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A Map-ematical Framework for Quantitative Analysis of Mapped Data…Map Analysis and GIS Modeling for Understanding and Communicating
Spatial Patterns and Relationships within STEM Discipline Contexts
Presentation by
Joseph K. Berry
Adjunct Faculty in Natural Resources, Warner College of Natural Resources, Colorado State UniversityAdjunct Faculty in Geosciences, Department of Geography, University of Denver
Principal, Berry & Associates // Spatial Information Systems
Email: [email protected] — Website: www.innovativegis.com/basis
This PowerPoint with notes and online links to further reading is posted at
www.innovativegis.com/basis/Present/Mapematics_2015/
“They who don’t know, don’t know they don’t know”
A Brown Bag Lunch event hosted by the University of DenverCenter for Statistics and Visualization and Department of Geography & the Environment — September 19, 2014
This presentation describes a comprehensive framework for map analysis and modeling concepts and procedures as direct spatial extensions of traditional mathematics and statistics enabling individuals with
minimal or no GIS background to develop spatial reasoning an problem solving skills—”thinking with maps.”
…three major considerations will influence map analysis/modeling future development— Mathematical Framework, Data Structure and Educational Approach
This presentation describes a comprehensive framework for map analysis and modeling concepts and procedures as direct spatial extensions of traditional mathematics and statistics enabling individuals with
minimal or no GIS background to develop spatial reasoning an problem solving skills—”thinking with maps.”
…three major considerations will influence map analysis/modeling future development— Mathematical Framework, Data Structure and Educational Approach
Mapping vs. Analyzing (Processing Mapped Data)
Global Positioning System
(locate and navigate)
Geographic Information Systems
(map and analyze)
GPS/GIS/RS
(Berry)
…GIS is a Technological Tool involving —
−Mapping that creates a spatial representation of an area
−Display that generates visual renderings of a mapped area
−Geo-query that searches for map locations having a specified classification, condition or characteristic
“Map”
(Descriptive Mapping)
“Analyze”
… and an Analytical Tool involving —
−Spatial Mathematics that applies scalar mathematical formulae to account for geometric positioning, scaling, measurement and transformations of mapped data
−Spatial Analysis that investigates the contextual relationships within and among mapped data layers
−Spatial Statistics that investigates the numerical relationships within and among mapped data layers
(Prescriptive Modeling)
Mega-Technologies… …for the 21st Century
(Biotechnology) (Nanotechnology)
Remote Sensing
(measure and classify)
Descriptive Mapping(Cartographic)
Prescriptive Modeling(Analytic)
Spatial Statistics Operations Spatial Analysis Operations
A Mathematical Structure for Map Analysis/Modeling
Geotechnology RS – GIS – GPS
Grid-basedMap Analysis
Toolbox
(Berry)
Esri Spatial Analyst operations…over 170 individual “tools”
Matrix of Numbers
www.innovativegis.com/basis/BeyondMappingSeries/, Book IV, Topic 9 for more discussion
A Map-ematical Framework
Traditional math/stat procedures can be extended into
geographic space to support
Quantitative Analysis of Mapped Data
“…thinking analytically with maps”
“Map-ematics”Map Stack
Maps as Data, not Pictures
Vector & Raster — Aggregated & Disaggregated
Qualitative & Quantitative
“Map Variables”
(Continuous, Map Surfaces) Map Analysis/Modeling
Analytical ToolTechnological Tool
Mapping/Geo-Query (Discrete, Spatial Objects)
Geo-registered
Analysis Frame
…organized set of numbers
Spatial Analysis Operations (Geographic Context)
Spatial Analysis extends the basic set of discrete map features (points, lines and polygons) to
map surfaces that represent continuous geographic space as a set of contiguous grid cells (matrix),thereby providing a Mathematical Framework for map analysis and modeling of the
Contextual Spatial Relationships within and among grid map layers
(Berry)
GIS as “Technical Tool” (Where is What) vs. “Analytical Tool” (Why, So What and What if)
