Performing a search on the World Wide Web (WWW) and traversing the
resulting links is an adventure in which one encounters both credible
and incredible web pages. Search engines, such as Google, rely on
macroscopic Web topology patterns and even highly ranked 'authoritative'
web sites may be a mixture of informed and uninformed opinions. Without
credibility heuristics to guide the user in a maze of facts, assertions,
and inferences, the Web remains an ineffective knowledge delivery
platform. This report presents the design and implementation of a
modular extension to the popular Google search engine, MEDQUAL, which
provisions both URL and content-based heuristic credibility rules to
reorder raw Google rankings in the medical domain. MEDQUAL, a software
system written in Java, starts with a bootstrap configuration file which
loads in basic heuristics in XML format. It then provides a subscription
mechanism so users can join birds of feather specialty groups, for
example Pediatrics, in order to load specialized heuristics as well. The
platform features a coordination mechanism whereby information seekers
can effectively become secondary authors, contributing by consensus vote
additional credibility heuristics. MEDQUAL uses standard XML namespace
conventions to divide opinion groups so that competing groups can be
supported simultaneously. The net effect is a merger of basic and
supplied heuristics so that the system continues to adapt and improve
itself over time to changing web content, changing opinions, and new
opinion groups. The key goal of leveraging the intelligence of a
large-scale and diffuse WWW user community is met and we conclude by
discussing our plans to develop MEDQUAL further and evaluate it