Quora's mission is to share and grow the world’s knowledge. On Quora, people ask questions on a wide range of topics and Quora surfaces those questions to people with relevant credentials and experiences so they can respond with an insightful, helpful answer. The more you use Quora—whether it’s to ask a question, answer one, or follow people or topics of interest—the better Quora gets. We’re constantly improving our ability to personalize an experience that’s filled with people, questions, and answers you’ve shown interest in. We achieve this via several machine learning and NLP systems.

In this talk, I will discuss these machine learning and NLP systems in depth. I will explore how we extract intelligence from questions on Quora, including how we do question-topic labeling, how we automatically correct questions with bad spelling and grammar, how we detect duplicate questions, how we learn to rank answers to questions and more. I will explain how the output of these systems supply an important input for the downstream machine learning applications that power Quora. Finally, I will highlight lessons I have learned from applying state-of-the-art machine learning techniques to consumer products at scale.