Jun Xu is a Full Professor in the Department of Sociology and the Data Science Program at Ball State University. He has a wide range of scholarly interests, including data science, health, and social sciences (history, political philosophy, and sociology), broadly defined. His primary research and teaching interests in data and statistical science include Bayesian inference, causal inference, categorical data analysis, and machine learning. When not at work, Jun loves running, swimming, doing push-ups, tweaking codes, and playing board games (go, chess). He primarily uses R, Stata, and Python for methodological, pedagogical, and substantive projects. His work has appeared in, among others, Comparative Education Review, Social Forces, Social Science & Medicine, Sociological Methods and Research, Social Science Research, and The Stata Journal. He has also published two books--Ordered Regression Models and Modern Applied Regressions--on regression analysis of categorical and limited response variables with Chapman & Hall/CRC.