RIP Google PageRank score
RIP Google PageRank score: A retrospective on how it ruined the web
Originally, Google’s PageRank was a tool to determine the “importance” of a given page, derived from the number of pages linking to it. However, once Google made this information public in 2000, the economy of buying and selling links in order to increase PageRank emerged. This marketplace quickly grew out of control until Google was forced to take action and begin penalizing pages that were being linked from these large link sellers. In 2005, Google took further action with the introduction of the nofollow tag, allowing publishers to prevent certain links from contributing to their PageRank. After 2005, Google began updating its public PageRank scores less and less until finally in 2010, Google took down and the public directory of PageRank altogether. After this event, the economy for buying and selling links to increase PageRank began to decrease as there was no way of knowing if those extra links were really helping your rank or not.
This article connects to the PageRank discussion held in class. PageRank heavily resembles the hub and authority models discussed in class and can be updated through the hub and authority update rules. Specifically, we can model PageRank updates by finding eigenvalues of a given scaled update matrix.