Transcript What is GIS?

An introduction to GIS for
NOF projects
Paul Miller
Interoperability Focus
UKOLN
[email protected]
http://www.ukoln.ac.uk/
UKOLN is funded by Resource: the Council for Museums, Archives and Libraries,
the Joint Information Systems Committee (JISC) of the Further and Higher
Education Funding Councils, as well as by project funding from JISC and the EU.
UKOLN also receives support from the Universities of Bath and Hull where staff
are
1 based.
What is GIS?
“A system for capturing,
storing, checking,
integrating,
manipulating, analysing
and displaying data
which are spatially
referenced to the Earth.”
(AGI, 1995)
2
See citymap.cityofsydney.nsw.gov.au/
3
What is GIS?
Geographic Information System
• Geographic
• Over 80% of public sector data is said to have a
geospatial component
– An address, a postcode, a grid reference, even a
county…
• Information
• Much of the data stored in databases can be
linked using this geospatial component
– Salary, buying preferences, artistic style,
historical period, photographer…
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What is GIS?
Geographic Information System
• System
• Not simply the output (often a map)
– Includes the processes, procedures, rules,
etc. to create, combine, validate, and
analyse data… .
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Do I need GIS?
• It depends…
• Do you have much data that would make
sense linked to a map?
– And do any licensing restrictions apply?
• Do you have access to the requisite skills
and equipment?
– The software is getting much easier, but it’s still
a complex area
• Does it fit with your project?
– Some projects really don’t need this… .
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Ways to use GIS (roughly)
• Behind the scenes, simply helping you
• Behind the scenes, producing map images
• Behind the scenes, producing map images to
drive an image map
• On the website, selecting data in response to
user queries
• On the website, producing maps in response to
user queries
• On the website, producing maps in response to
user queries, and allowing the user to interact
with the result.
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Ways to use GIS
• Simply helping you…
• Plotting locations of buildings photographed
for management reasons?
• Ensuring equitable distribution of funds by
geography?
• Tracking users against known areas of
Social Exclusion?
• Highlighting significant areas for more work?
• The user may never know
• ‘Boring’
• Useful.
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Ways to use GIS
• Producing map images…
• Combining different sources of data in
order to produce maps, graphs, etc,
which illustrate points on your web
site.
• These maps are ‘static’; just as if they
were printed in a book.
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10
See www.esri.com/mapmuseum/
Ways to use GIS
• Driving an image map…
• Combining different sources of data in
order to produce maps for your web
site.
• These maps are used as the basis of
‘image maps’
– Images on the web site that users click on
in order to select an area of interest
– Much simpler than building a GIS on the
Web, if this is the only functionality you
want to provide.
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See ads.ahds.ac.uk/catalogue/
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Ways to use GIS
• Selecting data in response to
user queries…
• You may want to allow searches of
your database using addresses,
locations, etc., but return information
without showing the user a map.
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See www.filmunlimited.co.uk/
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Ways to use GIS
• Producing maps in response to
user queries
• Perhaps the best–known of the web–
based GIS applications, and now
widely available.
• Services often offered by companies
who are prepared to integrate their
products with your web site, so that
you don’t need all of the expertise in–
house.
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See uk.multimap.com/
16
See uk.multimap.com/
17
See uk.multimap.com/
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See uk.multimap.com/
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Ways to use GIS
• Producing maps with which the
user can interact
• A ‘real’ Web GIS, likely to require the
greatest infrastructure, the most
powerful hardware and software, and
the most expensive licensing costs for
copyrighted data.
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See www.nationalatlas.gov/
21
See www.nationalatlas.gov/
22
See www.nationalatlas.gov/
23
See www.nationalatlas.gov/
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Issues to consider: Software
• Do you already have access?
• If you’re a Local Authority, try your Planning
Department
– But have a good idea what you want to do
• If you’re in Higher Education, try the
Geography Department or your Computing
Service
– Some GIS software is covered by a ‘CHEST deal’
• Do you have access to the skills?
• Maybe visit GIS 2001, or a similar
event?
• 18–20 September, Earl’s Court.
See www.iebusiness-forums.com/gis/
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Issues to consider: Software
• Look for standards compliance
• NOF Technical Guidelines
– www.peoplesnetwork.gov.uk/nof/
technicalstandards.html
• Open GIS Consortium
– www.opengis.org/techno/
specs.htm.
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Issues to consider: Data
• Do you have the data already?
• And if so, does your license allow you to use
it as you want to in this project?
• If you don’t have the data, how are you
going to get it?
• Buy from Ordnance Survey, Bartholomew,
Cities Revealed, etc?
– But remember to negotiate a license that lets you
do what you want to
• Digitise from paper originals?
– But remember to clear the rights for material that is
still in copyright.
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Issues to consider: Data
• Are you combining data sources?
• Scale
– Add the roads from a 1:250,000 UK road atlas to buildings from
a 1:1,250 urban map, and the results will be very poor
• Data granularity
– If you’ve gathered data on postal area (YO, G, etc.), there’s no
point plotting it on a map of postal districts (YO4, G67, etc.)
• Spurious accuracy
– “x lies within 100m of y”
– But x and y are drawn from data sources that are only precise
to within 50m
– So x and y might be adjacent, or they might be 200m apart.
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Remember…
Just because you have access to “a
GIS” or a map of your area…
• not all software or data can do
everything you want to it do
• and even if it can, your license might
not let you.
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Sources of guidance…
30
See http://ads.ahds.ac.uk/project/goodguides/gis/
31
See www.ordsvy.gov.uk/gis-files/
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Some pointers…
• ADS GIS Guide to Good Practice
• ads.ahds.ac.uk/project/goodguides/gis/
• Association for Geographic Information (AGI)
• www.agi.org.uk/
• National Geospatial Data Framework (NGDF)
• www.ngdf.org.uk/
• Open GIS Consortium (OGC)
• www.opengis.org/
• Ordnance Survey (OS)
• www.ordsvy.gov.uk/
• Web–Mapper
• www.web-mapper.com/
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