Territory Maps of Gangs in Los Angeles

On the subject of interesting uses for Geographic Information Systems (GIS), I ran across this fascinating site, Maps and Territories of Gangs in Los Angeles County, while doing some background reading for a new course I'll be teaching at USC on technology and planning. The author, Alex Alonso, who is himself apparently a PhD candidate in USC's Geography department

1 minute read

July 9, 2004, 4:46 PM PDT

By Chris Steins @planetizen


On the subject of interesting uses for Geographic Information Systems (GIS), I ran across this fascinating site, Maps and Territories of Gangs in Los Angeles County, while doing some background reading for a new course I'll be teaching at USC on technology and planning.



Territory MapThe author, Alex Alonso, who is himself apparently a PhD candidate in USC's Geography department, used ESRI's GIS software to digitize and analyse gang territories in and around Los Angeles. This was one of my favorites conclusions by the author:


This map reveals that gangs with significant territories are concentrated on the Westside portion of the city. On the Eastside, which consists of Watts, and the City of Compton have significantly smaller territories. I determined that the size variation had little to do with population density, but more to do with the temporal aspect of gangs in a particular area. The older more original gang territories were smaller and those gangs that developed in the newer "unclaimed" areas, where able to develop larger territories. This notion is very similar to how the United States developed individual states over time. The older original colonies are significantly smaller than the West coast states that joined the union later.





The Annual ESRI International User Conference is coming up. This would make for a very popular session...



Chris Steins

Chris Stines is Planetizen's former Editor and the founder of Urban Insight, a leading digital agency. Chris has 25 years of experience in technology consulting and urban planning and has served as a consultant to public sector state, county, and local agencies, Fortune 500 private firms, educational institutions, and nonprofit organizations.

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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