My research focuses on machine learning. On the algorithm side, my group invents new machine learning methods for optimal teaching, topological data analysis, semi-supervised learning, and active learning. On the applied side, my group discovers computational models behind interesting human behaviors, and analyzes social media for social good. My group has been supported by the National Science Foundation, National Institutes of Health, AFOSR, and University of Wisconsin-Madison. For a complete list of projects, data sets, and code, please visit my publications page.