Digital channels like search engines, online social networking websites and smartphones has revolutionized the way marketers communicate. Successful strategies demand the right consumer insights and effective reading of the social landscape.They are also all driven by data, in some sense. However, it is extremely difficult to get a handle on all the data that consumers leave behind in digital channels. The talk will introduce the background of digital marketing and the challenges in data collection, data storage, data cleaning & Integration, and data mining. The talk will also show a case study on retailer sales driver analysis using ensemble learning. Lanhui Wang accepted her PhD in the field of Applied & Computational Mathematics from Princeton University. She is currently serving as a data scientist for MaxPoint Interactive, Inc, a digital advertising company. Prior to MaxPoint, she worked at TripAdvisor on Search Engine Marketing. Her major projects include bidding strategies in online auctions, and retailer traffic/sales lift measurement and analysis. She is interested in statistical learning and matching learning.