As far as I can understand based on fragmented conversations from ~2 years ago + Mbin's codebase, Mbin reputation is the sum of:
(boosts * 2) + upvotes (i.e., favorites) - downvotes (if enabled on the instance)
For Fedia specifically, it's possible that the history might look a bit weird for older users because of some database purges / cleanups that have happened in the past. A lot of comments that were 1.5 (?) years or older are no longer visible, but it's possible that they're still counting towards reputation - unsure! It might also be the case that (more recent) deleted posts still contribute towards reputation changes?
edit: singling your own profile out (hopefully you don't mind), and we get the attached image (here for lemmy users), where we can count from the bottom up as:
- +0
- +1
- +1
- +0
- +20 (thread)
- +0
- +1
- +6
- +5 (this thread!) === 34, the same as what we see (as of this edit) as your reputation score
Which does show the linearity of upvotes/favorites. I briefly checked boosting this thread to see the effect on your rep and it went up by 2 (..which took a while to re-process when I undid it), so that +2 seems to check out. I also checked downvoting and that similarly changed it by -1 so I guess that's accurate ¯\_(ツ)_/¯
