> trained to maximize viewing time (and thus ads you see), instead of showing you videos you'd actually enjoy more. How would youtube quantize how much enjoyme

> trained to maximize viewing time (and thus ads you see), instead of showing you videos you'd actually enjoy more. How would youtube quantize how much enjoyment you're having, if not by tracking viewing time? As an aside, when watching youtube on my TV, I don't think there's a way to thumbs up or down videos. Even on my PC, when the video is in fullscreen, there's no way to thumbs up or down either.