by   Ranker
in Data Science, interest graph, Opinion Graph

The Opinion Graph predicts more than the Interest Graph

At Ranker, we keep track of talk about the “interest graph” as we have our own parallel graph of relationships between objects in our system, that we call an “opinion graph”.  I was recently sent this video concerning the power of the interest graph to drive personalization.

The points made in the video are very good, about how the interest graph is more predictive than the social graph, as far as personalization goes.  I love my friends, but the kinds of things they read and the kinds of things I read are very different and while there is often overlap, there is also a lot of diversity.  For example, trying to personalize my movie recommendations based on my wife’s tastes would not be a satisfying experience.  Collaborative filtering using people who have common interests with me is a step in the right direction and the interest graph is certainly an important part of that.

However, you can predict more about a person with an opinion graph versus an interest graph. The difference is that while many companies can infer from web behavior what people are interested in, perhaps by looking at the kinds of articles and websites they consume, a graph of opinions actually knows what people think about the things they are reading about.  Anyone who works with data knows that the more specific a data point is, the more you can predict, as the amount of “error” in your measurement is reduced.  Reduced measurement error is far more important for prediction than sample size, which is a point that gets lost in the drive toward bigger and bigger data sets.  Nate Silver often makes this point in talks and in his book.

For example, if you know someone reads articles about Slumdog Millionare, then you can serve them content about Slumdog Millionare.  That would be a typical use case for interest graph data. Using collaborative filtering, you can find out what other Slumdog Millionare fans like and serve them appropriate content.  With opinion graph data, of the type we collect at Ranker, you might be able to differentiate between a person who thinks that Slumdog Millionare is simply a great movie versus someone who thinks the soundtrack was one of the best ever.  If you liked the movie, we would predict that you would also like Fight Club.  But if you liked the soundtrack, you might instead be interested in other music by A.R. Rahman.

Simply put, the opinion graph can predict more about people than the interest graph can.

– Ravi Iyer