In this dissertation I investigate postsecondary online education with three research questions: 1. What is the connection between broadband access and the number of students who attempt online coursework? 2. What is the effect of online course delivery on course persistence and, conditional on completion, the likelihood of passing the course? 3.…

The advances in information technologies and the Internet significantly promote the prosperous growth of electronic commerce in recent years. Simply surfing the Internet allows consumers to conveniently explore endless product choices and a flood of related product information. As one of the most important sources of product information,…

The past two decades have shown an unexpected effectiveness of "Web-scale" data in natural language processing. Even the simplest models, when paired with unprecedented amounts of unstructured and unlabeled Web data, have been shown to outperform sophisticated ones. It has been argued that the effectiveness of Web-scale data has…