How I determine who I link to:
I link to a webpage that isnot a links page from a webpage of mine that isnot a links page. The page I link to must be #1 in G search engine for its search phrase as it is linking back to my webpage which is #1 for a search phrase competing with 1 to 5 million search results. That is how I determine authority by closing my links with authority and it helps ALOT. I get 50+ link requests per day and I may establish a new link once in a 3-4 week period. I donot go looking for links. I donot want to sound cocky but the smart link partners can see and realize the potential of linking with me, but there are alot of smart people who try to screw me too. I can look at there webpage and tell what their best resault they are being found for in Google search and I can tell through this and link structure and a few other things whether they are worth linking too.
Just my opinion