Effectively Market Your
Business Using Electronic Maps
Part 2. GIS TUTORIAL
James Pick
University of Redlands
4-15-07
Tutorial supported by U.S. SBA Grant No. SBAHQ-06-1-0046.
Outline
20 minutes
10 minutes
Introduction to GIS
Geographical basis, data, boundary files,
mapping, GIS software
An Example
15 minutes
Worksheet and Discussion
15 minutes
GIS analysis and modeling
Distance, proximity, buffers, thematic mapping.
location quotient
The range of techniques available
Introduction to GIS.
Geographical basis, data, boundary
files, map basics, GIS design elements
============================
Fundamental Definition of GIS
A GIS consists of the following elements:
• Data-base of attributes
• Spatial information
• Some way to link the two
Source: Clarke, 2003.
GIS as a Toolbox
• GIS can be viewed as a set of tools.
• Sometimes this is called a process
definition because the subtasks are
sequentially arranged.
• An example of using a set of tools as
procedures is
– Get addresses from a marketing list
– Geocode them (to get X—Y points)
– Map them
Example of Web-based application
– ordering pizza on-line
(Source: Pick, 2008)
GIS as an Information System
• GIS is a type of information system.
• Data for a GIS are stored in a data-base. They
are processed and output as maps and other
related outputs.
• Some definitions can go as far that GIS is a
spatially-enabled data-base.
• GIS can be used in collaboration with other
business systems such as accounting or
marketing.
• GIS has also be provided from the World Wide
Web as a Map Service. Google Maps is an
example.
GIS-Intensive Organizations
• GIS developed earlier and much more fully in
the public sector, while business uses are more
recent.
• In many city, county, and state agencies in the
U.S., such as country planning agencies, GIS
permeates the way people think and interact
with each other.
• In the business world, many large and mediumsized businesses have GIS systems.
• In some businesses, GIS permeates the
company, such as ESRI, Sears Roebuck, and
Rand McNally.
Impact of GIS on Organizations
• GIS changes job roles, alters teamwork, shifts crossfunctional information exchange, and changes
hierarchies.
• For example, historically companies that were mapintensive tended to have map rooms with skilled
personnel to produce, print, store, and revise maps.
• If modern GIS becomes pervasive, the preponderance of
these functions are done electronically, but some GIS
expertise is needed to set up, test, train, and maintain
the GIS applications.
• End users may also become proficient in GIS.
• In small business, GIS may be supported by one or two
people inside or outside the firm. Users in the firm will
be impacted by new capabilities intended to increase
their efficiency and productivity.
Elements of a GIS
• A GIS
– Accesses spatial boundaries and attribute
(i.e. non-spatial) data
– Analyzes the spatial and attribute data
• A GIS includes:
– A data-base
– Tools, algorithms, and models for manipulate
spatial data and attributes
Design Elements of a GIS
Figure 1.19. Design Elements of a GIS
Output
Analysis and Modeling
Attribute Tables
Map Layers
Attribute Input Data
Boundary File Input Data
(Source: Greene and Pick, 2005)
Map Layer
• A GIS might have a
single map layer, but
more commonly
include two or more
layers
Example of Processing with Simple
GIS
Figure 1.20 Example of Processing with a Simple GIS
Analysis of Intensity of Highways compared to population
density.
Spatial Modeling of Transportation grid inside and outside
of the city limits and its effect on gas taxes
Attribute Tables
Map Layers
Population
Number of City Employees
Gross City Revenue
Total Tax Revenues
City Limits
Highway Width
Highway Speed Limit
Vehicle Traffic Daily
Gas Stations on Highway
Highway Transportation Network
(Source: Greene and Pick, 2005)
Relationship of Spatial and
Attribute Data in Multiple GIS
Layers
Adapted from West, 2000.
Baseball example of non-spatial
versus spatial query.
Keith Clarke gives the example of baseball cards. If
we associate the X-Y coordinate location of the
stadium that the player is associated with, we are
adding a spatial attribute.
