Don’t Use Zip Codes in Geospatial Analysis

Matt Forrest of Carto says we should stop using Zip codes in geospatial analysis.

Even though there are different place associations that probably mean more to you as an individual, such as a neighborhood, street, or the block you live on, the zip code is, in many organizations, the geographic unit of choice. It is used to make major decisions for marketing, opening or closing stores, providing services, and making decisions that can have a massive financial impact.

The problem is that zip codes are not a good representation of real human behavior, and when used in data analysis, often mask real, underlying insights, and may ultimately lead to bad outcomes.

Zip codes, Matt says, are arbitrary: too many things going on at a local level can be missed if they don’t line up with zip code boundaries (such as the Flint water crisis). He does offer some alternatives: census tracts, spatial indices and good old fashioned addresses.

Meanwhile, on Twitter, Bill Morris defends the use of Zip codes: yes, they’re overused; yes, they should only be used in the worst case; but they may be the only local unit a client or user will find easy to understand.

A Map of Hard to Count Communities for the 2020 U.S. Census

The HTC 2020 map is an interactive map of hard-to-count communities built for campaigns to increase participation in the United States’s 2020 census. Hard-to-count communities are populations that historically have a poor self-response rate: they return their census forms online or by mail at lower rates, requiring followup interviews by enumerators. The map shows response rates by census tract, and notes the demographics of each tract in terms of why the response rates might be low: lack of Internet access, or large numbers of people who are historically undercounted (poor, rural, people of colour). [NYPL]

Map of UV Exposure in the United States

NASA Earth Observatory (Joshua Stevens)

NASA Earth Observatory:

The NASA Applied Sciences Program has partnered with the Centers for Disease Control and Prevention (CDC) to create the first publicly available map of ultraviolet (UV) radiation for all counties in the contiguous United States. The dataset, which spans 2005-2015, is available on the CDC’s National Environmental Public Health Tracking network, which delivers information and data about health issues related to environmental factors. Public health officials, city planners, or individuals concerned about Sun exposure can learn how much ultraviolet radiation is falling over each county each month, which is an important step in helping reduce skin cancer risks.

The animated map above shows the monthly average UV dose in 2015.

Mapping the Opioid Crisis

Washington Post

Last month the Washington Post gained access to ARCOS, the U.S. Drug Enforcement Agency’s database of controlled substance transactions, which tracks the path, from manufacturer to pharmacy, of every pain pill in the United States. The Post’s initial analysis found that some 76 billion oxycodone and hydrocodone pills were distributed in the U.S. between 2006 and 2012, that only a few companies manufactured and distributed the bulk of the pills, and some regions of the country were utterly saturated with the pills. That’s where the maps come in: the Post has county-level maps of all this data.

Comparing county-level maps of opioid overdose deaths and pill shipments reveal a virtual opioid belt of more than 90 counties stretching southwest from Webster County, W.Va., through southern Virginia and ending in Monroe County, Ky. This swath includes 18 of the top 20 counties ranked by per-capita prescription opioid deaths nationwide and 12 of the top 20 counties for opioid pills distributed per capita.

Revealing. Damning. Horrifying.

The New York Times Maps Democratic Donors

The New York Times

In a series of maps, the New York Times explores where the donors to the various Democratic candidates for U.S. president live. The maps are based on data to June 30, and include donations of $200 or more. Bernie Sanders has by far the most donors so far, and they’re distributed broadly, so the second map on the page excludes Sanders donors to tease out where other candidates’ donors are concentrated regionally.

New Leventhal Exhibition: America Transformed

The Leventhal Map Center’s latest exhibition, America Transformed: Mapping the 19th Century, opened last Saturday and runs until 10 November 2019.

During the 19th century, the United States expanded dramatically westward. Immigrant settlers rapidly spread across the continent and transformed it, often through violent or deceptive means, from ancestral Native lands and borderlands teeming with diverse communities to landscapes that fueled the rise of industrialized cities. Historical maps, images and related objects tell the story of the sweeping changes made to the physical, cultural, and political landscape. Moving beyond the mythologized American frontier, this map exhibition explores the complexity of factors that shaped our country over the century.

