The document provides an overview of big data analytics for healthcare. It begins with motivating examples that demonstrate how big data can help improve healthcare outcomes and lower costs. It then discusses the main sources of healthcare data, including structured EHR data like billing codes, labs, and medications, as well as unstructured clinical notes. The document outlines challenges in analyzing these different types of complex healthcare data. It also introduces a healthcare analytics platform that can extract and select features from various data sources to build predictive models. Finally, it discusses techniques for clinical text mining, including named entity recognition and negation analysis.