especially valuable for the more complex, controversial, and social aspects of a collaborative task. Subjects stated that they preferred to use voice to comment on higher-level issues in a document and to use text to deal with lower-level problems of spelling and grammar. When subjects’ annotation modalities were restricted, using written annotations led them to comment on more local problems in the text, while using speech Icd lhem to comment on higher level concerns. When lhey did use written annotations to comment on global problems, they were less successful than when they used spoken annotations. Finally, when they offered spoken annotations, they were more likely to add features, such as personal pronouns and explanation, that made their comments more equivocal and socially communicative. These results indicate the uses to which systems that provide voice annotation are likely to be put. INTRODUCTION Co-authoring documents is common practice in business, industry, and academia. For collaborative writing to succccd, clear communication between cooperating authors is important at all stages of the writing process. One might think of collaborative writing as a variant of the recursive planning, execution, review and revision that is Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specific permission. B 1991 ACM 0.89791.383-3/91/0004/0021 . ..

Iterative design of video communication systems

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UP2P: a peer-to-peer overlay architecture for ubiquitous communications and networking

This paper reviews the design and implementation of several video telephony systems at Bellcore as a case study in iterative design. In contrast to single user compuer applications, communication systems consists of both the interconnection technology and the people who are interconnected. From a user’s point of view, the capabilities provided by the system, the rules for its use, and its reaction to their actions depend jointly on what its developers implemented and how other users behave. This fact has wide-ranging implications for system design, use, and evaluation. In reviewing our design experience, we identify four dilemmas for iterative design that flow from the inherently social nature of communication systems. We conclude with methodological and theoretical suggestions to supplement conventional iterative design principles as applied to communications systems.

Prospects for video telephony

Approaches to building an intelligent consumer-friendly network have evolved over time from centralized switch-based to router- and server-based Internet architectures. We propose to drive this evolution further with a new highly scalable architecture that provides features to users derived from the computational and networking capabilities of very large populations of sophisticated terminals. This architecture relies on emerging peer-to-peer overlay technology. We describe a peer-to-peer overlay design that addresses requirements crucial for consumer applications, including overlay federation, peer heterogeneity, peer mobility, and service discovery. In addition, we introduce the concept of an overlay operator and describe the requirements for managed overlays. We have designed and implemented both a middleware and a peer-topeer platform that illustrates these concepts.

Media spaces and their application in K-12 and college learning communities

Noll overstates the case for the failure of video telephony. This paper reviews research on the use of video in business and at home. Improvements in algorithms, costs, standards and data transport are overcoming technological barriers. Recent field trials show sustained use of video phones and the emergence of novel applications that extend the medium beyond conventional interpersonal communication, including the use of video as data, to access multimedia services and to sustain organizational awareness. In residential settings the dominant use of video telephony is likely to be for routine social calls, for which video is especially suited.

IEEE Standards for Communications and Networking [Guest Editorial]

The CHI community has grappled with the design of media spaces in white collar settings for the past several years [1, 2]. This forum is intended to challenge the assumptions made by that research in light of new settings presented by schools. We explore the opportunities that exist in media space research and design for K-12 and college learning communities.

Debating the media space design space

This is the third Feature Topic in the series on IEEE Standards for Communications and Networking. It follows the July 2008 and January 2009 issues. There are four articles in this issue.