Tongyun Li is a senior psychometrician in the Psychometric Analysis and Research area of the Research & Development division at ETS. She received her Ph.D. in measurement, statistics, and evaluation in 2014 and her M.Ed. in human development specializing in educational psychology in 2011 from the University of Maryland, College Park. She also earned a B.A. in international business communication from Nanjing University in 2009. She has research experience with mixture and multilevel item response theory models and Bayesian inference. Since joining ETS in 2015, she has worked on the TOEFL iBT®, the TOEFL Junior® and the TOEFL ProPlacer® tests.