How hard would it be to answer questions like "What are the comments that out-score their parents by the widest margins?"?

It's mostly a passing curiosity, so if it's harder to do than "here's roughly the right part of the API and some sample python, go nuts" I probably don't care enough to find out, but I'd love to be able to browse sub-comments that get way more upvotes than their parents, or by a similar token more upvotes than some ancestor comment, or perhaps, more upvotes than the average ancestor comment. Or comments that outscore the original post by the widest margin, possibly normalized by comment depth.

For that matter, does anyone know of a statistical analysis of the effect of comment depth on overall score?

How hard would that be to do? Would it require configuring a database?