Archive for the 'Demographics' Category

WalkScore Heat Maps

Anyone who lives in a city can tell the walkable neighborhoods–with a vibrant street scene, welcoming shops and restaurants, and high accessibility–from the remote, cold office and industrial complexes that are the bane of urban living.  Since July 2007, WalkScorehas been quantifying and mapping the “walkability” of neighborhoods throughout the country.

The map above is a “heat map” walkability chart of Seattle, one of WalkScore’s most recent additions.  The site’s algorithm plots the locations of businesses, restaurants, shops, and other popular destinations block by bloc across a city.  Red areas are car dependant, meaning that there are a small number of accessible destinations spread out across a large area.  Green areas are just the opposite–lots of destinations in a smaller area.

The map of Seattle shows how the neighborhoods vary in their walkability, with downtown and the north-central part of the city registering high walk scores, and the coastal and southwest parts of the city registering low walk scores.  Click here or on the picture above to see the full, zoomable map.

For folks without cars, try to live in the green neighborhoods–it means you can accomplish most of your errands on foot!

[via Greater Greater Washington]


Where the Greenies Live

“Green” economics is a major trend these days.  There are environmentally friendly cars, houses, light bulbs, and laundry detergent–all components of a larger green lifestyles.  But as with all trends, living green is more popular in certain places than in others.  Today’s map is drawn from a study that attempts to chart areas with large numbers of people who live environmentally conscious lifestyles.

The map above is taken from “Green Market Geography: The Spatial Clustering of Hybrid Vehicle and LEED Registered Buildings” by Matthew E. Khan and Ryan K. Vaughn, both economists at UCLA.  This map–a distribution of Prius registrations in Los Angeles County, California–is just one of several maps they include in their paper to show the distribution of the green lifestyle across the state.  Here, the darker the green, the more Prius registrations there are in that zip code.  Click here or on the picture above to see a larger version of the map.

The map indicates that the residents who live along the southern California coast–undoubtedly the wealthier, more highly educated demographics–are more likely to own a Prius than those living further inland.  Despite this coastal trend, however, Khan and Vaughn speculate that there is an additional clustering effect–that green-minded individuals are drawn together into communities by other factors:

Small initial differences in exogenous spatial attributes such as proximity to the ocean can have a social multiplier effect. As environmentalists move to a nice community, green businesses such as organic restaurants would be more likely to locate near this community (Waldfogel 2007). This creates a virtuous cycle attracting even more environmentalists to move to the community. As environmentalists cluster in such communities, they vote for public goods/taxes bundles that further re-enforce this process (i.e bike lanes and recycling bins).

Khan and Vaughn developed an environmentalism scale for the state, based on the number of registered members of the California Green Party, and votes on two binding, statewide ballot initiatives focusing on environmental causes.  This analysis was the foundation of the map below:

In this map, as in the map above, the greener the zip code the more environmental friendly it is on the Khan and Vaughn scale.  Click here or on the picture above to see an enlarged version of the map.  Interestingly, whereas Prius distributions are aligned most closely with wealthier areas by the coast, the environmental ratings statewide do not hew closely to this model.  On the contrary, it seems that a green consumer lifestyle does not necessarily collolate with favorable opinions of environmentalism, including registration with the Green Party.  It turns out you can make environmental choices without owning a Prius.

The information for this post came via this excellent article in the Economist. 

Living the Single Life

A great deal of ink has been spilled trying to show single men and women how to find a partner.  Dating guides, pick-up manuals, support groups, and recent major motion pictures have covered the subject forwards, backwards, and sideways.  But singles looking for love could do worse than to examine the odds: some cities simply have more single men than single women, and others are overflowing with single women but have a dearth of available men. 

The map above, produced by by Richard Florida at, shows the distributions of single men and women between the ages of 20 and 64 in cities nationwide.  Cities with a surplus of men are in blue; those with a surplus of women, in red.  The larger the circle, the greater the number of single men or women in that town. Click here or on the picture above to see an enlarged version of the map.

The trends in the map are easy to spot: men living on the West Coast can probably attest to the huge numbers of single men on the lookout for available women.  And as the characters of Sex and the City attest, New York is crawling with single women but many fewer single men.  Overall, single women seem to gravitate to the Eastern United States, whereas single men apparently head west. 

Perhaps unsurprisingly, most major US metropolitan areas seem to be fairly well balanced; they may have a couple thousand more single men than women or vice versa, but spread out over a large urban area those numbers are barely noticeable.  But cities like New York, Philadelphia, Baltimore, and Washington stand out for their numbers of available women, just as Los Angeles, Phoenix, Dallas, and San Francisco/San Jose stand out for their numbers of single men. 

