How Real People Search – Resnick and Lergier puts forward an interesting concept: pre-click confidence. They have defined this as:

In testing, we measure the Pre-Click Confidence (PCC), which is how sure the user is that the selected link will have the needed information. When the PCC for a link exceeds a match quality threshold, they click. We call this a satisficing constraint because the user is satisfied with the PCC. If the user is in the mood to browse, she can set the PCC threshold low. In this case, she should expect to get lots of false alarms and may not be as frustrated when the link doesn’t have what she is looking for. On the other hand, if she is in a “just the facts” mood (Rozanski et al, 2001), she will set the PCC very high. If she gets fooled by a poorly written description, she will be much more disappointed in the search engine performance.

Here is my summary of the above article’s findings on real people searching:

• Users searching for a specific fact or item have a very high PCC threshold. If none of the search result titles and/or descriptions meet their PCC requirement they will not click on anything.
• Users searching for a general topic compare the perceived PCC value for each result in the set and click on those they have the highest confidence for.
• All searchers want descriptions included with search results.
• Very few people click to see more results beyond the first page returned by their search.

As I think about the search engines and sites that I use, I pretty consistently assign very high PCC values to links posted in weblogs compared to any other source.

www.searchtools.com, who published the article, is an excellent site for researching search technology, btw. I read the reference to this article in their Search Tools News e-mail newsletter.