Microsoft Office SharePoint Server (MOSS) provides a lot of ways to configure search, but understanding search relevance and how to affect it is not intuitive. There are several factors that affect relevance. In addition, you can configure MOSS to change the relevance. In my research, it appears there are three ways you can affect relevance through configuration / programming (if anyone knows of more, please let me know):
- Authoritative Pages / Demoted Sites – done via the Shared Services Provider search administrative screens. If a page is authoritative or has a smaller click distance or URL depth from an authoritative page it will be more relevant.
- Managed Properties – you can set a weight on a managed property programmatically to affect relevance - or maybe via the Search Relevancy Tool (see below).
- Ranking Class – The RankingParameters property of the Ranking class returns a RankParamCollection object that has a bunch of weighting parameters. This can only be set programmatically – or maybe via the Search Relevancy Tool (see below).
Note that you can also create best bets to show a result that would not otherwise be shown, but I don't consider this part of relevancy.
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