How can large-scale machine learning be used to build products? At LinkedIn, the latest "data feature" in our portfolio is Endorsements, a mechanism to recognise someone for their skills and expertise. This ecosystem is generating a large graph of reputation signals: over 1B endorsements have been made in the few short months since the product launched.

How were we able to do this? In this talk, I'll deep dive into technical detail of our approach and the practical aspects of building a data feature like Endorsements. I'll go into how we extract a taxonomy of skills, how we determine if someone possesses a skill, and how we use that knowledge to recommend people to endorse. I'll also detail some of our open-source Hadoop-based infrastructure that allows us to put this into a productionized process.