  Video watching had emerged as one of the most frequent media activities on
the Internet. Yet, little is known about how users watch online video. Using
two distinct YouTube datasets, a set of random YouTube videos crawled from the
Web and a set of videos watched by participants tracked by a Chrome extension,
we examine whether and how indicators of collective preferences and reactions
are associated with view duration of videos. We show that video view duration
is positively associated with the video's view count, the number of likes per
view, and the negative sentiment in the comments. These metrics and reactions
have a significant predictive power over the duration the video is watched by
individuals. Our findings provide a more precise understandings of user
engagement with video content in social media beyond view count.
