I was wondering about the effects of external links and depth of the file linked to. For example would it be better for ranking to be linking to:

mydomain.com/

or

mydomain.com/dir/dir/file.php

The think is I am doing the latter, because there is a specific file I want to link to that is several dirs deep, but google ranking doesn't seem to recognize anyone linking to my site. There are at least 20 that do, however. Mind you I don't sell or have ads. I just was wondering. I noticed my rank was 0 the other day and many smaller sites that I have made for others are ranked 4-7. I don't really understand this stuff.