Facebook, Buzz, Reader, and other social networking sites all have one thing in common: if you like something then you get to like it. But you never get to dislike what you dislike. (Sure you can unlike what you previously liked, but just as with that other interest rate you are constrained by the zero lower bound. You can’t go negative.)
This kind of system seems to pander to people such as me who obsessively count likes (and twitter followers, and google reader subscribers and…) because for people like us even a single dislike would be devastating. With only positive feedback possible we are spared the bad news.
It is entertaining to see him uncover some economics of the *like* button. Basically, because we are busy and it takes time to hit the like button and to comment, hitting *like* actually means something. Those who hit *like* are actually saying that they *really like* the status or post.
Controversial/offensive YouTube videos frequently get a mix of likes and dislikes. Both of those videos that I linked had over 100 dislikes (but also over 1000 likes) and you can see why some people would like or dislike those videos. They're provocative, and before you know it, you've watched the whole thing. Whether you liked it or not, you are prone to rate it after you watched the whole video.
My YouTube video tutorials tell a different story -- they rarely generate dislikes. At the time of this post, my most *liked* video has 74 likes (and no dislikes). My most *disliked* video has 2 dislikes, but it has 40 likes.* From the comments on that video, I can identify the two dislikes. One was for too much math, and one for the camera being shaky (and me skipping some algebra). I fixed the shakiness issue with a tripod.
Why does my channel get so few dislikes? If you dislike my videos, you're not going to watch the whole thing. You may watch a minute of it before you leave to something else, but you will be (at most) mildly offended by my video when you leave. Given that it takes some mental energy (and time) to dislike, the fact that most people who don't like my videos are only mildly offended means that my videos get few formal dislikes.
In other words, if someone dislikes my video, they must *really* dislike it. This is Ely's it-costs-to-like argument, but applied to dislikes. Hence, if a video on YouTube has 40 likes and 2 dislikes, all we can infer is that 40 people *really liked* it and 2 people *really disliked* it. But, there's no way to infer the true fraction of people who like or dislike the video (because there are people who have an opinion, but didn't bother to register it).
Then again, these omitted ratings close to indifferent anyway. If they chose not to vote, they must not want me to know how they feel. Selective ignorance is bliss.
*I think this is my most disliked video. I haven't found a good way to get YouTube to compare the dislikes and likes across videos.