How long will it take to describe all that you can see in...

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“The world is complex, dynamic, multidimensional; the paper is static, flat. How are we to represent the rich visual world of pexperience and measurement on mere flatland?”(Tufte, 1990 p.9)

We must create a new language, consider a transitorystate of new illusions and layers of validity and accept the possibility that there may be no language to describe ultimate reality, beyond the language of visions.

(Denes A. 1979, p.3)

How long will it take to describe all that you can see in words?

Conventional mappingConventional mapping

The Mercator projectionThe Mercator projection“A Mercator projection is a

mathematical method of showing a map of the globe on a flat surface. This projection wasThis projection was developed in 1568 by Gerhardus Mercator a Fl i h hFlemish geographer, mathematician, and cartographer”

See http://science.nasa.gov/Realtime/rocket_sci/orbmech/mercator.htmlfor more details

Mercator projection of the Earth. Source image is from NASA's Earth Observatory "Blue Marble" series. Taken from: http://en.wikipedia.org/wiki/File:Mercator-projection.jpg

Tissot´s Indicatrixs by Mercator-Projectionhttp://en.wikipedia.org/wiki/File:Tissot_mercator.png

Land areaLand area

Source: Hennig, 2009; http://benhennig.postgrad.shef.ac.uk/http://news.bbc.co.uk/1/hi/in_pictures/8284655.stm

But conventional mapsBut conventional maps• cannot show how many people live in small areas – instead y p p

they show how little land supports so many people• cannot show who the people are, what they do, where they

go…• They will not show the distributions of people changing —

international migration, moving house, or just going to work. te at o a g at o , ov g ouse, o just go g to wo .• They cannot portray the distribution of the wealthy or the

poor; on the map, at almost any scale, they live in much the i h f N ill h h h dsame square inch of paper. Nor will they show where and

when people had certain jobs, certain power, voted, were out of work, lived and died.

What is a cartogram?What is a cartogram?"Erwin Raisz called cartograms 'diagrammatic maps.' Today they might be

ll d t l b h t d i i lcalled cartograms, value-by-area maps, anamorphated images or simply spatial transformations. Whatever their name, cartograms are unique representations of geographical space. Examined more closely, the value-by-area mapping technique encodes the mapped data in a simple and by a ea app g tec que e codes t e apped data a s p e a defficient manner with no data generalization or loss of detail. Two forms, contiguous and non-contiguous, have become popular. Mapping requirements include the preservation of shape, orientation contiguity, and data that have suitable variation Successful communicationand data that have suitable variation. Successful communication depends on how well the map reader recognizes the shapes of the internal enumeration units, the accuracy of estimating these areas, and effective legend design. Complex forms include the two-variable map. g g p pCartogram construction may be by manual or computer means. In either method, a careful examination of the logic behind the use of the cartogram must first be undertaken.“

Dent, 1996, my emphasisafter http://www.ncgia.ucsb.edu/projects/Cartogram_Central/types.html

Homunculus

Source: http://en.wikipedia.org/wiki/Homunculus

0% 10% 20% 30%

Population

0% 10% 20% 30%

Japan

Western Europep

North America

Eastern Europe

South AmericaSouth America

Greater China

Near East

Far East

Greater India

Northern Africa

Southeastern Africa

Central Africa

0% 10% 20% 30%

Population

0% 10% 20% 30%

Japan

Western EuropeThis too is a population

t f th ldp

North America

Eastern Europe

South America

cartogram of the world

– simply a very basic and non-continuous South America

Greater China

Near East

cartogram.

