AlyssaS - 12:57 pm on Apr 22, 2011 (gmt 0)
What if the same type of idea is now applied negatively. The more internal anchor text links to bad pages, the more likely, Google estimates, users will have a bad experience on that site.
Or it could be a ratio of internal links to external links. If a page only has internal links, it means no-one outside thinks it is worth linking to (and links from scrapers don't count as they link indiscriminately).
A good test of the above could be finding out whether pointing fresh external links to a page revives it.