•Example of query without the spatial attribute. “Find
all players with a batting average over .300.
•Example of query with the spatial attribute. “Find all
players with a batting average over .250 and whose
location is within 300 miles of Yankee Stadium.”
Geographic Location
• How is geographic location determined.
Often by latitude and longitude.
• It can be by more advanced coordinate
systems, such as 3-D, but lat-long will do
for now.
Coordinate System – Lat, Long
• Locations are represented in a GIS with
the use of X and Y coordinates, which
represent real-world coordinates (in 3
dimensions) that have been projected onto
a two dimensional surface.
• The geographic grid of latitude and
longitude is a commonly used geographic
reference system.
• It is not a true coordinate system, however
because it measures angles from the
center of the earth in degrees, minutes,
and seconds rather than distances on the
earth's surface.
Latitude
The latitude angle
lambda
“Imagine the Earth was a transparent sphere
Its middle point is O, the center of the Earth. To
specify the latitude of some point P on the
surface, draw the radius OP to that point. Then
the elevation angle of that point above the
equator is its latitude λ--northern latitude if
north of the equator, southern (or negative)
latitude if south of it.”
Source: NASA, 2006.
Longitude
”What that value is depends of course on
where we begin to count--on where zero
longitude is. For historical reasons, the
meridian passing the old Royal Astronomical
Observatory in Greenwich, England, is the one
chosen as zero longitude. Located at the
eastern edge of London, the British capital, the
observatory is now a public museum and a
brass band stretching across its yard marks
the ‘prime meridian.’”
Source: NASA, 2006.
Geographic Information
• A map stored inside a GIS is described by
coordinates.
• A sophisticated map contains a huge
number of coordinates. This is possible
because of the huge gains in storage
described in the introductory lecture.
Map Scale and Zooming
• Maps reduce the size of the earth.
• Map at 1:1 scale means 1 foot on the map is the
same as 1 foot on the earth. It would be a lifesized drawing.
• 1:500 scale means that 1 foot on the map is the
same as 500 feet on the earth.
• An idea of scale is that 1:40,000,000 implies that
the circumference of the earth at the equator
would map to the size of a postage stamp.
• U.S. – most important scales at 1:100,000 and
1:24,000 (USGS maps). Also 1:50,000 is
important.
• In GIS software it is easy to shift between
scales, a feature known as Zooming.
GIS Structures – Features and
Feature Properties
• GIS structures are put together from points, lines, and
areas (polygons).
Points – the basic coordinate location – zero dimensional
Lines – connected together by two points – one
dimensional.
Areas (also called polygons) bounded by three or more
points connected by lines – two dimensional.
Points, lines, and areas are features. They are further
defined by feature properties of size, distribution,
neighborhood, shape, pattern, contiguity, shape, and
orientation.
(Source: Pick, 2008)
Points, Lines, and Polygons
Source: Clarke, 2003.
Summary on Geographic Roots of GIS
• A GIS is defined by location, data, and the
relationships between them.
• Attribute data are stored in relational
tables
• Locations are stored in map layers.
• Data and map layers are related together.
Summary on Geographic Roots of GIS
• Coordinate systems determine the X-Y
locations of points. “X” and “Y” are
defined differently in different coordinate
systems. The best known is latitude and
longitude.
• Map scale relates the area on the map to
the area on the earth.
• Points, lines, and areas (polygons) are the
spatial features that all maps are
composed of. Labels are attached to
points.
Design Elements of a GIS
Figure 1.19. Design Elements of a GIS
Output
Analysis and Modeling
Attribute Tables
Map Layers
Attribute Input Data
Boundary File Input Data
(Source: Greene and Pick, 2005)
GIS Capabilities
• GIS can enhance what is normally in
tables and add many new insights.
• For instance, if a small business’s 500
customers are shown in a table, it is hard if
not impossible to determine their locational
patterns.
• GIS can show the locations.
• Further, it an analyze their relationships
and trends.
