8 Appendix A: Advertising and Mixed Motives<p>Currently, the predominant business model for commercial search engines is advertising. The goals of
the advertising business model do not always correspond to providing quality search to users. For
example, in our prototype search engine one of the top results for cellular phone is "The Effect of
Cellular Phone Use Upon Driver Attention", a study which explains in great detail the distractions and
risk associated with conversing on a cell phone while driving. This search result came up first because
of its high importance as judged by the PageRank algorithm, an approximation of citation importance on
the web [Page, 98]. It is clear that a search engine which was taking money for showing cellular phone
ads would have difficulty justifying the page that our system returned to its paying advertisers. For this
type of reason and historical experience with other media [Bagdikian 83], we expect that advertising
funded search engines will be inherently biased towards the advertisers and away from the needs of the
consumers.
Since it is very difficult even for experts to evaluate search engines, search engine bias is particularly
insidious. A good example was OpenText, which was reported to be selling companies the right to be
listed at the top of the search results for particular queries [Marchiori 97]. This type of bias is much
more insidious than advertising, because it is not clear who "deserves" to be there, and who is willing to
pay money to be listed. This business model resulted in an uproar, and OpenText has ceased to be a
viable search engine. But less blatant bias are likely to be tolerated by the market. For example, a search
engine could add a small factor to search results from "friendly" companies, and subtract a factor from
results from competitors. This type of bias is very difficult to detect but could still have a significant
effect on the market. Furthermore, advertising income often provides an incentive to provide poor