1. Workshop on GIS Modeling (Part 1)
Grid-based Map Analysis and GIS Modeling Understanding Spatial Patterns and Relationships
Intermediate Workshop
Presented by Joseph K. Berry
“Map Analysis and GIS Modeling is technical Oz …you’re hit with a tornado of new concepts, then come back to yourself a short time later wondering what on earth all those crazy things meant”
Part 1 – Introduction and Data Considerations
Part 2 – Spatial Analysis Techniques and Considerations
Part 3 – Spatial Statistics Techniques and Considerations
Part 4 – GIS Modeling Approaches and Considerations
Berry & Associates // Spatial Information Systems S. College Ave, Suite 300, Fort Collins, CO Phone: (970) …visit our Website at
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

2. (Nanotechnology) Geotechnology (Biotechnology)
Workshop on GIS Modeling (Part 1)
(Nanotechnology) Geotechnology (Biotechnology)
Geotechnology is one of the three "mega technologies" for the 21st century and promises to forever change how we conceptualize, utilize and visualize spatial information in research, education and commercial applications
Global Positioning
System
Remote Sensing
Geographic Information
Systems
GPS/GIS/RS
Today’s Focus
Where is What
 Why and So What
Mapping involves precise placement (delineation) of physical features
(graphical)
Descriptive
Mapping
Analysis involves investigation of spatial relationships
(numerical)
Prescriptive
Modeling
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

3. Workshop on GIS Modeling (Part 1)
Historical Setting and GIS Evolution
Manual Mapping for 8,000 years
GIS = Geographic Information Systems
…a more recent expression of mapping (40 years)
Computer Mapping automates the cartographic process (70s)
(digital slide show WorldZoom)
Spatial Database Management links computer mapping techniques with traditional database capabilities (80s)
(digital slide show RealEstate)
Map Analysis representation of relationships within and among mapped data (90s)
…the focus of today’s workshop
Multimedia Mapping full integration of GIS, Internet and visualization technologies (00s)
…but that’s another story
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

4. Desktop Mapping Framework (Vector, Discrete)
Workshop on GIS Modeling (Part 1)
Desktop Mapping Framework (Vector, Discrete)
Click on…
Select Theme
Zoom Pan
Info
Tool
Theme
Table
Distance :
Object ID
X,Y
Feature Species etc.
: :
Object ID Aw
Discrete, irregular map features (objects)
Spatial
Table
Attribute
Geo-Query…
Query
Builder
…identify tall
aspen stands
Big …over 400,000m2 (40ha)?
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

5. Manual GIS (Geo-query circa 1950)
1) Index Card with series of numbered holes around the edge and written description/data in the center
Hole
Index card (tray) 1 2 3 4 5 6 7 8 9 10
Timber Stand Map (wall)
Spatial Table
(spatial objects)
Where
2) Special Punch was used to notch-out the hole assigned to a particular characteristic (attribute), such as #11 notch = Douglas fir timber type
Notch
#11 12 13 14 15
3) Pass a long Needle through the stack of cards and lift…
Cards pulled up…
Hole
… DO NOT have characteristic
Query Tray holds all of the index cards for a project area
5) Card ID# identifies the timber stand polygons from the search and the appropriate locations are shaded—
…a “Database-entry Geo-query”
#57
#57
Cards falling down…
… HAVE characteristic
Notch
Data Table
(attribute records)
What
4) Repeat using the search
results sub-set for more characteristics
(Berry)

6. Workshop on GIS Modeling (Part 1)
MAP Analysis Framework (Raster, Continuous)
(Short Exercise #1)
Click on…
Zoom Pan Rotate
Display
Shading
Manager
Map
Analysis
…calculate a slope map and drape on the elevation surface
Grid Analytics…
Continuous, regular grid cells (objects)
Points, Lines, Polygons and Surfaces :
--, --, --, --,
--, 2438, --,
Grid
Table
2D contour map of elevation default display (Tutor25 dB)– polygons of 200-foot interval range
Click Layer Mesh button– analysis grid superimposed; note elevation values interpolated “on-the-fly” as more than one elevation value in a grid cell
Click Use Cells button– switches to grid display type; each cell shows the elevation value stored at that location; note single value per cell
Click 3D Toggle button– switches to 3D Grid display
Press Zoom In button– drag a rectangular portion of the top of the mountain to enlarge; move cursor to display values
Press Zoom Out button– click and drag (down) to resize to a smaller plot
Press Reset View button– resets to the default plot
Double-click on the map– pops up Data drill down window; move cursor around and note the “stack” of map values for different locations
Press Use Cells button– switches to 3D wireframe plot
Click Map Analysis button– select Neighbors class and Slope function; enter “SLOPE Elevation Fitted FOR Slopemap”; move cursor around to inspect slope values… red (gentle) to green (steep)
From the Main menu, Windows  Elevation– to restore the 3D Elevation display
From the Main menu, Map  Overlay  Slopemap– to graphically overlay the Slopemap on the Elevation surface; note that the gentle areas (red) and the steep areas (green) align with the correct terrain features depicted on the surface
…minimize MapCalc and proceed to the next slide
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

