Big data refers to data so large, varied and generated at such an alarming rate that is too challenging for the conventional methods, tools, and technologies to handle it. Generating value out of it through analytics has started gaining paramount importance. Advanced analytics in the form of predictive and prescriptive analytics can scour through big data in real time or near real time to create valuable insights, which facilitate an organization in strategic decision making. The purpose of this paper is to review the emerging areas of big data and analytics, and is organized in two phases. The first phase covers taxonomy for classifying big data analytics (BDA), the big data value chain, and comparison of various platforms for BDA. The second phase discusses scope of research in BDA and some related work followed by a research proposal for developing a contextual model for BDA using advanced analytics.