What is a GIS?

Objectives of PART 2:

1. Definitions in general (how they work)
2. Definitions of GIS
3. What makes GIS different?

<see also supporting resources for this lecture>

Definitions: how do they work?

• Formal definitions: produced by committees of experts, due deliberation
  • Examples:
    Académie Française: 40 "Immortals" sitting in funny hats deciding what is proper French <for obvious reasons, this website is in French...>
    Biology: International process to recognize a species of plants or animals <see resources>
  • Results of formal process often ignored (experts not powerful enough)
  • Depends on a division between the sign and the signified (words independent of objects)
• Alternative: totally individual... "When I use a word, it means what I choose it to mean - neither more nor less." (Humpty Dumpty in Lewis Caroll's Alice in Wonderland [Dodgson was a mathematician (and logician), and thus used to working with arbitrary symbolic definitions...]
• Historical process (a compromise): meaning shifts through use in changing circumstances; some kind of community required
  Words change through use and words influence the way things are seen... English Language dictionaries (like the Oxford English Dictionary) simply show the evolution of words; they work by "historic principles".
  

Defining GIS: different perspectives

• Purpose (why build a GIS)
• Capabilities (what it does)
• Process (How it does it)
• Who does it (Organizational/Institutional/skills required)

GIS: a buzz-word, a movement out of control of the originators.

Hence, the attempts at formal definition will not succeed.

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GIS definitions (some examples):

< more on Resources page>

An accepted (bland) definition:

"A system of hardware, software, data, people, organizations and institutional arrangements for collecting, storing, analyzing, and disseminating information about areas of the earth." (Dueker & Kjerne, 1989)

US Geological Survey's definition; note the links (originally a GIS poster) for integration and What's special
ESRI (they tried to hide it, but it was still there in their glossary)
www.gis.com (a front for ESRI) has a folksy definition focused on the toolkit and one tool in particular... and a HUGE slide show, quite revealing

<for more definition examples, see Resources>

An attempt to change the subject:

Geographic Information Science

GIS ... has done much to remove the traditional isolation between photogrammetry, remote sensing, geodesy, cartography, surveying, and geography (one could add to this list computer science, operations research, spatial statistics, cognitive science, behavioral psychology, and any other discipline with interests in the generic issues of spatial data). In an earlier paper, I argued that these were the disciplines of geographic information science, and that it made more sense for the research community to decode the GIS acronym in this way, focusing on the generic issues of spatial data, rather than on the limited solutions offered by today's geographic information system products. (Goodchild 1995, p. 42 emphasis in original)

Forer and Unwin (1998) have recently proposed "Geographic Information Studies" as a means to treat "the considerable social, legal and ethical issues".

Try as they might, GIS still stands for Systems.
"Just a tool", or a way of life - a different way of looking at the world?

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A working definition for the purposes of this course:

From Exploring GIS page 13

GIS: The organized activity by which people

• measure aspects of geographic phenomena and processes;
• represent these measurements, usually in the form of a computer database, to emphasize spatial themes, entities, and relationships;
• operate upon these representations to produce more measurements and to discover new relationships by integrating disparate sources; and
• transform these representations to conform to other frameworks of entities and relationships.

These activities reflect the larger context (institutions and cultures) in which these people carry out their work. In turn, the GIS may influence these structures.

An alternate short form:

Geographic Information System (GIS): Organized activity by which people measure and represent geographic phenomena then transform these representations into other forms while interacting with social structures.

This definition is derived from the ring diagram [concentric concerns of this course].

Differentiating GIS from other Information Technology

A definition can be used to exclude others, to establish firm barriers to entry, to accentuate differences... Definitions are connected to the practice of power. In the early period, it is important to establish what is a "real" GIS, contrasting with other kinds of IS.

• Computer Mapping (visual result, not analytical)
• CAD (finer scale, built-environment mostly; construction drawings, not 'maps')
• Database Management Systems (no spatial capabilities)
• Spreadsheets (all kinds of limits)
• Mailing Lists (how would you tell?)

Summary:

What have you learned?

• How 460 is organized
• How this organization follows an interpretation of how a GIS operates