Meet Our New PhD Students!

We’ll be featuring mini-profiles of our new PhD students over the next few weeks. We look forward to welcoming them into our community!

Zhiyu Roman YanZhiyu Roman YanHi everyone! I’m Roman Yan. I grew up in Wuhu, a beautiful town sitting on the southeast bank of the Yangtze River in China. I completed my undergraduate study in financial management at Jinan University, where I was exposed to quantitative studies through research projects in financial economics. With that experience, I enjoyed the process of scientific investigation, particularly the application of statistical methods in empirical studies. I then studied in the Department of Mathematical Sciences at Bentley University, where I learned a wider range of statistical methods and received my MS in business analytics.

While my prior educational experiences were around the business context, I have a long-standing interest in medicine and public health. After graduating from Bentley, I embarked on a career as a statistician at Massachusetts General Hospital and am fortunate to have participated in research projects that help understand problems and inform solutions to disparities in patients’ access to care and outcomes, primarily in the contexts of neurology, emergency care, and telemedicine. Through my work, I had a better understanding of the impact of statistics on the robustness and reliability of medical research for various subpopulations, and I am passionate about innovations in statistical methodologies that will advance health equity. During my PhD training, I hope to continue to explore this area as well as other research topics that may capture my interests along the new journey.Outside of academics, I love playing basketball and am eager to experience the vibe of the amateur basketball communities around the Longwood area and Cambridge. I also enjoy playing a traditional Chinese instrument called erhu in my free time. I look forward to meeting everyone!

Elizabeth Yoo GraffElizabeth Yoo Graff

Hello! My name is Liz Graff. Born in Seoul, Korea, I immigrated to Seattle, Washington, as a teenager. I studied mathematics at Columbia University before pursuing a master’s in operations research at Princeton University, where I stayed on as a research assistant.

At Princeton, I focused on healthcare-related projects including modeling COVID-19 trajectories to incorporate patient subgroup structure, improving preprocessing for the MIMIC-IV electronic health records database and detecting mental health disorders with wearables data.During these projects, I noticed a significant limitation: the lack of reliable data for marginalized groups. Unfortunately, these groups tend to experience disproportionately worse health outcomes. At HSPH, I plan to address this disparity by developing robust statistical machine learning algorithms that can handle imbalanced datasets. I am also enthusiastic about building digital health tools that can inform physician decision-making and scale up data collection to better reflect the diverse population we serve. My goal is to democratize access to healthcare through my research.Outside of research, I enjoy rock climbing, yoga and dessert hopping. I look forward to meeting everyone!