Los Angeles Times
Mapping L.A. is the Los Angeles Times’ growing resource about the neighborhoods that make up Los Angeles County. It provides maps and information about demographics, crime and schools in 272 neighborhoods across the county.
How are neighborhoods determined?
The neighborhoods are drawn and maintained by the Data Desk, a team of Times reporters and Web developers in downtown L.A. The boundaries have expanded and shifted over time and now cover all of Los Angeles County broken down into 272 neighborhoods.
The Times released the first draft of 87 neighborhoods in February 2009. That group was limited to neighborhoods within the city of Los Angeles and crafted by merging together neighboring census tracts.
Census tracts are drawn by the U.S. Census Bureau and used for tabulating demographic information, including income and ethnicity. The shapes of the tracts are frequently out of sync with the geographical, historic and socioeconomic associations that define communities. However, by using the tracts as building blocks, The Times was able to compile a statistical profile of communities, something other neighborhood boundaries do not offer.
Besides merging tracts, we’ve adjusted the lines in many cases by moving individual city blocks from one census tract to another. In each instance, we’ve adjusted the census data in proportion to the relocated block’s population.
When we posted the first draft of the map, we invited users to send us comments and draft revisions. We received more than 650 user-generated maps, ranging from the precise to the bizarre.
After nearly 100 revisions, a map of 114 city neighborhoods was released in June 2009.
In June 2010, the map was expanded beyond the city to cover all of Los Angeles County. The neighborhood total more than doubled to 272 as cities as varied as Santa Monica and Industry and unincorporated areas such as Valinda and Lake Hughes landed on the map.
To define neighborhoods across the county, The Times primarily used the U.S. Census Bureau’s boundaries of 88 cities and 43 census-designated places set aside for special tabulation. The Census Bureau maps were adjusted in some areas to conform to more recent maps produced by the Los Angeles County Department of Regional Planning. In addition, The Times adopted 12 unincorporated areas proposed by the county for future designation as census places. In rare instances, the census place names were changed to reflect the names used by residents.
The remaining unincorporated areas that have not been designated by the Census Bureau or the county were generally named with a compass reference to their closest city, such as Unincorporated Carson-West.
Large rural areas were divided, as much as possible, using rivers, ridgelines or highways and given generic names.
There are 42 small unincorporated areas that either closely adjoin or are entirely within a city. For statistical purposes, The Times combined those areas with the cities. Thus the profiles of those cities will not be exactly match census publications.
Why does The Times portray L.A. neighborhoods differently than other sources?
The city of Los Angeles has posted hundreds of blue street signs denoting scores of neighborhoods — from Little Ethiopia to Little Tokyo to Little Armenia. But the city has never drawn the official boundaries of those districts.
The Thomas Guide shows the names of many communities but does not try to make clear where neighborhood boundaries are.
Neighborhood councils within the city sometimes reflect narrow political considerations, and many have a propensity for names like People Involved in Community Organizing, which don’t do much to define a community. Many areas of the city have no neighborhood council, even as prized turf such as Occidental College is claimed by more than one council. The same problems apply with even greater force to homeowner associations.
ZIP Codes provide many people with a community identity but are designed only to speed up the mail. That’s a nice fit in some places but unworkable in others, such as the part of Los Angeles that falls in Beverly Hills 90210. Van Nuys and North Hollywood each have four ZIP Codes. And dozens of ZIP Codes within the city are identified only as Los Angeles.
Unlike most other attempts at mapping L.A., this one follows a set of principles intended to make it visually and statistically coherent: It gathers every block of the city into reasonably compact areas leaving no enclaves, gaps, overlaps or ambiguities. Except when there was a compelling reason not to, we kept schools and other landmarks in the communities bearing their names.
We’ll be the first to acknowledge that our map isn’t perfect. No lines can capture the geographic diversity and demographic energy of Los Angeles.
Why draw lines at all?
Consistency is one reason. If we report that an event occurred in Van Nuys or Westwood, we want people to know exactly where we mean.
Analysis is another. Defining a strict set of boundaries allows The Times to package a wealth of data for our readers — about demographics, income, crime, schools and more — in common geographic units. Neighborhoods are easier to digest than arcane statistical areas like census tracts, and when many data sources are combined at the neighborhood level, they can yield new and interesting insights.
Why are some cities referred to as neighborhoods?
In order to standardize how we refer to areas included in Mapping L.A., The Times uses the term neighborhood to encompass everything from unincorporated areas to standalone cities to neighborhoods within cities.
For now, only the city of Los Angeles is broken up into smaller neighborhoods. However, there are plans to divide a number of the larger cities, including Long Beach, Santa Monica and Pasadena, in order to better reflect how people live their daily lives.
What technology did The Times use to make this website?
This site is built entirely with free and open-source software, including Django, Leaflet, jQuery, OpenLayers, Timemap and PostgreSQL. Thank you to all of the community members who have contributed to their development. Thanks must go especially to the GeoDjango project, which provides an astounding tool for publishing data with a geospatial database.
One note on accuracy. In order to publish maps in your Internet browser, we’ve often had to simplify the complex electronic shapes and sacrificing a bit of precision to improve the user experience.
Essentially, each neighborhood boundary consists of many points with lines connecting them to one another. Lots of points are needed to conform to curved or crooked boundaries. We used the Douglas-Peucker algorithm to reduce the number of points for faster performance. This will sacrifice some precision, but is necessary to accommodate users with older computers and browsers.
How can I get a copy of the data?
The Times neighborhood boundaries are available for use under a Creative Commons Attribution-Share Alike license. That means you can share and remix them for work as long as you credit The Los Angeles Times and release your creations under the same terms.
The boundaries can be downloaded below. Unfortunately, we cannot provide custom data. However, it can sometimes be possible to provide custom forms of information by contacting Erica Varela in Rights and Permissions. Note that minimum fees are generally $500.
Los Angeles Times