7. Calculating Slope and Flow (Map Analysis)
Workshop on GIS Modeling (Part 1)
Calculating Slope and Flow (Map Analysis)
Elevation Surface
(Berry)
Inclination of a fitted plane to a location and its eight surrounding elevation values
Slope (47,64) = 33.23%
Slope map draped
on Elevation
Slope map %
Total number of the steepest downhill paths flowing into each location
Flow (28,46) = 451 Paths
Flow map draped
on Elevation
Flow map
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

8. Workshop on GIS Modeling (Part 1)
Deriving Erosion Potential & Buffers
Workshop on GIS Modeling (Part 1)
Erosion Potential
Flowmap
Slopemap
Slope_classes
Flow_classes
Flow/Slope
Erosion_potential
Reclassify
Overlay
Erosion_potential
But all buffer-feet are not the same…
(slope/flow Erosion_potential)
…reach farther in areas of high erosion potential
Protective Buffers
Simple Buffer
Streams
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

9. Workshop on GIS Modeling (Part 1)
Calculating Effective Distance (variable-width buffers)
Erosion_potential
Streams
Erosion Buffers
Distance
Distance away from the streams is a function of the erosion potential (Flow/Slope Class) with intervening heavy flow and steep slopes computed as effectively closer than simple distance— “as the crow walks”
Effective Buffers
(digital slide show VBuff2)
Effective Erosion Distance
Close
Far
Heavy/Steep
(far from stream)
Light/Gentle
(close)
Simple Buffer
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

10. Erosion Potential Buffer Model (MapCalc script)
Simple erosion potential model– based on terrain slope and flow
(Short Exercise #2)
See Default.htm
Workshop CD
Bighorn_erosion.scr Script
…extended to derive a Variable-width Buffer
(Full Exercise #2)
(Berry)

11. Workshop on GIS Modeling (Part 1)
Basic Grid Structure
…a Grid Map consists of a matrix of numbers with a value indicating the characteristic or condition at each grid cell location—geo-registered set of Grid Layers
Lines
Fill
Layer Mesh
Grid Map
…the Analysis Frame
provides consistent “parceling” needed
for map analysis and extends Points, Lines and Areas to Surfaces
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

12. Recognizing Data & Display Types
Workshop on GIS Modeling (Part 1)
Recognizing Data & Display Types
Data Types
Numerical Distribution —
Nominal, Ordinal (Qualitative)
Interval, Ratio (Quantitative)
Binary (Boolean)
Geographical Distribution —
Choropleth (Discrete)
Isopleth (Continuous)
Display Types
Display Form — 2D or 3D
Display Structure — Grid or Lattice
Display Data Type — Discrete or Continuous
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.

13. R to V– connecting grid centroids, sides and edges (line smoothing)
Vector to/from Raster
V to R– burning the points, lines and areas into the grid (fat, thin and split)
Points—
Containing
Cell
Lines Polygons
R to V– connecting grid centroids, sides and edges (line smoothing)
Points—
Cell
Centroid
Old saying—“…raster is faster, but vector is corrector”
Vector— “precise” placement of spatial objects
Grid— “accurate” characterization of spatial relationships
(Berry)

14. Accuracy versus Precision
The Wikipedia defines Accuracy as “the degree of veracity” (exactness) while Precision as “the degree of reproducibility” (repeatable)
High Accuracy
but Low Precision
High Precision
but Low Accuracy
Accuracy describes the closeness of arrows to the bull’s-eye at the target center (actual/correct)
Precision relates to the size of the cluster of arrows— grouped tightly together is considered precise
Handheld GPS unit
Precision GPS unit
Accuracy vs. Precision
…the “target analogy” compares measurements to the pattern of arrows shot at a target
(Berry)

15. Superimposed interpretation boundaries
Classification versus Delineation (spatial perspective)
Superimposed interpretation boundaries
Precision = delineation (Where)
Interpreter A
Interpreter B
Interpreter C
Vegetation Parcel
Mapping
Photo Interpreter A
Cottonwood
Photo Interpreter C
Photo Interpreter B
Ponderosa Pine
Accuracy = classification (What)
Classification Accuracy (What)  Delineation Precision (Where)
(Berry)

16. Average of the three cost surfaces
Model Accuracy/Precision (spatial modeling perspective)
Housing Density
Road Proximity
Sensitive Areas
Visual Exposure
Most
Preferred
Least
Routing Criteria
Calibrate
Expert
Opinion
Homeowners
Environmentalists
Engineers
HD & VE times 10
RP & SA times 10
HD & RP times 10
…cognitive
mapping has
no definitive
right/wrong
solution—
Most
Preferred
Weight
Stakeholder
Values
Combined
Solution
Start
End
Average of the three cost surfaces
Optimal Path
Optimal
Corridor
Start
End
Engineers
Environmentalists
Homeowners
Individual
Solutions
(Berry)

17. Workshop on GIS Modeling (Part 1)
…but before we leave Introduction & Data Considerations to tackle Spatial Analysis (operations for reclassify, overlay, distance and neighbors), any…
Questions?
Questions?
(Berry)
Joseph K. Berry, BA_SIS, Inc. All Rights Reserved.