Articles are sorted by "Active Date" some sites like to have content pages within departments displayed in a particular order.
To sort you articles follow this tutorial.
Sort article by Page rank
The page rank ONLY breaks a tie, when 2 or more articles have the same active date.
To sort articles by pages rank you will want to make sure the articles all have the same active date and page rank number in their order
If you use the same active date you would change the page rank so the first article is:
Page rank 01 - will appear at the top
Page rank 02
Page rank 03
and so on
Sort article by Active date
Set the page rank on all articles to 50 so the active date will override the page rank.
For articles to be ranked by active date.
Article #1 - Set the active date to October 31st - Page rank 50
Article #2 - Set the active date to October 29th - Page rank 50
Article #2 - Set the active date to October 28th - Page rank 50
and so on
October was used as an example, you can use any month, but for the articles to appear at the top MUST be the most recent data.
If you wanted a page to constantly appear at the top of your article list, you would set the date well into the future and keep the page rank at 50.