These statistics belie hidden demographics: certainly, economic centers of male-heavy industries like computing (Silicon Valley), gaming (Las Vegas), and aerospace (Seattle) are likely to attract more single men.  Similarly, many women looking to establish careers in public policy and law (Washington, DC) and fashion and design (New York) will gravitate to the more liberal East Coast cities, perhaps away from more conservative Central and Western states. 

America and Russia: Beyond Borders

In the waning days of the Cold War, a first-rate team of American and Russian geographers began to ask whether the Soviet Union and the United States could be compared on common geographical principles.  The team speculated that geographic similarities–such as the tropics of Florida and of the Black Sea coast, the Appalachians and the Urals, and the Mississippi and the Volga basins–reflected fundamental similarities between the two historically feuding superpowers.  They wrote a book called Beyond Borders to explain their remarkable findings, but at the last minute their publisher was sold and publication of the book was cancelled.  Now, 18 years later, the team has made the book available online in its entirety, for free.

The researchers’ objective was to develop a rubric for comparing Russia and America based on their geographic regions and common history:

While we do not try to minimize the differences between Russia and America, we observed that people in the two countries have many similarities in the way they spread across the continents, adapted to various environments, conquered or absorbed indigenous people, and molded their respective geographies into a set of regions.

The team identified eleven regions on which to base their analysis:

The Core: In America, this roughly corresponds to the Mid-Atlantic Region; in Russia, it means the areas around Moscow and the Upper Volga–the regions that are “what would become all that one could define as uniquely American or Russian.”  This is the traditional “homeland”–Philadelphia, Washington, and New York City in America; and Moscow, Nizhny Novgorod, Yaroslavl, and Tver in Russia.  This is locus of national cultural origin.

The North: In America, this is New England and the northern parts of the Midwestern States on the Canadian border, such as Michigan, Wisconsin, and Minnesota.  In Russia, this includes Novgorod, St. Petersburg, and the coast of the White Sea.  This region is home to Puritanical and Orthodox traditions–an original national ideological home that has since been outpaced by the development it inspired elsewhere.

The South: In America, this roughly means the states that seceded during the Civil War–from the Potomac in the north to central Texas in the southwest.  In Russia, this means central Ukraine into south-central Russia, bordering the Volga.  These regions are defined by their warm weather and arable land, but also by their history of forced servitude through serfdom and slavery. 

The Heartland: In America, this area corresponds with most of the Midwest, from Milwaukee to Cincinnati and Pittsburgh to Buffalo.  Russia’s “Heartland” centers on the junction of the Volga and Kama rivers, near Kazan, Samara, and Ufa.  This is the traditional industrial backbone–a land of factories, labor, and hard work, turned to rust in more recent years from economic depression and a changing economy.

The Crossroads: In America, this is the area around the junction of the Ohio and Mississippi rivers, near St. Louis and Nashville, and into the Ozark Mountains in the west.  For Russia, this actually means Belarus, but also Smolensk and other parts of western Russia.  This is the area where cultures meet and clash, nestled between the American North and South, and between Russia and Europe, integrating and meshing opposing ideologies.

The Breadbasket: In America, this is the Great Plains and part of the Midwest, from North Dakota to Indianapolis to Oklahoma; and in Russia this means the Black Sea littoral and as far east as Orenburg.  The Breadbasket is exactly what it sounds like–the “fertile triangle” and source of food for a hungry nation.

The Old Mountains: In America, the Appalachians; in Russia, the Urals.  These mountain ranges define the boundary between the old homeland and the new areas of expansion, and reflect the first traversal point on the road to national expansion and manifest destiny toward the Pacific.

The Tropical South: In America, this is clearly the Deep South and South Florida, a land of palm trees, lazily hot weather, and sultry culture.  But in Russia, this means The Crimea, southern Moldova, and the northwest tips of the Caucasus–a region similar in climate and, as in America, a recent boom of luxury and wealth built by a “sun and sin” economy. 

Mexistan: This is the alien yet internal culture–a fusion of foreign and domestic.  In America, this is the Southwest; in Russia, Central Asia–lands conquered in foreign conflicts, generally far-removed from the ancestral homelands, and harboring a people different from those who founded the nations.

The Land Ocean: This is the vast peripheral expanse–in America, the West; in Russia, Siberia–that forms the backdrop for each nation’s plunge into manifest destiny toward the Pacific Ocean.  The Land Ocean is a region defined by frontier mythology and by the subjugation and elimination of its native peoples.

The Pacific Gateway: In America, this region stretches from San Francisco to Alaska.  In Russia, it surrounds the Sea of Okhotsk, from Vladivostok to Petropavlovsk to the Bering Sea, where America and Russia’s Pacific Gateway Regions meet.  This area is marked by its extreme distance from the national homeland, as well as by its similarly extreme geography of volcanoes, mountainous peaks, and lush forests.

