Link Popularity
http://www.highrankings.com/linkpopularity.htm

Whalen, Jill
High Rankings Advisor
2004

Abstract:

For years, 'link popularity' and 'Google PageRank' have been the talk of the town in the search engine optimization community. However, the definition of link popularity and how it differs from PageRank (PR), as well as how much effect these actually have on search engine rankings, is often misunderstood.