"Yet, [old movies] are getting better although not as high as old movies."
1) Don't forget that the raters are self selecting. For very recent movies, the ratings will only be from people who were attracted by hype, and were excited enough to immediately rate a film.
2) All of those ratings will eventually drop as people outside of the target audience(outside of the natural consumers of initial hype) rate the film, reverting the rating to the mean.
3) Most people that are aware of a particular older film are people who remember it because it was/is a favorite, or people who encountered it recently and found it interesting enough to research it on imdb, both probably tending to skew positive.
If you were able to collect the changes in ratings over time, I'd bet that dip of low ratings would always be around the same distance from the present.
I might be off on this, though, because there will always be a qualitative separation between movies that were ratable at the time of release, and movies released pre-imdb.
1. Yes, I agree with you and I wrote on the first post is that that is mostly due to selection bias. http://bugra.github.io/work/notes/2014-02-15/imdb-top-100K-m...
2) That is true but I think that holds for __all__ of the movies not a subset of them.
3) I am not quite sure about that but I think that would be quite interesting look at the temporal information correlation to the rating of the movie.
1) Don't forget that the raters are self selecting. For very recent movies, the ratings will only be from people who were attracted by hype, and were excited enough to immediately rate a film.
2) All of those ratings will eventually drop as people outside of the target audience(outside of the natural consumers of initial hype) rate the film, reverting the rating to the mean.
3) Most people that are aware of a particular older film are people who remember it because it was/is a favorite, or people who encountered it recently and found it interesting enough to research it on imdb, both probably tending to skew positive.
If you were able to collect the changes in ratings over time, I'd bet that dip of low ratings would always be around the same distance from the present.
I might be off on this, though, because there will always be a qualitative separation between movies that were ratable at the time of release, and movies released pre-imdb.