The authors have made their entire book available online, including all the comparative regional analysis of history, peoples, and culture.  They also include maps of the regions within both Russia and the United States, showing how these regions transcend state or national borders as unique geographic identifiers.

Click here to see the book in its entirety.  Click here to see an index of the maps for America and Russia. 

The book concludes with a quote by Alexis de Tocqueville that I remember well from my college political philosophy courses–one of his more prescient quotes to be sure, but also one that strikes at the heart of two of the world’s great nations:

There are at the present time two great nations in the world which seem to tend toward the same end, although they started from different points: I allude to the Russians and Americans…their starting point is different, and their courses are not the same; yet each of them seems to be marked out by the will of Heaven to sway the destinies of half the globe.

Thanks to Claire for another great recommendation!

US Urban Area Influences

If you grew up in Bordentown, New Jersey, would you be more likely to say you were from “near New York” or “near Philly?”  How about if you grew up in Rensslaer, Indiana–would it be Indianapolis or Chicago?  And what about Blackwell, Oklahoma–would you be from Wichita or Tulsa?  The map above, developed by the CommonCensus project, tries to answer these questions by showing the “spheres of influence” of major American cities.

In a country as large as the United States, people use a great many ways to describe where they grew up. Sometimes they describe their region, like the Mid Atlantic, and sometimes they say a part of their state, like Southern California.  But particularly if they’re from a small town or a rural area, people often say the name of closest big city to where they grew up.  Sometimes the answer is obvious–if you’re from Weehawken, New Jersey, you’re from New York City as far as most Americans are concerned.  And if you’re from Orinda, California, you’re really from San Francisco.  But for more rural places, tucked between major urban areas, the borders can get a little more fuzzy.

For example, the map shows that people living as far north as the Oregon border identify San Francisco as their major city; but go just a few miles south of San Francisco and you’re clearly in San Jose territory.  Virginia and the Carolinas seem particularly divided.  People in central Maine generally listed Portland as their largest nearby city, but respondents from Portland itself more frequently chose to identify with Boston than with their own home town.  

Click here or on the picture above to open a large version of the map.  You can also click here to see regional maps of New York City and San Francisco.

Population density has little influence on the results: Montana has nine separate cities competing for influence throughout the state, from Spokane, Washington to Rapid City, South Dakota; but New York, with its much higher population and population density, shows itself to be divided among eight spheres of influence, in spite of the influence of the Big Apple.  On the other hand, you could drive from South Dakota to Arizona before you left Denver’s sphere of influence.

The map above was created using a public survey available on the CommonCensus website.  It asks respondents to fill out their street address, city, and state to compute exactly where they live.  The survey then asks them to give a name to their local community (i.e., their home town), their local area (i.e., the community of smaller towns they grew up in), and the name the largest nearby city that influences their lives.  The survey also asks for three broader geographic areas respondents identify with, like “the South,” “Appalachia,” or “Northern California.”  Using these answers, CommonCensus is building a map of how Americans use cities and regions to identify their homes, regardless of city limits or state boundaries.

CommonCensus claims to have received responses from nearly 50,000 people since the project began in late 2005. But high numbers of respondents don’t make the results scientific–the project also indicates that only 29.2% of cities have at least one contributor, meaning that many of the borders still have along way to go before the stabilize.

Minard on Immigration

What better way to start the week than with another map by Charles Joseph Minard?  Cartographers and students of graphic design generally idolize Minard for his ability to translate large and complicated data sets into easily understandable formats.  I have previously covered one of Minard’s other works, but this map is just as interesting and incorporates some of the same principles as his map of Napoleon’s invasion of Russia.

This map charts the numbers and destinations of emigrants from Europe, Africa, China, and South Asia for the year 1858.  Minard correlates the thickness of each line with the number of emigrants it represents, with one millimeter equalling 1,500 people.  He also overlays the exact number of emigrants (in thousands) over the lines themselves.  Minard carefully puts divergent lines together and pulls them apart to demonstrate the flow of immigration from major ports in Europe and Asia and toward different final destinations.  Finally, Minard also adds a color-coding system to further ease the identification of nationalities on the move, and places a legend in the top-right corner.  Click on here or on the picture above to open a large version of the picture.

Here is a translation of the title:

Rough and Figurative Map representative of the year 1858

The Emigrants of the World

The countries from where they depart and the ones where they arrive, drawn by Mr. Minard, Inspector General of Bridges and Roads in retirement, principally from the public records in “European Emigration” by Mr. A. Legoyt and the Merchant’s Magazine of New York.

Paris, 26 September 1862

And a translation of the legend:

Colors indicate the countries from where the Emigrants have left.

The numbers of Emigrants are represented by the width of the colored zones, with one millimeter representing fifteen hundred Emigrants; they are also expressed by the numbers written across the zones of which the unit is one thousand Emigrants.

