This is an excellent paper tackling one of the most important issues in E-Commerce - agents looking for bargains, and what kind of mechanisms exist for them to evaluate "uncomparable" offerings. In particular, it is clear that as there is an increasing trend towards commoditization, the sellers will try and bundle offerings that make it more difficult for bargain hunting; yet with there mechanisms, agents still have the ability to do just that. This is a good source for the people who want some formalism on this problem that has only been emperically studied.
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