GIS and Critical Thinking: The Role of Spatial Concepts

Michael F. Goodchild

University of California

Santa Barbara

Geographic information science• The science behind the systems• The systematic study of the nature of geographic

information• The set of disciplines that study geographic

information– cartography, surveying, photogrammetry, geodesy– computer science, cognitive psychology, operations

research, economics, …

• The set of issues that arise during use of GIS– that are prompted by GIS– what GIS users think about– what makes spatial special

A spatial turn in science• Adding space to theory

– the New Economic Geography• space impeding flows of information, operation of markets• transport costs

– Spatial Ecology• a heterogeneous resource base• space impeding interactions, breeding• metapopulations

• Reasoning from spatial data– cross-sectional– new tools to overcome methodological problems– impacts in all social, environmental disciplines

A growing literatureSpatially Integrated Social Science (Goodchild and Janelle, OUP, 2004)

The drivers• New technologies, new data

– geographic information systems (GIS)– remote sensing– positioning (GPS)– using location to integrate– providing spatial context– delivery mechanisms

• Applications of science in policy, decision making, design

the natural, social world

abstracted knowledge

nomothetic science

planning, decision making

What fundamental concepts?

• How do people organize knowledge about space?

• How should we organize the tools?• What does it mean to think spatially?

– are people who do fundamentally different?– can one train to be a spatial thinker?– would you know one if you met one?

Spatial thinking• Larger than GIS

– compare GIScience

• What every Google Earth user needs to know

• One of Gardner’s seven types of intelligence

“1. Linguistic Children with this kind of intelligence enjoy writing, reading, telling stories or doing crossword puzzles.

2. Logical-Mathematical Children with lots of logical intelligence are interested in patterns, categories and relationships. They are drawn to arithmetic problems, strategy games and experiments.

3. Bodily-Kinesthetic These kids process knowledge through bodily sensations. They are often athletic, dancers or good at crafts such as sewing or woodworking.

4. Spatial These children think in images and pictures. They may be fascinated with mazes or jigsaw puzzles, or spend free time drawing, building with Lego or daydreaming.

5. Musical Musical children are always singing or drumming to themselves. They are usually quite aware of sounds others may miss. These kids are often discriminating listeners.

6. Interpersonal Children who are leaders among their peers, who are good at communicating and who seem to understand others' feelings and motives possess interpersonal intelligence.

7. Intrapersonal These children may be shy. They are very aware of their own feelings and are self-motivated.”

Howard Gardner

http://www.professorlamp.com/ed/TAG/7_Intelligences.html

What is spatial thinking?

“Three aspects of spatial ability:• Spatial knowledge

– symmetry, orientation, scale, distance decay, etc.

• Spatial ways of thinking and acting– using diagramming or graphing, recognizing

patterns in data, change over space from change over time, etc.

• Spatial capabilities– ability to use tools and technologies such as

spreadsheet, graphical, statistical, and GIS software to analyze spatial data”

http://www.nap.edu/catalog/11019.html

“Spatial thinking tasks• Extracting spatial structures (encoding)

– perception and creation of representation– show the spatial or conceptual relationships between

elements with respect to reference frame

• Performing spatial transformations• Drawing functional inferences

– complex spatial reasoning– combining representations and transformations to evaluate

or predict situations or events”

“The spatially literate student• Knows where, when, how, and why to think

spatially• Practices spatial thinking with

– broad and deep knowledge of spatial concepts and representations

– well-developed spatial capabilities for using supporting tools and technologies

• Adopts a critical stance to spatial thinking– can evaluate the quality of spatial data based on source,

likely accuracy, reliability– can use spatial data to construct, articulate, and defend

a line of reasoning in solving problems and answering questions”

Thinking about space• Wayfinding skills

– mental maps

• Three levels of knowledge– landmark– route– survey

Landmark knowledge

• Geography as a list of places– no spatial relationships

• no adjacency• "if this is Tuesday it must be Belgium“• which two pairs of US states are adjacent both in space

and in alphabetical order?

– no spatial context• "how long is this flight?"

– no knowledge of intervening places

Tract

1

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4

5

6

7

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Pop

2966

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4983

4130

3229

4086

3979

3786

Location

x,y

x,y

x,y

x,y

x,y

x,y

x,y

x,y

Shape

What value is location as an explanatory variable?

Route knowledge• Sequences of intervening places

– no ability to short-cut– no directions, distances– context along the route– distorted context off the route

http://www-personal.umich.edu/~mejn/election/

Michael Gastner, Cosma Shalizi, and Mark NewmanUniversity of Michigan

Survey knowledge• Full two-dimensional representation

– distances– orientations– shortcuts– context

• vertical and horizontal

Metric space

List of places

Attribute table

Linear network

Point, extended features and attributes

Adjacency matrix

W matrix of proximities

Non-metric spaces

Cartograms

Developing intelligences• Mathematical, verbal, musical

– attention throughout K-16

• Spatial– IQ tests– trivia questions

Which is further west, San Diego or Reno?

