Granted, it's been a year or two since I ditched Netflix, but as I recall their recommendation system already ranked the importance of ratings based on how similar the other reviewer's tastes were to yours (I imagine by finding other people who tended to have ranked movies the same as you).
My impression was that they were far more concerned with doing well with recommendations than with the plain rankings.
That's true, but their entire model is still built on a database built up of 5-discrete-value ratings. True, it does seem that they place an emphasis on reviewers' similar tastes, but they are still crippled by the poor resolution of their data.
They're spending so much energy tweaking their 5-star algorithm by tiny amounts, but it seems like they'd be much better off investing in a richer database medium - like attention spent browsing various genres on their website while looking for their next movie...
I don't know, it just seems like the five star system is so crude for a company willing to spend millions to improve their recommendation system by even a tiny amount.
"So you like this movie? Like, would you say, "4 stars" like it, or "5 stars" like it?" really? That's what your database is made of? - know what i mean?
That is a great point.. imagine a prof issuing grades that way. I'd love to see someone with a 100-point system do some A/B testing to see how much recommendations degrade with a 5-point system.
My impression was that they were far more concerned with doing well with recommendations than with the plain rankings.