Lab Members
Alexis Georgeson, Ph.D. -- Principal Investigator
I am an Assistant Professor of Quantitative Psychology at the University of Notre Dame. I earned my Ph.D. in Psychology and Neuroscience from the University of North Carolina at Chapel Hill in 2022. From 2022-2025, I was a Ruth L. Kirschstein National Research Service Award (NRSA) postdoctoral fellow in the Department of Psychology at Arizona State University.
I have long been fascinated by the measurement problems in psychology. After all, measuring abstract concepts like personality or negative affect is not the same as measuring water in a beaker. This interest led me to focus on different approaches to scoring in my graduate studies. In my work, I study when common scoring choices, like sum scores, are sufficient and when latent variable scores might meaningfully change the interpretation of results from a statistical model such as regression or SEM, or in the specific case of a mediation model. Studying measurement invariance in mediation led me to become more interested in mediation more broadly, and my work in mediation has focused on how design limitations may affect conclusions about the mediated effects.
Feel free to get in touch with me if you are looking for a paper, would like to collaborate, or are interested in joining the lab.
Office
E460 Corbett Family Hall Notre Dame, IN 46556
Mahajabin Mostafa, M.S.
Mahajabin is a research assistant at the SiGMA Lab. Prior to joining SiGMA lab, she completed her MS in Engineering Data Science from the University of Houston. Before that, she earned her BS in Computer Science & Engineering from BRAC University in Bangladesh. Her research interest blends data analytics and machine learning to study explainability and trustworthiness in AI systems. She is keen on examining how and why models arrive at their predictions and when that reasoning breaks down. She is also interested in quantitative analysis, particularly through interactive tools like Shiny apps for sensitivity analysis.