Map Layer
• A GIS might have a
single map layer, but
more commonly
include two or more
layers
Addresses of business clients, converted to points.
% of Customers By Distance
Sometimes the greatest
value comes from simply
looking at your data from
a different perspective!
30
25
20
15
10
5
0
1
2
3
4
5
6
Distance (Miles)
•Over 50% of customers
live within 2 miles
•Over 80% of customers
live within 4 miles
7
8
9
Retail/Site Selection/Marketing
Site Selection
•Find best locations for new stores
•Identify inefficient stores
•Trade Areas
•Market Penetration
•Market Share
Target Marketing
•Understand customer demographics
•Identify untapped enclaves of future
customers
•Direct Mailings
Example – Workforce for Industrial Siting
- Using the Location Quotient (LQ)
LQ = (Eij/Ej)/(Ei/Et) * 100.
Where Eij = Employment in sub-area j in sector i;
Ej = Total employment in sub-area j;
Ei = County employment in sector i;
Et = Total County employment.
A location quotient greater than 100 indicates specialization in the
category, and less than 100 indicates that the ZIP Code is not
specialized in that category.
(Source: Greene and Stager, 2005)
Location Quotient
Example
ZIP Code A has 350 workers in the bottling industry out of
a total labor force of 1,000, while in the county containing
ZIP Code A, there are 50,000 workers in the bottling
industry and a one million labor force total. The location
quotient is calculated as follows:
LQ = (EZIP/LFZIP) / (ECOUNTY/LFCOUNTY) * 100 =
(350/1,000) / (50,000/1,000,000) * 100 = 700
Zip Code A is then said to be specialized in the bottling
industry because the location quotient is greater than 100.
In the Los Angeles County GIS, the sub-areas are zip codes
while the larger area is Los Angeles County.
Location Quotients for Manufacturing and
Professional Employment, Los Angeles, 2000
(Source:
Greene and
Stager, 2005)
Comparison of Professional Employment
to the corridor of Wilshire Blvd.
Location Quotient
of Professional
Employment for
same area
( Source: Greene and Pick, 2005).
LQs for Nine Employment Sectors, LA
(Source:
Greene and
Stager, 2005)
Worksheet and Discussion
GIS Analysis and Modeling
•
•
•
•
•
•
•
Descriptive methods
Buffer analysis
Map overlays
Proximity analysis
Change detection
Modeling and forecasting
Statistical analysis
(Source: Pick, 2008)
The spatial relationships lead to the
following fundamental questions
(1) How can two maps be compared with
each other?
(2) How can variations in geographic
properties over a single area or GIS data
set be described and analyzed?
(3) How can we use what we have learned
in the analysis to explain and predict
future maps of the geography in
question?
Map Overlay Example
Input - census blocks
Overlay - store trade areas
Result of union
(Source: Greene and Stager, 2005)
Overlaying map layers:
This example has layers for city boundaries,
transportation, land use, and business locations.
Buffer Analysis
• In buffering, GIS software forms bands on
either side of a points, line, or polygon to
perform analysis within the bands.
• Simple example: to assign half-mile
buffers on both sides of highway, and ask
how many service stations are within the
buffer
Example of
Spatial
Change.
Change in
population
densities in
Chicago, 19402000
Source: Greene and Pick, 2006
Proximity Analysis
• It assesses how close certain map objects
are to other map objects.
• For example, it can determine how close
the population residing in a census tract is
to a competing set of grocery stores.
Understanding the demographics of your market area.
Handheld GPS Unit Showing
Redlands Streets and Businesses
(Source: Pick, 2008)
Conclusion
• GIS can be used to analyze small business problems
• Customer mapping can reveal trends important to
business planning and profits.
• Overlays can increase the information available.
• Time sequences can show changes in business
activities and markets over time.
• Spatial analysis can lead to better targeting of
customers, facilities, workers, and other business
entities.
• GIS is a technology to make more data more usable and
put it to greater use for efficiencies, better performance,
and profits.