Agents are the catalysts for commerce on the Web today. For example, compar
ison-shopping agents mediate the interactions between buyers and sellers in
order to yield more efficient markets. However, today's shopping agents ar
e price-dominated, unreflective of the nature of seller/buyer differentiati
on or the changing course of differentiation over time. This paper aims to
tackle this dilemma and advances shopping agents into a stage where both ki
nds of differentiation are taken into account for enhanced understanding of
the realities. We call them next-generation shopping agents. These agents
can leverage the interactive power of the Web for more accurate understandi
ng of buyer's preferences. This paper then presents an architecture of the
next-generation shopping agents. This architecture is composed of a Product
/Merchant Information Collector, a Buyer Behavior Extractor, a User Profile
Manager and an Online Learning Personalized-Ranking Module. We have implem
ented a system following the core of the architecture and collected prelimi
nary evaluation results. The results show this system is quite promising in
overcoming the reality challenges of comparison shopping. (C) 2000 Elsevie
r Science Ltd. All rights reserved.