A First Step Towards Understanding Popularity in YouTube

Being popular in YouTube is becoming a fundamental way of promoting one\´s self, services or products. In this paper, we conduct an in depth study of fundamental properties of video popularity in YouTube. We collect and study arguably the largest dataset of YouTube videos, roughly 37 million, accounting for 25% of all YouTube videos. We analyze popularity in a comprehensive fashion by looking at properties and patterns in time and considering various popularity metrics. We further study the relationship of the popularity metrics and we find that four of them are highly correlated (viewcount, #comments, #ratings, #favorites) while the fifth one, the average rating, exhibits very little correlation with the other metrics. We also find a "magic number" in the average behavior of videos: for every 400 times a video is viewed, we have one of each of the following user actions: leaving a comment, rating the video and adding to one\´s favorite set.