Faculty & Staff Directory
- Associate Professor
- Ph.D, Geography, Arizona State University, 2007
- M.A., Geography, Arizona State University, 2004
- B.A., Economics and Geography and Regional Studies, University of Miami (FL), 2002
Timothy (Tim) Leslie is an Associate Professor in the Department of Geography and Geoinformation Sciences. He joined Mason’s faculty in 2007 after launching the Arizona Indicators Project from the Office of President at Arizona State University. He has had affiliations with Mason’s School of Public Health, the Center for Health Policy Research and Ethics, and GIS Center of Excellence.
Dr. Leslie has an extensive history in University organizational leadership. Through three terms in the Faculty Senate, where he spent all but one year on the Executive Committee, Dr. Leslie established a reputation as a pragmatic and energetic driver of collective success. His collaborations and energy were responsible for the creation of the University’s Undergraduate Council, the founding of a Faculty Handbook for the Mason Korea campus, the establishment of minimum faculty salaries paired with substantially increased promotion raises, and the online Dissertation Committee and Dissertation Approval portal along with the related extensive modifications to the University Catalog. In addition to years of service chairing the Faculty Senate Budget and Resources committee and the University’s Academic Initiatives committee, he has also served as the Chair of the College of Science Faculty.
Dr. Leslie’s academic program portfolio includes substantial re-envisioning of both departmental bachelor’s degrees as well as its PhD curriculum, resulting in improved graduation times and reduced administrative overwork. Additionally, he led the creation of a Departmental Honors program for undergraduates, the minor in Business Informatics, and co-creation of the College’s program in Science Leadership and Practice. He is an expert in curricular experience, having established the metrics for each of the department’s doctoral, master’s and bachelor’s programs as well as led departmental efforts in course assessment. In his years of service as Undergraduate Advisor and Academic Associate Chair, he oversaw enrollment increases in the department at triple the rate of Mason’s student body growth with no decreases in time-to-graduation or learning outcomes. He has additional experience through the Mason Mpact Leadership council, the Students and Scholars Faculty and Curricular Affairs committee, and the New Ventures Advisory Council.
In addition to structural improvements, Dr. Leslie has a longstanding practice of mentoring faculty, staff, and leaders at all levels – particularly those new to the institution. His approach is relational and whole person, and he provides valuable support in making sure community members are seen, heard, and provided the guidance they need to thrive at Mason. He has provided additional leadership as a Summer Team Impact Mentor, with the Aspiring Scientists Summer Internship Program, and through the University Undergraduate Apprenticeship program.
Dr. Leslie is an urban-economic health geographer with experience in applying quantitative and geospatial methods to understand and address the influences of socioeconomic and place-based factors on outcomes and inequities across the health and economics domains. His most visible ongoing work has focused on the role of geographic factors, particularly, residential segregation, on health outcomes. You can find a full list of his publications at his Google Scholar or ORCID page.
Following his initial research in the knowledge economy, Dr. Leslie’s urban work began through the characterization and investigation of multiple elements of the economy of Phoenix Arizona, where general and sectoral-specific analysis of Phoenix has shown a substantial structure to the postmodern metropolis. These studies inspired the development of the Co-Location Quotient (CLQ), a metric of point-based categorical association, which has been further developed into a local statistic and integrated into the toolbox of ESRI’s ArcPro. Research has since shifted to the DC metropolitan area, where the federal capital has created a unique structure of producer services. Other urban-economic work has included considerations of migration, residential living space, and the spatial market effects of removing certain types of products from stores.
Dr. Leslie began his research in health outcomes through international research focusing on the effects of macronutrients, demonstrating the importance of ecological elements to diet diversity, micronutrition, and feeding practices. This international work inspired research on the food environment in the DC region, which has been a source of scholarship as well as partnership with the Inova and Children’s National hospital systems. This work has highlighted the importance of more complex food environment constructs, as well as the need to integrate behavior-based elements into health analysis. These efforts grew into a larger collaboration focused on vaccination uptake and exemption behavior, particularly within the context of California and its policies in the 2010s. More recent efforts have centered on the impacts of residential segregation. He has published on how regions with higher racial- and class-based segregation have been linked to higher rates of violence, in general and as seen through police shootings. Additionally, he has demonstrated that more segregated areas have hospitals that result in poorer cancer outcomes, and they have higher rates of opioid deaths.
Dr Leslie’s research has been part of over 4 million dollars in funding, including support from the National Institute of Health, the Robert Wood Johnson Foundation, the Centers for Disease Control, and the General Services Administration. His articles have been published in flagship journals across disciplines including the Journal of the American Medical Association, Annals of the Association of American Geographers, and the American Journal of Public Health among other peer-reviewed journals, with service as an Editorial Board member for Dialogues in Health from 2021 to 2024.
Dr. Leslie’s instruction is rooted in the process of Mastery Learning, which emphasizes completing a set of tasks at a high proficiency before moving forward to subsequent learning and activities. This approach drives a hybrid learning approach that allows students to progress at different rates in coursework and emphasizes outcomes and revision where possible so that all students can achieve success. His instructional experience spans introductory survey courses; Honors College seminars; technical application courses in GIS and spatial statistics; and systematic courses in health, economic, and demographic applications. His primary offerings are:
• GGS 101 - Major World Regions
• GGS 305 / 615 - Economic Geography
• GGS 310 / 551 - Cartographic Design
• GGS 340 / 540 - Health Geography
• GGS 463 / 653 - GIS Analysis and Application
His mentored graduate students now hold positions across academic, government, and industrial careers. He is always open to mentoring new students doing research within his domain of expertise.