As an undergraduate in her native China, Si Cheng discovered the application of statistics to health through a mathematical modeling class covering public health topics. Intrigued, she decided to pursue her graduate studies in biostatistics. Now in her second year in the master of science program, Si Cheng works with Professor Forrest Crawford studying the contagion effect in social networks. Models for social contagion estimate how the status, behavior and beliefs of ones’ acquaintances influence one’s own situation. Crawford’s group aims to assess how results from these models may be biased from the true mechanism of contagion.
Another research focus of the group is to investigate estimators for hard-to-reach populations, such as drug users or people with HIV. There have been a range of indirect approaches to estimate those “hidden” populations, and determine whether a very large sample size leads to precise estimates . The answer is “not always”, which contradicts the common beliefs of statisticians, says Si.
When not studying, Si relaxes by practicing Chinese calligraphy and participating in the Association of Chinese Students and Scholars at Yale.