Ofer Mendelevitch is director of data science at Hortonworks, where he is responsible for helping customers realize the benefits of Big Data through data science with Hadoop. Prior to joining Hortonworks, Ofer served as entrepreneur in residence at XSeed Capital, VP of engineering at Nor1, and director of engineering at Yahoo!, where he led multiple engineering and data science teams responsible for R&D of large-scale computational advertising projects, including CTR prediction (with Hadoop), a new front-end ad-serving system, and sales tools. Ofer lives in the Silicon Valley in California.