The NSF ECR Building Capacity of STEM Education Research (BCSER) program contributes to the NSF mission 42 U.S. Code Chapter 16 by building the US workforce undertaking STEM education research. The BCSER Individual Investigator Development in STEM Education Research (IID) track supports individual investigators who are experienced STEM education researchers to develop expertise in new areas that will contribute to advancing STEM education knowledge. STEM education research generates the knowledge, theories, and understandings on which viable strategies for improving U.S. STEM education and workforce outcomes are based. This project will advance knowledge about how to ensure more rigorous, accurate, and precise multilevel models for quantitative analyses of STEM Education data via the use of Bayesian methods. This BCSER IID project will allow the PI to supplement their current expertise with new research skills to design and implement cutting edge STEM education research using Bayesian hierarchical modeling, Bayesian multiple imputation, and the integration of theory-informed priors. The project will also enable the PI to receive mentoring from STEM education mentors who specialize in theory related to and application of Bayesian methods and Multilevel analysis of individual heterogeneity and discriminatory accuracy. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader