COGS
@
SDSU

The Center for Open Geographical Science launched in 2022 as a hub for open and reproducible research and a home for all things spatial. COGS combines expertise from two collaborative research labs: the lab for Spatial Analysis in the Social Sciences (SASS) and the Vegetation and Landscape Ecology (VALE) lab

Collaborative & Interdisciplinary Research

We integrate spatial analysis into disciplines ranging from housing and education, to public health and epidemiology, to paleoecology and plant sciences. COGS leverages expertise in spatial data science and collaborates with colleagues across the globe to answer pressing questions in social and natural sciences

Open and Reproducible Science

Researchers at COGS specialize in open-source software development and fully-reproducible scientific workflows. Science is better when it’s open, collaborative, and shared with the community

Join Us

Welcome to COGS

The Center for Open Geographical Science

SASS

The Lab for Spatial Analysis in the Social Sciences (SASS) examines patterns of urban spatial structure and their interactions with the dynamics of economic, demographic, education, public health, and other social systems. We apply spatial econometrics, urban data science, and geospatial statistics to study issues of inequality in social science and public policy. We devise new spatially-explicit research methods and develop open-source software to support honest and reproducible science.

Work by SASS

VALE

The Vegetation And Landscape Ecology (VALE) Lab examines patterns and dynamics of terrestrial ecosystems at the landscape scale. We study the impacts of human-caused landscape change on terrestrial plant communities. The tools we use include field measurements of e.g., plant community composition, multivariate analysis, spatial statistics, landscape simulation models, and geospatial data analysis (GIS and Remote Sensing).

Work by VALE More from VALE

Research Expertise

Spatial Statistics

Spatial Econometrics

Spatial Optimization

Open Source

Python

R

Sustainability

Social Justice

Urban & Environmental Analytics

The Latest News from COGS

COGS Director Rey Publishes New Paper on Measurement of Spatial Inequality

From the paper: Abstract. This paper explores the concepts and computational methods used to measure spatial inequality, emphasizing a reproducible approach that social scientists can apply to their research. The analysis focuses on geographic income disparities at the sub-national level, using Mexico as a case study.

Sergio Rey

May 23, 2025 1 min read

COGS Director Rey Publishes New Paper on Measurement of Spatial Inequality

COGS Receives NSF Pathways to Open Source Ecosystems (POSE) Grant

The COGS team has received a prestigious $1.5M award to transform the Python Spatial Analysis Library (PySAL) into a fully-fledged open-source ecosystem by engaging academia, government, and scientific partners. Read more on the grant page

Sergio Rey, Elijah Knaap, Wei Kang

May 23, 2025 1 min read

New Paper by COGS and UCR examines the Landscape of Overdose in Inland California

From the paper: Abstract. This paper explores the concepts and computational methods used to measure spatial inequality, emphasizing a reproducible approach that social scientists can apply to their research. The analysis focuses on geographic income disparities at the sub-national level, using Mexico as a case study.

Jennifer Leigh Syvertsen, Sergio Rey, Elijah Knaap

Apr 23, 2025 1 min read

New Paper by COGS and UCR examines the Landscape of Overdose in Inland California

Professor Janet Franklin Delivers 13th Virginia & J. Edward Holtry Distinguished Lecture in Geospatial Science at South Dakota State University

On October 14, 2024, San Diego State University geographer Janet Franklin was invited to give the 13th Virginia & J. Edward Holtry Distinguished Lecture in Geospatial Science at ‘the other SDSU’ – South Dakota State University.

Janet Franklin

Oct 14, 2024 1 min read

COGS Team Receives NSF-POSE Grant to Enhance PySAL into Open Source Ecosystem

In collaboration with partners at the University of Chicago, University of Maryland, and the University of California, Riverside, COGS has been awarded a POSE grant from the National Science Foundation focused on the open-source Python Spatial Analysis Library (PySAL), which has been downloaded over two million times.

Sergio Rey, Elijah Knaap, Wei Kang

Aug 24, 2024 2 min read

COGS Director Sergio Rey Elected Fellow of the American Association for the Advancement of Science

COGS is ecstatic to announce that Director Sergio Rey has been elected a fellow of the American Association for the Advancement of Science. Rey is recognized for work as a leading pioneer of the Python Spatial Analysis Library (PySAL), downloaded two million times.

Sergio Rey

Apr 23, 2024 1 min read

Dr. Brooke Rose Receives Two Prestigious Awards at AAG 2024

Dr. M. Brooke Rose, a postdoctoral scholar working with Professor Janet Franklin in the Center for Open Geographical Sciences, Department of Geography, receives both the Cowles award for Best Paper in Biogeography, and an award for the AAG Biogeography Specialty Group (BSG) Student Paper Award in the Doctoral Category.

Brooke Rose

Apr 19, 2024 2 min read

Professor Franklin Shares Invited Perspective in the 50th anniversary year of Journal of Biogeography

I reflect on developments in species distribution modelling, illustrate how embedded the methodology has become in all areas of biogeography and speculate on future directions in the field. Areas of progress in SDM that may become more widely accessible and useful tools in biogeography include genetically informed models and community distribution models

Janet Franklin

Jan 23, 2024 1 min read

Professor Franklin Shares Invited Perspective in the 50th anniversary year of Journal of Biogeography

Associate Director Knaap elected to the North American Regional Science Council

The mission of the North American Regional Science Council (NARSC) is to promote the scholarly exchange of ideas and knowledge that apply to urban and regional phenomena in North America and across the globe.

Elijah Knaap

Oct 23, 2023 1 min read

Associate Director Knaap elected to the North American Regional Science Council

New Paper by Knaap and Rey Examines Travel Networks and Racial Segregation

In a new paper published in Environment and Planning B: Urban Analytics and City Science, SASS scholars Knaap and Rey show the importance of considering features of the built and natural envrironment–especially transportation networks, when measuring racial residential segregation.

Elijah Knaap, Sergio Rey

Aug 29, 2023 1 min read

New Paper by Knaap and Rey Examines Travel Networks and Racial Segregation

New Book by Rey, Arribas-Bel, and Wolf Geographic Data Science with Python by CRC Press.

From the publisher: This book provides the tools, the methods, and the theory to meet the challenges of contemporary data science applied to geographic problems and data. In the new world of pervasive, large, frequent, and rapid data, there are new opportunities to understand and analyze the role of geography in everyday life.

Sergio Rey, Dani Arribas-Bel, Levi John Wolf

Jun 22, 2023 1 min read

New Book by Rey, Arribas-Bel, and Wolf Geographic Data Science with Python by CRC Press.

New Paper by VALE Researcher Brooke Rose Published in *Global Ecology and Biogeography*

Brooke Rose, PhD candidate working with Janet Franklin in the VALE group, published the first chapter of her dissertation in the high-ranking journal Global Ecology and Biogeography, entitled “Rarity, geography, and plant exposure to global change in the California Floristic Province.

Janet Franklin

Feb 8, 2023 1 min read

New Paper by VALE Researcher Brooke Rose Published in *Global Ecology and Biogeography*

SASS Presents New Paper Examining the Link Between Neighborhood and School Boundaries at WRSA

In a (another) special session honoring SDSU’s renowned Professor of Geography Art Getis, SASS researchers will present a new paper at the 2023 annual meeting of the Western Regional Science Association.

Sergio Rey, Elijah Knaap

Feb 8, 2023 1 min read

SASS Presents New Paper Examining the Link Between Neighborhood and School Boundaries at WRSA

The Handbook of Spatial Analysis in the Social Sciences is Published

The brand new Handbook of Spatial Analysis in the Social Sciences, edited by COGS Director Serge Rey and Rachel Franklin is published in November. The handbook includes chapters from Director Rey and Associate Director Eli Knaap, as well as several COGS affiliates including Ran Wei, Levi Wolf, Dani Arribas-Bel, Wei Kang, and many more

Sergio Rey, Elijah Knaap, Levi John Wolf, Ran Wei, Dani Arribas-Bel, Wei Kang

Oct 19, 2022 1 min read

The Handbook of Spatial Analysis in the Social Sciences is Published

New Study Classifies the Entire Planet’s Ecosystems for the First Time

A global cross-disciplinary team of scientists, including Janet Franklin, San Diego State University biogeographer and National Academy of Sciences member, led by University of New South Wales, Sydney researchers, has developed the first comprehensive classification of the world’s ecosystems across land, rivers, wetlands, and seas.

Janet Franklin

Oct 13, 2022 1 min read

New Study Classifies the Entire Planet’s Ecosystems for the First Time

COGS Honors the Late Arthur Getis at NARSC 2022

In a special session honoring SDSU’s renowned Professor of Geography Art Getis, COGS researchers will present a new paper based on one of Getis’s most famous contributions to the field: the $G_i$ statistic.

Elijah Knaap, Sergio Rey

Oct 12, 2022 2 min read