Li Yi, PhD (he/him/his) is a Thomas O. Pyle Research Fellow in the Department of Population Medicine at Harvard Medical School and Harvard Pilgrim Health Care Institute. Li has focused his research on investigating the impact of the neighborhood built environment and greenness on health behaviors and chronic disease outcomes. His current work intersects the fields of environmental epidemiology, health behavioral research, and bioinformatics by integrating smartphones and wearable devices, Big Data analytics, and geographic information systems (GIS) into large prospective cohort studies, including Nurses' Health Studies, Growing Up Today Study, Project Viva, and Maternal and Developmental Risks from Environmental and Social Stressors Study. In the Division of Chronic Disease Research Across the Lifecourse (CoRAL), Li is currently working with Drs. Peter James, Izzuddin Aris, Marie-France Hivert, and Emily Oken on several analyses examining the impact of neighborhood characteristics such as greenness exposure, deprivation, walkability on maternal and child health outcomes. Li holds an interdisciplinary PhD in Population, Health and Place from the University of Southern California, an MS in Architectural and Urban Conservation from the University of Pennsylvania, and an MSc in Urban Planning from the University College London.