= Middle East= Eastern Asia

Far East

Greater India

Northern Africa

= Asia Pacific= Southern Asia

Southeastern Africa

Central Africa

Land Area

85

75

80

85

65

70

75

y (y

ears

)

55

60

Expe

ctan

cy

45

50 Life

35

40

85

75

80

85

65

70

75

y (y

ears

)

World average = 67 years

55

60

Expe

ctan

cyWorld average 67 years

45

50 Life

35

40

50

35

40

45

0 (%

)

25

30

35

until

age

40

15

20

25

surv

ing

u

5

10 Not

0

50

35

40

45

0 (%

)

25

30

35

until

age

40

15

20

25

surv

ing

u

World average = 14%

5

10 Not

0

3500

4000

r)

2500

3000

erso

n/ye

ar

2000

2500

heal

th ($

/p

1000

1500

endi

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0

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Spe

0

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4000

r)

2500

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erso

n/ye

ar

2000

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heal

th ($

/p

1000

1500

endi

ng o

n h

World average = $600 per person per year (PPP$)

0

500

SpeWorld average $600 per person per year (PPP$)

0

Automated computer algorithmsAutomated computer algorithms• Develop a method which is as simple and easy to p p y

understand and implement as possible• Generate “readable” maps by minimizing the distortion of

th h f th hi l b i dthe shape of the geographical areas being mapped, while at the same time preserving accuracy and maintain topological features.

• Determine the cartogram projection uniquely• Minimize computational speed• Make the end result independent of the initial projection

being used• Make the end result look aesthetically acceptable• Make the end result look aesthetically acceptable• Have no overlapping regions

One small step for two men, i l f ione giant leap for mapping

In 2004 there was a human cartogram breakthrough with the creation of a new density-equalizing map projection by Michael Gastner and Mark Newman of the Universityby Michael Gastner and Mark Newman of the University of Michigan, USA. Perhaps what they have achieved is potentially the most significant breakthrough in cartography since Gerardus Mercator’s wall maps ofcartography since Gerardus Mercator s wall maps of 1569! Gastner and Newman have made their projection widely available – but will it be widely used?

Gastner and Newman exampleGastner and Newman example

Th di t ib ti fThe distribution of news stories in the United States.

(a) Conventional map of the states.

(b) “Mindshare map” in(b) “Mindshare map” in which the sizes of states are proportional to the p pfrequency of their appearance in news stories.

Land AreaLand Area

Population year 0Population year 0

Population year 1500Population year 1500

Population year 1900Population year 1900

Population year 1960Population year 1960

Population year 2002Population year 2002

Births 2002Births 2002

HIV/AIDS 2002HIV/AIDS 2002

Toys Imported ($)Toys Imported ($)

Sewerage connectedSewerage connected

Containers loadedContainers loaded

Crude exportedCrude exported

ChildrenChildren

ElderlyElderly

LandLand

Happy23 - 3940 - 5455 - 7172 - 105106 - 224

Unhappy.shp22 - 2425 - 4445 - 6465 - 107108 - 201

Ballas and Dorling, 2009

Greater London parliamentary constituencies

Ballas and Dorling, 2009

“Core Poor” cartogram of Greater London parliamentary constituencies

Ballas and Dorling, 2009

“Exclusive Wealthy” cartogram of Greater London parliamentary constituencies

Ballas and Dorling, 2009

SummarySummary• Conventional maps that show how cities, regionsConventional maps that show how cities, regions

and countries appear from space, are not an appropriate way to show the spatial distributions of humans and their characteristics!

• Human cartography provides the appropriate methods and tools for the depiction of the spatial distribution of variables pertaining to human societies rather than environmental geologicalsocieties rather than environmental, geological or meteorological problems

• Future directions: mapping flows animation• Future directions: mapping flows, animation, google earth

Software and Electronic ResourcesSoftware and Electronic Resources

• ScapetoadScapetoadhttp://scapetoad.choros.ch• Cartogram Generator• Cartogram Generatorhttp://people.cas.sc.edu/hardistf/cartograms/

W ld• Worldmapperhttp://www.sasi.group.shef.ac.uk/worldmapper/• People-powered mapshttp://news.bbc.co.uk/1/hi/magazine/8280657.stm