Edgerank is facebook algorithm then decide which story going to appear in your news feed. There hide all the uninteresting and boring stories, it shows all interested content or related content to your interest.
Nowadays, news running over Internet that Facebook  is tweaking with this algorithm that hurt the advertisement industry over Facebook. And it’s a part of my dissertation that I’m working on social computing it some interesting stuff for me as well so I’m writing this article that how edge rank is working. What I written here is just abstract, because actual algorithm hidden from all.
But its better idea to have knowledge about making article, post, like in such manner that increased my edgerank. There is no direct trick to improve that.
Let’s see how edge rank is working
Edge rank is algorithm runs on 3 factors.
Ue: affinities score between the nodes
We: weight for each edge type (create, like, comment etc)
De: time decay , how long edge was created
Affinity Score (Ue)
Affinity score is a numerical relationship with other. For example I’m frequently posting to my friend`s wall then the affinity score will get very high. But any person is in my friendliest but there is no any social relation between him and me, like comment, tag, like or share then this post will not been displayed to my news feed. For each and every node this algorithm will create affinity score. Affinity score also calculate your accent as well that if you’re clicking someone’s link, sharing the post, tagging him to your picture, liking etc we create your edge rank. Again edge rank is a one-way for example I’m writing something to my friends wall but is not taking any activity to my wall then my page rank toward him is a higher, but he’s rank toward me might be low. Cricket
Edge Weight (We)
Each category of edge has the weightage. Like has a low weightage than the commenting. It means that if you are writing your status will have weightage less than you uploading the picture. Every component has its own weightage.
Time Decay (De)
Time decay is rolling over time, as the story gets older it loses its rank. That known as “old news”. So that if you post anything at a perfect time will gain more score.
There is no direct way to improve your rank but here is some suggestion that might help you to improve your page rank. For further reading citations are given below.
How to improve your edgerank of Facebook 
Add photos to each post.
Post at the right time of day.
Ask for interaction. (like “If you like then share…”,”Gujarati ho to like karo”…)
Think outside the work week.
When in doubt, post a graphic.
 “6 Ways to Improve Your Facebook EdgeRank” http://www.business2community.com/facebook/6-ways-to-improve-your-facebook-edgerank-0285788,2010