EdgeRank is Dead, Long Live Facebook's EdgeRank Algorithm!
 

Facebook made good on its promise when it announced publically a new way it was going to rank stories in the news feed called "story bumping." With story bumping, Facebook said popular page posts could have a higher chance of being shown even if they are a few hours old (referencing the time decay element) by going to the top of the news feed if the stories were still receiving a lot of likes and comments (referencing affinity score and edge weight elements).