Some aspects of the map jump out immediately: for instance, the outlines of the continents are fairly inaccurate–especially North America and Australia–and Europe is disproportionaly large.  But these inaccuracies don’t seem to diminish the impact of the map.

The top left quadrant is dominated by the large numbers of emigrants from Britain and Northern Europe.  But note that, according to Minard’s statistics, more Englishmen were emigrating to Australia than to the United States.  Also note the relatively small amount of French immigrants to America, especially compared to the large numbers from Northern Europe who faced similar language and cultural barriers.  There are small slivers of immigration from France, Northern Europe, and Britain to South America, and slightly more considerable numbers from France to its colony in Algeria.  The map also indicates that French immigrants to North America generally departed from Le Havre on the English Channel, whereas Frenchmen destined for South America left from Bayonne or Bordeaux.

The map also demonstrates the considerable flow of African labor to European colonies.  The thick lines from the Congo region to the Indian Ocean islands of Reunion, a French colony, and Mauritius, a British colony, represent the labor necessary to run the sugar plantations on those islands.  There are also thinner lines indicating African labor was still flowing to the Caribbean, to the French sugar islands of Guadeloupe and Martinique, and to the British territories of Jamaica, Trinidad and Tobago, and Guyana.  But as the map indicates, three times as many Africans were taken to Mauritius and Reunion as went to both the French and British territories in the Caribbean.  Note the lack of African labor traveling to the United States.  Although emancipation was still several years away in 1858, the U.S. Congress had banned the import of foreign slaves fifty years before, in 1808.

There are similar patterns in the immigration from South Asia.  Large numbers of laborers are shown leaving Madras and Calcutta for Mauritius and the Caribbean surgar islands.  Minard’s data indicates that although comparable numbers of people departed Madras and Calcutta for Mauritius, most of the laborers departing for the Caribbean departed from Calcutta, with only a tiny number leaving from Madras.

Finally, Minard illustrates three strands of Chinese emigration.  The first is to Australia, where it joins the large numbers of Britons arriving in Victoria.  The second is a thin line around the Cape of Good Hope and across the Atlantic to the Caribbean, mostly to Cuba, but with a tiny offshoot to Guadeloupe.  The third line disappears over the edge of the map into the Pacific ocean, toward distant California.

This map only represents one year of data, so multiply these statistics over several decades and it is obvious how North America in particular became a continent of immigrants.  The map is also designed well enough that, with the exception of knowing the subject of immigration, the data is generally understandable without needing to read the legend.

Notes: This map is based on the Library of Congress version accessible here.  I ran the picture through Photoshop to lighten it and make the colors a little brighter but I did not alter any of the components of the map itself.   And thanks to Mike for the translation!

The Phone and Internet Map of Global New York

Everyone knows New York is a cosmopolitan city, with hundreds of ethnicities from around the world clustered into a few small boroughs and the larger outlying suburbs.  Many maps have been made charting New York’s ethnic neighborhoods, but not until today have I seen any maps that chart the connections between those neighborhoods and the rest of the world.  Thankfully, a team from MIT has taken on the task and developed some informative and beautiful maps to show their research to the rest of us. 

Researchers at MIT’s senseable city laboratory, in collaboration with AT&T, created a set of wonderful maps illustrating New York City’s voice and Internet connections with the rest of the world. They called this project the New York Talk Exchange.  Three of these maps are available online at this website, but they are all available for viewing at the New York Museum of Modern Art (MoMA) exhibit Design and the Elastic Mind.  The exhibit runs through May 12, 2008, so hurry and see it before it closes if you can.

The first map, entitled Globe Encounters, tracks Internet protocol (IP) connections between New York and cities around the world.  In this map, the brighter a city’s glow, the more IP connections it has with New York, visually showing the strong New York business and personal connections to both Western Europe, Latin America, and the Caribbean.  East Asia and the Middle East, though not shown in the snapshot, also certainly have bright glows over their mahor cities.

The second map, Pulse of the Planet, “illustrates the volume of international calls between New York City and 255 countries over the twenty-four hours in a day.” The map exaggerates the size of countries based on the volume of calls they make and recieve, and highlights the top cities.  This snapshot shows spikes over Toronto, Montreal, London, and Tokyo.

Finally, the map entitled World Within New York breaks the boroughs down into square grids and, for each, shows the percentage of phone calls to different regions of the world.  This snapshot highlights a grid square over Flushing, Queens, showing strong connections to Korea, Portugal, Canada, China and Taiwan, and the Dominican Republic.

More information about these maps is available from the sensable city laboratory website, as well as from this article from MIT.  If anyone attends the MoMA show where these maps are displayed, let me know and I’ll post your reactions!

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