The first part of this dissertation conducts a large-scale study comparing general and usage-based indices of syntactic complexity in L2 Mandarin writing samples across a wide range of proficiency levels. To do this, the Tool for the Automated Analysis of Syntactic Sophistication and Complexity (TAASSC; Kyle, 2016) was adapted for Mandarin by…

The emergence of social networks and social media has resulted in exponential increase in the amount of data that link diverse types of richly structured digital objects e.g., individuals, articles, images, videos, music, etc. Such data are naturally represented as heterogeneous networks with multiple types of objects e.g., actors, video,…

This dissertation examines conversations and attitudes about mental health in Twitter discourse. The research uses big data collection, machine learning classification, and social network analysis to answer the following questions (1) what mental health topics do people discuss on Twitter? (2) Have patterns of conversation changed over time? Have…

Digital ecosystems are one of the most important strategic issues in the current digital economy. Digital ecosystems are dynamic and generative. They evolve as new firms join and as heterogeneous systems are integrated into other systems. These features digital ecosystems determine economic and technological success in the competition among…

As teacher collaboration becomes an increasingly common goal in school organization, teachers' experiences and perspectives in a Structured Collaboration Environment remain under-examined. This qualitative case study explored how teachers participated in collaborative work, the outcomes of collaboration, and supports and obstacles to productive…

In the last couple of years, a new aspect of online social networking has emerged, in which the strength of social network connections is based not on social ties but mutually shared interests. This dissertation studies these "curation-based" online social networks (CBN) and their suitability for the diffusion of electronic word-of-mouth…

Data in many growing fields has an underlying network structure that can be taken advantage of. In this dissertation we apply data and network science to problems in the domains of systems biology and healthcare. Data challenges in these fields include noisy, heterogeneous data, and a lack of ground truth. The primary thesis of this work is that…

Biology has been revolutionized in recent years by an explosion in the availability of data. Transforming this new wealth of data into meaningful biological insights and clinical breakthroughs requires a complete overhaul both in the questions being asked and the methodologies used to answer them. A major challenge in organizing and understanding…

Social scientists usually are more interested in consumers' dichotomous choice, such as purchase a product or not, adopt a technology or not, etc. However, up to date, there is nearly no model can help us solve the problem of multi-network effects comparison with a dichotomous dependent variable. Furthermore, the study of multi-network…

The term "librarianship" is a generic one, suggesting one overarching discipline despite the numerous specializations and areas of research within the profession. While many disciplines use bibliometric analysis of their literature to define subfields of study within, such methods are not appropriate to librarianship due to the nature of…

Using a theoretical framework of adolescent social capital, this study examines what one middle school does or does not do to help the students at the school make friends and acquaintances. After reviewing the related literature on adolescent social capital, social network theory, social goal motivation, and best practices middle school…