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!

Christian TestaChristian TestaMy academic interests center on the intersections of causal inference, social and spatial epidemiology (and social justice), and infectious disease modeling. I’ve been working at the Harvard T.H. Chan School of Public Health for the past 6 years— for the first three years, I was in the Department of Global Health and Population working on infectious disease simulation and intervention policy modeling, and for the past three years, I’ve been working in the Department of Social and Behavioral Sciences on health inequities research. My recent projects have focused on the health impacts of discrimination across diverse social identity categories, epigenetic aging mediating the relationship between adverse exposures and negative cardiovascular health, and a paper series on COVID-19. Throughout my work, I’ve become particularly interested in how qualities of data visualization and narratives about data analysis affect the process of persuading decision-makers towards (or away from) decisions that value health and human wellbeing.I am quite passionate about reproducible research and integrating modern data science practices in my work. I organize and run the R User Group at the Harvard Data Science Initiative (https://rug-at- to support the R programming community at and around Harvard University, and we host guest speakers such as prominent/famous R developers and speakers local to the school. Outside of R, I love programming in a wide array of languages (with recent interests in Julia, Rust, and a handful of different web technologies). I’m working towards becoming a professor who can teach their students reproducible data science practices and pass onto them an infectious enthusiasm about data analyses that serve to advance health equity.Outside of my academic interests, I’m quite avid about a wide variety of activities including competitive ballroom dancing, recreational rock climbing, photography (, and when I’m not out & about for research or my hobbies I’m at home with my lovely wife Jane and our incredibly fluffy Samoyed dog Hodu (

Hi!Zhuoran Wei My name is Zhuoran Wei. People usually just call me Joanne. I was born and raised in Nanjing, China. I graduated from Emory University with a Bachelor of Science in Quantitative Science and Human Health in 2021. I then pursued a Master of Science in Biostatistics at HSPH and finished in 2023.

During my undergraduate studies, I did a lot of research works on vector-borne diseases, modeling mosquito population dynamics and disease transmission. I had much experience using GLMMs and zero-inflated models for count data. I also spent tons of time in the fields (e.g. collect mosquitoes and ticks) and in the wet lab (e.g. rear mosquitoes, extract DNA samples from ticks). In my master’s program, I was a research trainee in the Sleep Epidemiology Lab at BWH, cleaning, summarizing and analyzing data from clinical trials. I am interested in various statistical issues in clinical trials, such as missingness, correlated/clustered data, heterogeneity and so on. I also worked on method development for longitudinal analysis, such as second-order GEE for hearing loss studies. For the future, I want to continue to work on clinical trials and longitudinal analysis, and possibly explore other topics as well.

I am a huge cat lover. I have two cats, MaiMai and NiNi. Both of them are very adorable. MaiMai is friendly and welcoming. He sleeps on top of me every night (but he is very heavy). NiNi is very sweet but shy around strangers. She purrrrs (loudly) a lot! During my spare time, I enjoying spending time with my cats, and watching TV series and anime. excited (and nervous) to begin this new chapter!