Naïve geography• Popular misconceptions• Can a GIS be built to honor popular

misconceptions?– direct people to drive north from LA to Santa

Barbara– no, because such a GIS would violate the basic

principles of geometry

What fundamental concepts exist in spatial intelligence?

• Are they sophisticated and abstract enough to warrant a place in the curriculum?– like mathematics, statistics, language, music– can spatial intelligence gain more respect?

• Are they an appropriate basis for improved GIS user interface design?– does the interface need improvement?

A complex set of tools• A GIS is capable of virtually any conceivable

operation on spatial data– how many conceivable operations are there?

• ArcGIS 9.2 toolkit– 510 operations– 10 headings, up to 4 levels of hierarchical organization– headings include:

• Analysis, Spatial Analyst, 3D Analyst, Geostatistical Analyst, Spatial Statistics

• Data Management, Conversion

• Under which heading would you find the routine to convert a shapefile to KML?

Map algebra• Local, focal, zonal, global

– raster only– is there something equivalent for vector?

• van Duersen’s scripting language– c = a + b

• Andy Mitchell’s books– ESRI Press

Volume 1:

Mapping where things are

Mapping the most and least

Mapping density

Finding what’s inside

Finding what’s nearby

Mapping what’s changed

Volume 2:

Calculating the center, dispersion, and trend

Identifying patterns

Identifying clusters

Analyzing geographic relationships

!

Snow, J. (1949) Snow on Cholera.

Oxford University Press.

from Lance Waller, Emory University

Johnson, S. (2006) The Ghost Map. Riverhead

1. Google Earth image

2. 1843 map of London from David Rumsey collection

3. Pump and death locations from my own web site

popvssoda.com

1. Location• Defining and measuring location

– the impossibility of exact measurement

• From infinitesimal point to extended area• Place

– how many places are there in the U.S.?– what is the most populous city in the world?

• Location as context• Location as common key

– mashups

• It is important to know where events occur

fundrace.huffingtonpost.com

2. Distance, direction• Measurement

– plane, globe– buffers

• Distance decay– decline of interaction with distance– cost, time impediments– footprints of human behavior

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3. Neighborhood/region/territory

• The context of individuals– action space

• Homogeneous areas• The reporting zone containing the individual

– arbitrarily imposed on a continuous Earth

• The ecological fallacy– the modifiable areal unit problem

• Competition for space– trade areas, bird territories– functional regions

4. Scale• Level of detail

– the inevitability of generalization

• Extent– generalizability of results

• Methods of upscaling, downscaling• Fractal concepts• Scale is always important

– many properties cannot be defined independently of scale• length of a coastline

• slope of a topographic surface

• land use class

Unique to spatial thinking?• Analogs of spatial scale in other domains• Observed properties of spatial data

– what makes spatial special?

5. Spatial dependence• “All things are related, but nearby things are more

related than distant things”– W.R. Tobler, 1970. A computer movie simulating urban

growth in the Detroit region. Economic Geography 46: 234-240

– “nearby things are more similar than distant things”– geostatistics, Moran statistic– the most important property of any spatially distributed

phenomenon

• Challenges the normal assumptions of statistical tests– independent, randomly chosen samples

Source: Mason et al., Atlas of Cancer Mortality for U.S. Counties, NCI, 1975

www.csiss.org

6. Spatial heterogeneity

• TFL describes a second-order effect– properties of places taken two at a time– a law of spatial dependence– is there a law of places taken one at a time?

• Spatial heterogeneity– non-stationarity– uncontrolled variance

Practical implications• A state is not a sample of the nation

– a country is not a sample of the world

• Results of any analysis will depend explicitly on spatial bounds

• Classification schemes will differ when devised by local jurisdictions

• Figures of the Earth will differ when devised by local surveying agencies

• Global standards will always compete with local standards

• Strong argument for place-based analysis, local statistics, geographically weighted regression

Summary• Working with spatial data is not always

simple and intuitive– but it can yield great insights if handled

appropriately

• There is a substantial body of knowledge that needs to be acquired by anyone working with spatial data– you would never think of doing a t test without

taking a course in statistics– why would you consider using a GIS without

taking a course in spatial thinking?

Other spaces

the human brain

molecular chemistry

the cosmos

nanoscience

UCSB is spatial

• Exchange ideas and resources• Promote new tools, research, and

applications• Enhance spatial literacy • Community of spatial thinkers

• Web portal on spatial UCSB• Seminars and workshops• Spatial help desk• General course(s) on spatial

thinking

Visualization

Analysis

Representation

Simulation Modeling

CognitionPerception

Application

Space-time

Patterns &

Processes

Computation

Humanities Fine Arts Engineering

Social Sciences Physical & Bio Sciences

Information-technology Integration

EducationManagement

Planning& Policy

Conclusions• It is possible to enumerate the fundamental

concepts of a spatial approach– six broadly defined concepts– 27 in recent publication– De Smith, Goodchild, and Longley (2006)

Geospatial Analysis– www.spatialanalysisonline.com

• These concepts are what we employ when we think critically about spatial data

Conclusions (2)• This is more than GIS

– an enveloping conceptual framework for many new technologies

– many drivers

• One of a minimal set of intelligences– part of everyone’s education