Co-Chairs:
Dr. Jock D. Mackinlay and Dr. Polle T. Zellweger
Xerox PARC
3333 Coyote Hill Rd.
Palo Alto, CA 94304
{mackinlay, zellweger}@parc.xerox.com
Panelists:
Professor Mark Chignell, University of Toronto
Dr. George Furnas, Bellcore
Professor Gerard Salton, Cornell University
Much has been written about the potential benefits of information
technology for transforming business, science, medicine, engineering, and
education. However, this potential will not be realized if users cannot
access online information easily and efficiently. Two common user
interface approaches for information access are browsing and search.
Broadly speaking, Browsing involves navigation through an information
collection, and search involves specification of queries to retrieve
information from a database [4]. Neither approach appears
to be entirely adequate for accessing the information becoming available on
the Internet.
For example, consider accessing the World-Wide Web [1], a
very
large network-based hypertext system, with Mosaic, a popular
browsing-oriented user interface to the Web. One problem with browsing the
Web is that there are so many places to explore that the user may never
find the desired information. On the other hand, web-crawler databases
provide searchable indexes of Web documents. However, formulating queries
to retrieve the desired information from such databases can be quite
difficult. Most researchers believe these two approaches complement each
other. The open question is how to combine them synergistically.
This panel brings together a diverse collection of researchers who are
familiar with these two user interface approaches for information access.
The panelists represent a variety of communities, including hypertext,
information retrieval, psychology, cognitive science, and visualization.
Each panelist will give a short, informative presentation describing how
they believe browsing and search can be combined synergistically. The
panelists and the audience will then discuss and compare the different
views, working toward a combined approach that addresses all of the issues.
I will review a variety of navigation and structuring paradigms that have
been used in the hypertext community, from pure unstructured browsing along
author-created links, to the use of query-based information retrieval
techniques to create virtual links to items of current interest. The Mosaic
interface to the World-Wide Web uses both techniques in permitting users to
navigate the web. Browsing raises traditional problems of disorientation
and cognitive overhead [2], but has value in information
serendipity. Additional structuring techniques such as maps and paths can
make browsing more effective while retaining some of the unfolding nature of
the browsing paradigm.
Polle Zellweger received a Ph.D. in computer science from UC Berkeley in
1984. She has been a researcher at Xerox
PARC since 1981. As manager of the Active Documents group at PARC, she has led
research into architectures, uses, and user interfaces for documents with
dynamic content. Her particular focus has been structures for hypermedia
documents, including path mechanisms and synchronization of multiple media.
In the foreseeable future, large masses of machine-readable text will
be made available to a wide variety of potential users. Methods must
then be available to help users find their way through the collections
in flexible ways.
Procedures are described for automatically analyzing the structure of
full-text collections, and for using structural characteristics to
identify text themes and design browsing and selective text traversal
strategies.
Gerard Salton has been a professor of computer science at Cornell
University for nearly 30 years. He has designed advanced text analysis and
retrieval tools, such as the Smart system, and has written extensively
about text-based search and retrieval. His most recent book is ``Automatic
Text Processing'', Addison Wesley, 1989.
Designers of information exploration systems appear to be stuck on the
horns of a dilemma. Information retrieval is difficult and requires
considerable skill (including knowledge of indexing policy), while browsing
requires considerable authoring effort in building the link structure. I
will propose the use of user-centered designs that provide tools that allow
users to mix and match browsing and retrieval. The presentation will be
based on research that we have carried out on graphical querying in the
past few years. In this approach, the user forms queries by marking up
text. This approach simplifies the task of building Boolean queries. In
addition, other tools can help the user find interesting terms for
exploration. One of the features of this approach is that techniques such
as visualization can be added to it as they become available. The idea is
to surround users with powerful tools and a customizable user interface and
then let them construct the information exploration environment that suits
them best.
I will briefly illustrate the use of this approach with the ST-PatTREC
system that we have developed. I will show how this approach was used to
search for information in a 300 megabyte subset of the TIPSTER database.
Advantages and disadvantages of the user-centered approach will be
discussed.
Mark Chignell is an associate professor of Industrial Engineering at the
University of Toronto. He has a Ph.D in Psychology and an MS in Industrial
and Systems Engineering. He has research interests in the areas of user
interface design and information technology. His current research focus is
on multimedia information systems and electronic books.
Navigation and querying are the contrasting interaction components
underlying what in this panel are called "browsing" and "search". They
differ regarding, for example, semantic representation, vocabulary
problems, structuring costs, and meta-knowledge requirements. Many
synergistic designs are possible, including:
Examples of these and other approaches will be sketched. An important
question is whether the benefit will outweigh the combined cost (e.g., from
having to build both a search engine and a navigation structure).
George Furnas is currently Director of Computer Graphics and
Interactive Media research in the Computer Science department at Bell
Communications Research. He has worked for almost 15 years in
human-computer interaction, specializing in areas related to
information access and visualization, and was the keynote speaker at
the 1993 IEEE visual languages conference. His specific contributions
include work on statistical semantics, adaptive indexing, latent
semantic indexing, generalized fisheye views, graphical deduction
systems, high dimensional visualization, and multitrees.
Visualization does not easily extend to large, remote databases, such as
the ones envisioned for the national information infrastructure, because
slow access limits high-bandwidth interaction. I will describe a set of
user interface techniques for creating Organic User Interfaces for
Information Access, which help users manage their information retrieval
searches [3]. Organic User Interfaces combine search and
browsing through link-generating queries that are automatically explored by
semi-autonomous agents. Visualization techniques are used to provide the
user with intuitive control of these agents to direct the search toward
desirable information without wasting resources. Metaphorically, the user
becomes a gardener who trims and fertilizes an information landscape that
is being grown by embedded search processes.
Jock D. Mackinlay joined Xerox PARC after receiving a Ph.D. in 1986 from
Stanford University on the automatic design of graphical presentations of
relational information. For the last five years, he has been collaborating
with Stuart Card and George Robertson on the Information Visualizer (IV),
an information visualization application based on 3D graphics and
interactive animation.
Abstract
This panel seeks a synergy between two common user interface approaches for
information access: browsing and search. Panelists from a variety of
backgrounds including information retrieval and hypertext will give short
presentations suggesting what the synergy might be from their individual
perspectives. The panelists and the audience will then jointly discuss how
to achieve an overall synergy.
Keywords:
information access, browsing, search, querying,
navigation, information visualization
Introduction
PANELIST STATEMENTS
Polle T. Zellweger: Hypertext navigation paradigms
Gerard Salton: Text structure analysis
Mark Chignell: User-centered information systems
George W. Furnas: Navigation-by-query, query-by-navigation, and other tricks to try
Jock Mackinlay: Embedding queries in visualizations
Mon Feb 6 16:44:48 PST 1995