Degree Name
BS
Department
Cell Biology
College
Life Sciences
Defense Date
2026-05-19
Publication Date
2026-06-12
First Faculty Advisor
Gus Hart
First Faculty Reader
Tyler Jarvis
Second Faculty Reader
Branton Campbell
Honors Coordinator
Amber Gonda
Keywords
Cluster Expansion, Alloy, Generalized Aliasing Decomposition, Predictive Modeling, Computational Physics
Abstract
The cluster expansion (CE) method is a powerful framework for modeling alloy systems by linking atomic configurations to thermophysical properties. However, constructing accurate and robust CE models requires careful selection of both training structures and cluster bases. In this work, we investigate how structure enumeration and cluster selection strategies influence CE performance in binary face-centered cubic alloys using a Julia-based implementation. Model performance is evaluated using empirical risk and the generalized aliasing decomposition (GAD), which provides insight into the relationship between model complexity and generalization error. We find that physically motivated selection strategies that prioritize small clusters consistently outperform approaches focused primarily on numerical stability. We also show that data-driven cluster selection methods have the potential to outperform both approaches and may provide a systematic framework for guiding CE construction. Overall, these results highlight the importance of combining physical intuition with data-driven methods in CE modeling, while demonstrating the usefulness of GAD for understanding complexity–generalization trade-offs. This work explore strategies for selecting clusters and training data in CE models and prompts further study in more complex multi-component systems.
BYU ScholarsArchive Citation
Bills, Samuel D., "Improving Cluster Expansion Efficiency and Generalizability" (2026). Undergraduate Honors Theses. 529.
https://scholarsarchive.byu.edu/studentpub_uht/529