I say that this result is no surprise because, as I noted just a couple of entries ago, that's the power of brands. In most instances consumer's view branded products as preferable to their non-branded competitors, even when there is little or no actual product difference. Anyway, Greg has a good write up of the overall study, so if you're interested you should go check it out. With that, I should note that there was another interesting tid-bit in the study that is worth mentioning:
The authors used a base-line level of relevance as the measuring stick to gauge the power of the individual search engine brands. In other words, outside the context of the study, the authors (or someone - they don't give details on this) looked at the results from each engine and scored their relevancy. It is the deviation from this baseline "score" that provides the basis of the brand study.
The process was done for the following four static queries: (i) camping mexico (travel query); (ii) laser removal (medical query), (iii) techno music (entertainment query); and (iv) manufactured home (ecommerce query).
The overall average baseline relevancy of results for all of the engines studied was 36%. In other words, on average 36% of the results served up by each engine was relevant to the query. While these results slightly differed from individual engine to engine and from individual query to query, for the most part the baseline relevancy scored for each engine/ query hovered right around that 36% number. With one exception.
The only big deviation from the 36% relevancy average was Google's score for the results returned on the query "manufactured home" - where they were judged to be 69% relevant. (In fact, oddly enough, for each of the other three queries, the base-line showed Google being outperformed for relevancy by each of Yahoo and MSN).
So the only the only stand-out performance in terms of relevancy in this study is Google's ability to serve up more relevant results in the most monetizeable of all the queries. Coincidence? Probably not. In the now famous words of Larry and Sergey, "we expect that advertising funded search engines will be inherently biased towards the advertisers and away from the needs of the consumers."