Monday, August 24, 2015

There's also a Wall in Game of Thrones' ratings

A few months back, I looked at the evolution of various metrics (viewership, metacritic ratings, IMDB ratings) for the critically acclaimed TV show Game of Thrones, and also compared overall ratings for the show with Breaking Bad and The Wire which also obtain top ratings from critics and viewers. As I was doing this, I stumbled across the fact that the last Game of Thrones episode (the analysis being done in the middle of the fifth season) had a rating of 10 on IMDB. I had never seen that before. Not a single Breaking Bad or The Wire episode had notched this rating, Breaking Bad did manage to get two 9.8. But after checking back a few days later, the rating of 10 had fell to 9.8, and would continue to fall the next few days.

I had done another post on the evolution of movie ratings and had also noticed that ratings are typically at their highest when the movie comes out and then drop in the following weeks. Does the same phenomenon apply to TV series, albeit on a much shorter time scale?

I pulled IMDB ratings for the final three episodes of the fifth season of Game of Thrones every 15 minutes. There are no spoilers it what follows, unless you consider ratings a spoiler of some kind. While ratings won't tell you what happens (or in Game of Thrones' case, who gets killed!), it might yield insight as to how intense the episode is (or in Game of Thrones' case, how many people get killed!). Consider yourselves warned...

So here's the raw data:

And the total number of voters:

So here's what stands out:

  • all episodes go through a phase when their rating is 10, this occurs in the few hours before the episode airs (horizontal grey lines) and typically based on a few hundred voters only;
  • ratings don't start at 10, that's only the peak value right before air time;
  • rating drops very quickly as the episode airs and right after;
  • value after a few hours is essentially the final stabilized value (maybe another 0.1 drop a few days/weeks later), but much much faster than what we had observed for evolution of movie ratings which typically stabilized after a few months;
  • approximately 80% of voters voted during the first week after the episode was aired;
  • there are bumps in the number of votes when the following episode airs: I'd guess that it's either people who missed the previous episode and do a quick catch-up so they are up-to-date for that evening's new episode, or people who realizing that a new episode is airing that evening and are reminded that they did not vote for the previous week's episode

Now the real question is who are the few hundred people who rated the episode a 10? HBO employees trying to jumpstart the high ratings? Mega fans able to access an early version of the episode? Mega fans already voting without having seen the episode and assuming that all episodes are worth a 10? But then who are the handful of people who voted less then 10 before then?

I myself have not watched the fifth season but VERY intrigued by that eight episode. As of today, the rating is still 9.9, the highest of the entire series, but also higher than any Breaking Bad or The Wire episodes...