Frank M. Shipman

Spatial hypertext: designing for change

Introduction Hypertext1, in its most general sense, allows content to appear in different contexts. The immediate setting in which readers encounter a specific segment of material then changes from reading to reading or from reader to reader. Authors collect and structure materials to reflect their own understanding or in anticipation of readers’ possible interests, needs, or ability to comprehend the substrate of interrelated content.

VIKI: spatial hypertext supporting emergent structure

The emergent nature of structure is a crucial, but often ignored, constraint on authoring hypertexts. VIKI is a spatial hypertext system that supports the emergent qualities of structure and the abstractions that guide its creation. We have found that a visual/spatial metaphor for hypertext allows people to express the nuances of structure, especialy ambiguous, partial, or emerging structure, more easily. VIKI supports interpretation of a collected body of materials, a task that becomes increasingly important with the availability of on-line information sources. The tools data model includes semi-structured objects, collections that provide the basis for spatial navigation, and object composites, all of which may evolve into types. A spatial parser supports this evolution and enhances user interaction with changing, visually apparent organizations.

Spatial hypertext and the practice of information triage

Information triage is the process of sorting through relevant materials, and organizing them to meet the needs of the task at hand. It is a practice that has become increasingly common with the advent of “at your fingertips” information resources. To explore the characteristics of information triage and its interaction with spatial hypertext, a medium we claim supports the process, we have studied subjects engaged in a time-constrained decision-making task using a large set of relevant documents. We use the study task to investigate information triage under three different conditions: one in which the participants used paper documents, and two others in which the participants used variants of VIKI, a spatial hypertext system. Our findings suggest that during information triage attentional resources are devoted to evaluating materials and organizing them, so they can be read and reread as they return to mind. Accordingly, hypertext tools to support the practice should facilitate the rapid assimilation and assessment of new material, aid in the creation and management of a fluid category structure, allow readers to track their own progress through the information, and use minimum-effort methods to promote the intelligibility of results.

Hypertext paths and the World-Wide Web: experiences with Walden's Paths

Walden’s Paths applies the concept of hypertextual paths to the World-Wide Web. Walden’s Paths is being developed for use in the K–12 school environment. The heterogeneity of the Web coupled with the desirability of supporting the teacher-student relationship make this an interesting and challenging project. We describe the Walden’s Paths implementation, discuss the elements that affected its design and architecture, and report on our experiences with the system in use.

Supporting knowledge-base evolution with incremental formalization

A number of systems have been built which integrate the knowledge representations of hypermedia and knowledge-based systems. Experiences with such have shown users are willing to use the semi-formal mechanisms of such systems systems leaving much structure implicit rather than use the formal mechanisms provided. The problem remains that it is hard (1) to encode knowledge in the formal languages required by knowledge-based systems and (2) to provide support with the semi-formal knowledge found in hypermedia systems. Incremental formalization enables users to enter information into the system in an informal or semi-formal representation and to have computer support for the formalization of this information. The domain independent Hyper-Object Substrate (HOS) differs from other systems that integrate hypermedia and knowledge-based system styles of representations in that it enables the incremental addition of formalism to any piece of information in the system. HOS actively supports incremental formalization with a set of tools which suggest new formalizations to be added to the information space. These suggestions are based on patterns in the informally and semi-formally represented information and the existing formalized knowledge in the information space. An important assumption is that suggestions need not be completely accurate to be of general benefit to users. These suggestions provide a starting point which can be edited, thus changing part of of formalization from creation to modification. XNetwork, an environment the process supporting the design of computer networks, is one of several applications that have been created with HOS. Experiences with HOS show that its flexibility for incrementally adding and formalizing information is useful for the rapid prototyping and modification of semi-formal information spaces.

Seeding, evolutionary growth and reseeding: supporting the incremental development of design environments

We describe an approach to acquiring information during the creation and use of domain-oriented design environments. Our model consists of three phases: seeding, evolutionary growth, and reseeding. A seed for a domainoriented design environment is created through a participatory design process between environment developers and domain designers by incorporating domain-specific knowledge into a domain-independent architecture for design environments. Evolutionary growth takes place as domain designers use the seeded environment to undertake specific projects. Reseeding is a process that reinvolves the environment developers to help domain designers better organize, formalize, and generalize knowledge added during the use phases,

Supporting indirect collaborative design with integrated knowledge-based design environments

We are developing a conceptual framework and a demonstration system for collaboration among members of design teams when direct communication among these members is impossible or impractical. Our research focuses on the long-term, indirect communication needs of project teams rather than the short-term needs of face-to-face communication or electronic mail. We address these needs with integrated, domain-oriented design environments. Our conceptual framework and our system-building efforts address two major issues: (a) How does individual work blend into project work (especially in large projects that span great distances and time)? and (b) What role do the work objects play in this coordination? We use a specific domain-oriented design environment (NETWORK-HYDRA-for the design of computer networks) to illustrate our approach, and we discuss HYDRA as the underlying domain-independent, multifaceted architecture for design environments.

Integrating different perspectives on design rationale: Supporting the emergence of design rationale from design communication

Design rationale is a topic that implies different things to different people. To some it implies argumentation and frameworks for argumentation. To others it implies the documentation of design, like that required for many types of industrial or government work. Still others describe design rationale as the capture and potential reuse of normal communication about design. These perspectives of design rationale use different representations, which influence their ability to capture and to retrieve and use information. We propose an integrated approach to design rationale where design communication is captured and, over time, incrementally structured into argumentation and other formalisms to enable improved retrieval and use of this information. Two systems, PHIDIAS and the Hyper-Object Substrate, are used to demonstrate: (1) how to capture and integrate a variety of design information, (2) how to support the structuring of unstructured information, and (3) how to use design information to actively support design.

Which semantic web

Through scenarios in the popular press and technical papers in the research literature, the promise of the Semantic Web has raised a number of different expectations. These expectations can be traced to three different perspectives on the Semantic Web. The Semantic Web is portrayed as: (1) a universal library, to be readily accessed and used by humans in a variety of information use contexts; (2) the backdrop for the work of computational agents completing sophisticated activities on behalf of their human counterparts; and (3) a method for federating particular knowledge bases and databases to perform anticipated tasks for humans and their agents. Each of these perspectives has both theoretical and pragmatic entailments, and a wealth of past experiences to guide and temper our expectations. In this paper, we examine all three perspectives from rhetorical, theoretical, and pragmatic viewpoints with an eye toward possible outcomes as Semantic Web efforts move forward.

Searching for the missing link: discovering implicit structure in spatial hypertext

Hypertexts may be implicitly structured, based on either node content or context. In this paper, we examine implicit structures that rely on the interpretation of node’s spatial context. Hypertext authors and readers can perceive and understand these idiosyncratic structures, but, because they are implicit, they cannot be used by the system to support users’ activities. We have explored spatially structured hypertext authored in three different systems, and have developed heuristic recognition algorithms based on the results of our analyses of the kinds of structures that people build. Our results indicate that (1) recognition of implicit structures in spatial hypertext is feasible, (2) interaction will be important in guiding such recognition, and (3) the hypertext system can provide layout facilities that will render later systematic interpretation much easier. Found structures can be used as a basis for supporting information management, as a straightforward way of promoting knowledge-base evolution, as a way of solving representational problems endemic to many hypertext systems, or as a basis for collaboration or interaction.