Papers in PDF format

system avoids spamming since the question or answer dialog only involves two people. At any point, any user
may complain to the administrator and if a user is clearly abusing the system, they can lose their account
privileges. This is thin protection against a determined prankster, but the cascading effect in newsgroups or
other similar systems is avoided. Once again, the emphasis is on simple and workable solutions in contrast to
what would be required to build a bullet-proof system.
Test Results
The Help-Exchange system has been through two levels of testing so far. After an initial demonstration at the
1995 TCAD Symposium [Losleben & Boning 95], a two week alpha test was performed in late Aug. 1995 with
a group of approximately 15 volunteers. The alpha test uncovered a number of design flaws and suggestions
for improvements. In addition to the bugs one expects to uncover in testing with real users, a number of useful
suggestions were made by the alpha testers. The taxonomy design was completely reworked to allow selective
navigation of large taxonomies. Question redirection by an expert was added, as was the Unsolved Mysteries,
Follow-up Questions, better navigation aids and the Archive. The most serious bugs had to do with the unique
constraints that the web interface imposes on the system design. In particular, web browsers retain state in the
form of previously visited pages. Since we rely on the data base at the server side, it is easy for stale pages at
the client side to be in conflict with the state of the data base. Unless carefully designed, this produces an
awkward or even corrupted interface with the database.
Subsequent to these changes, a longer beta test was undertaken in the Fall and Winter quarters with a larger
group of about 30 users at Stanford and MIT. This was the first attempt to satisfy a real need for assistance
between users. Overall the beta test ran smoothly and a few improvements were incorporated to make the
interface more intuitive and to eliminate aspects of the interface which were error-prone for inexperienced
users. More error testing and handling was added and an administrator interface was added to assist in that
function. A surprising result of the beta test was the number of new options which were suggested. Many of
the users of the system wanted more flexibility in use of the economic model. For example, some would be
willing to "pay" more for faster service or to send a question to more than one expert. These suggestions are
being considered in balance with our desire to build a simple system.
At this time, a second beta test is planned to begin in Apr. 1996 and is expected to involve about 400 users.
Subsequent to that, the system will be made available to a much larger research and education community.
Future Direction
Two major enhancements to the system are being considered. First, in consideration of quality issues, we plan
to add a special class of user who is copied on all correspondence within a category of the taxonomy. This is
specifically to address a potential application to customer support systems where an individual is assigned the
responsibility for monitoring correspondence and correcting problems. This brings the Help-Exchange
application closer to systems that support user groups, yet still keeps the volume of traffic down to a minimum
for most users.
The most challenging future direction involves the conversion of the system from a centralized system
(presently implemented at Stanford) to a distributed system for which independent taxonomies might be
developed at other sites, possibly reflecting the unique areas of expertise at those sites. The objective would be
to allow a user seeking information to follow a hyperlink to another taxonomy at another site.
This presents two problems, one fairly simple, the other distressingly difficult. First, there would have to be
some mechanism for exchange of barter value between sites. There is similar work that is well developed for
real monetary systems that the implementation of this is not expected to be difficult. The harder problem is
found in accommodating what would certainly be dissimilar taxonomies. One could not expect to enforce a
common ordering discipline for taxonomies across a wide range of knowledge domains, or even common
ordering disciplines for the same domain developed independently at different sites. For the World Wide Web,
an absence of organization is expected, but the implication of a taxonomic organization where that is not likely
to happen between sites might be quite confusing. The research for the summer of 1996 is focused on this
problem.