As usual, there’s a comprehensive online version, which is peppered with acknowledgements of the very white, very settler-colonialist perspective of the maps on display. Which are, of course, justified, but as far as I can see they’re asterisks and asides on an otherwise unchanged exhibit.

Mapping Disasters in America

The Washington Post maps disasters in the United States, with a page that shows maps of flood warnings, tornadoes and hurricanes, extreme heat and cold (see above), wildfires, lightning, and earthquakes and volcanoes. In the wake of a natural disaster there’s usually someone suggesting that the victims are at fault for living in a disaster zone. The WaPost’s maps have an answer to that: “It turns out there is nowhere in the United States that is particularly insulated from everything.”

Measles in America

The New York Times (screenshot)

The New York Times maps confirmed measles cases in the United States as of April 29, 2019. “Measles was declared eliminated in the United States in 2000 but the highly contagious disease has returned in recent years in communities with low vaccination rates. The number of cases reported this year is already nearly double last year’s count and has surpassed the previous post-elimination high of 667 cases in 2014.”

The Geography of Partisan Prejudice

The Atlantic maps political polarization in America. “The result was surprising in several ways. First, while virtually all Americans have been exposed to hyper-partisan politicians, social-media echo chambers, and clickbait headlines, we found significant variations in Americans’ political ill will from place to place, regardless of party.” Includes an interactive map with county-level data based on polling and analytics.

The Washington Post Maps the U.S.-Mexico Border

The print edition of today’s Washington Post maps the fences and walls along the U.S.-Mexico border. The online version, which I seem to have missed when it was posted in October, offers a much more detailed look: it’s an interactive, scrollable map that offers a flyover view of the border, fenced and unfenced, as it passes through farms, ranches, towns and impossibly rugged terrain between the Pacific and the Gulf of Mexico.

How America Mapped Its Meals

A Fine and Fertile Country: How America Mapped Its Meals, an exhibition at the Harvard Map Collection, runs through 1 March 2019. “Harvard’s maps of American agriculture, ranging from the colonial period to current GIS data, demonstrate how food production has been a matter of concern ever since the first colonists arrived. The history of finding and farming food in the United States is a story of culture and convenience, capitalism and cattle drives. Academic arguments aside, once you see what the maps will show you, you might never look at apples and potatoes the same way.” No online version yet.

A History of America in 100 Maps

In my review Tuesday of Tom Harper’s Atlas: A World of Maps from the British Library, I spent some time talking about the choices made when assembling a collection of maps. Susan Schulten’s third (solo-authored) book, A History of America in 100 Maps, out now from the University of Chicago Press in the Americas and the British Library in the U.K., also draws upon the British Library’s map collection, particularly in the early chapters. (This may come as a surprise, seeing as it’s a book about America.) In a few instances the same map makes an appearance in both books. But in terms of what the two books do with the maps, their approaches are quite different.

Schulten, a history professor at the University of Denver, is the author of The Geographical Imagination in America, 1880-1950 (University of Chicago Press, 2001) and Mapping the Nation: History and Cartography in Nineteenth-Century America (University of Chicago Press, 2012). These are social histories of maps and mapmaking, which is very much my kind of thing, and I’ve been meaning to check out Schulten’s (and Martin Brückner’s) work for some time. From what I gather, Schulten’s work focuses on how maps were made and used—the function of maps.

Continue reading “A History of America in 100 Maps”

United States of Apathy

United States of Apathy (Philip Kearney)

In April amateur cartographer Philip Kearney created “United States of Apathy,” a map that imagined the 2016 U.S. presidential election results if nonvoters were counted as a vote for “nobody,” in which case “nobody” would have won the electoral college by a landslide. Esri cartographer Jim Herries recently collaborated with Kearney on an interactive version that explores the phenomenon of apathetic voters in more depth. [CityLab]

Emma Willard’s History of the United States

David Rumsey Map Collection

Atlas Obscura looks at the cartographic work of early American educator Emma Willard, who in 1829 published a series of maps to accompany her History of United States, or Republic of America, a school textbook that came out the previous year. The book was an early example of a historical atlas: it was “the first book of its kind—the first atlas to present the evolution of America.”