Comment Re:Mis-title (Score 5, Informative) 367
PageRank doesn't actually distinguish between "portals" and "authorities." It "only" does a link-analysis of the web by essentially mutiplying some ranking vector by a matrix representing the links in the web, with a random jump to another location taking place with a certain probability to create a new ranking vector. Once this converges, you have the new "PageRank."
PageRank scores are calculated completely independently of the search query. You are probably thinking of Kleinbergs HITS (or Hubs and Authorities) algorithm which uses an initial search query to prune the search space, and then identifies hubs and authorities in the web. In contrast to PageRank, which only uses forward links to calculate its rankings, HITS uses both forward and "backward" links to figure out its ratings. Furthermore, unlike PageRank, HITS produces different scores for different queries.
The above tells us the following: That Kuro5hin and Slashdot have high pageranks not because of their excessive numbers of outlinks, but because many people point to their frontpages. Similarly, these high PageRanks mean that people that Slashdot or Kuro5hin point to get higher scores as well.
PageRank scores are calculated completely independently of the search query. You are probably thinking of Kleinbergs HITS (or Hubs and Authorities) algorithm which uses an initial search query to prune the search space, and then identifies hubs and authorities in the web. In contrast to PageRank, which only uses forward links to calculate its rankings, HITS uses both forward and "backward" links to figure out its ratings. Furthermore, unlike PageRank, HITS produces different scores for different queries.
The above tells us the following: That Kuro5hin and Slashdot have high pageranks not because of their excessive numbers of outlinks, but because many people point to their frontpages. Similarly, these high PageRanks mean that people that Slashdot or Kuro5hin point to get higher scores as well.
