At Quora our mission is to share and grow the world’s knowledge. In order to accomplish this we need to build a complex ecosystem where we value issues such as content quality, engagement, demand, interests, or reputation. On the other hand, the ecosystem itself, generates lots of very good quality data on which to build machine learning solutions that can help address all of our requirements. In this talk I will describe uses of machine learning at Quora that range from different recommendation approaches such as personalized ranking to classifiers built to detect duplicate questions or spam. I will describe some of the modeling and feature engineering approaches that go into building these systems. I will also share some of the challenges faced when building such a large-scale knowledge base of human-generated knowledge.
