The 10:1 ratio of video overall value.

[videoeditgr]

Not really based on an analysis or scientifically researched.
It is just an observation while browsing youtube videos.
"Ok" videos seem to have 1 dislike over every 10 likes.
" not so ok" videos get more than 1 dislikes every 10 likes.
"Kind of better" videos get more than 10 likes on every dislike.

Really subjective rule of thumb, while viewing videos
I check the like/dislike analogy which usually fits
what described above.

 

[Andrewcu]

It also depends on how many loyal subscribers the channel has (because some fans like videos from certain creators without watching them first) and whether the creator asked for likes. But generally that rule works pretty well excluding videos for young kids/toddlers, where the like and dislike buttons are often hit randomly.