The popularity and the authority of a website have both played a part in determining how high a site will rank in the search results for a specific query. But is one better than the other at determining the quality of information returned on a specific search?

That is a question that Matt Cutts, head of Google’s Webspam, addressed in a recent ‘Webmaster Help’ video.

It helps to understand the difference between popularity and authority.  In general, popularity is tied to traffic statistics.  Sites that generate a great deal of traffic tend to be thought of as popular;  much in the same way as people who have many friends and are always surrounded by people are considered to be popular.  Popularity also takes in to account the time visitors spend on a website.  Some search engines also include links as well as clicks in the mix.

Conversely, authority is more about substance and relevant topic-specific content.  You cannot claim to be an authority; others give you that status by linking to you, and citing your vast content as important and up to date.  Site longevity is also a deciding factor.

Cutts said that when determine a good authoritative match Google looks at the links to a site and what percent actually talk about the query.  Let’s say you search on Denver search engine optimization.  How many firms in this category have links that actually talk about search engine optimization?  If there are a lot of links or a large fraction do, then that site is deemed fairly topical and may be an authority for the phrase Denver search engine optimization.

Cutts alluded to some algorithmic changes to help determine if a site is a better match for a search query.  For example, if you have a medical query, Cutts said they are trying to avoid simply saying, “Hey, this is a well-known site, therefore it should match for this query.”  And get to “This is a site that actually has some evidence that it should rank for something related to medical queries.”  He feels that this is an area where they can improve the algorithms even more.  No date or other information was indicated.