Map StackGrid Layer
Map Analysis Toolbox
Basic GridMath & Map Algebra ( + - * / )
Advanced GridMath (Math, Trig, Logical Functions)
Map Calculus (Spatial Derivative, Spatial Integral)
Map Geometry (Euclidian Proximity, Effective Proximity, Narrowness)
Plane Geometry Connectivity (Optimal Path, Optimal Path Density)
Solid Geometry Connectivity (Viewshed, Visual Exposure)
Unique Map Analytics (Contiguity, Size/Shape/Integrity, Masking, Profile)
Mathematical Perspective:
Unique spatial operations
www.innovativegis.com/basis/BeyondMappingSeries/, Book IV, Topic 9 for more discussion
The integral calculates the
area under the curve for any section of a function. Curve
Map Calculus — Spatial Derivative, Spatial IntegralAdvanced Grid Math — Math, Trig, Logical Functions
Spatial Integral
Surface
COMPOSITE Districts WITH MapSurface Average FOR MapSurface_Davg
MapSurface_Davg
…summarizes the values on a surface for specified map areas
(Total= volume under the surface)
Slope draped overMapSurface
0%
65%
Spatial Derivative
…is equivalent to the slope of the tangent plane at a location
SLOPE MapSurface Fitted FOR MapSurface_slope
Fitted PlaneSurface
500’
2500’
MapSurface
Advanced Grid Math
Surface Area
…increases with increasing inclination as a Trig function of the cosine of the slopeangle
S_Area= Fn(Slope)
Spatial Analysis Operations (Math Examples)
Dzxy Elevation
S_area= cellsize / cos(Dzxy Elevation)
ʃ Districts_Average Elevation
Curve
The derivative is the instantaneous “rate of change” of a function and is equivalent to the slope of the tangent line at a point
(Berry)
Seen if new tangent exceeds all previous tangents along the line of sight
Tan = Rise/Run
Rise
Run
Viewshed
Splash
Solid Geometry Connectivity
Spatial Analysis Operations (Distance Examples)
(Berry)
Map Geometry — (Distance, Proximity, Effective Movement, Narrowness)
Plane Geometry Connectivity — (Optimal Path, Optimal Path Density)
Solid Geometry Connectivity — (Viewshed, Visual Exposure)
Proximity
…from a point to everywhere…
HighestWeightedExposure
SumsViewerWeights
Counts # Viewers
270/621= 43% of the entire road network is connected
Visual Exposure
Distance
Shortest straight line between two points…
Travel-TimeSurface
Movement (absolute/relative barriers)
…not necessarily straight lines (movement)
HQ (start)On Road
26.5 minutes
…farthest away by truck
Off RoadAbsolute Barrier
On + Off Road
96.0 minutes
…farthest away by truck, ATV and hiking
Off RoadRelative Barriers
Plane Geometry
Connectivity
…like a raindrop, the “steepest downhillpath” identifies the optimal route(Quickest Path)
Farthest(end)
HQ (start) Truck = 18.8 min
ATV = 14.8 min Hiking = 62.4 min
Spatial Statistics Operations (Numeric Context)
(Berry)
Spatial Statistics seeks to map the variation in a data set instead of focusing on a single typical response (central tendency),
thereby providing a Statistical Framework for map analysis and modeling of the
Numerical Spatial Relationships within and among grid map layers
GIS as “Technical Tool” (Where is What) vs. “Analytical Tool” (Why, So What and What if)
Map StackGrid Layer
Map Analysis Toolbox
Basic Descriptive Statistics (Min, Max, Median, Mean, StDev, etc.)
Basic Classification (Reclassify, Contouring, Normalization)
Map Comparison (Joint Coincidence, Statistical Tests)
Unique Map Statistics (Roving Window and Regional Summaries)
Surface Modeling (Density Analysis, Spatial Interpolation)
Advanced Classification (Map Similarity, Maximum Likelihood, Clustering)
Predictive Statistics (Map Correlation/Regression, Data Mining Engines)
Statistical Perspective:
Unique spatial operations
www.innovativegis.com/basis/BeyondMappingSeries/, Book IV, Topic 9 for more discussion
Histogram
706050403020100 80
In Geographic Space, the typical value forms a horizontal plane implying
the average is everywhere
X= 22.6
Avg=22.6
Spatial Statistics (Linking Data Space with Geographic Space)
Continuous Map Surface
Spatial Distribution
Surface Modeling techniques are used to derive a continuous map surface from discrete point data– fits a Surface to the data (maps the variation).
Geo-registered Sample Data
Discrete Sample Map
SpatialStatistics
(Berry)
…lots of NE locations exceed Mean + 1Stdev
X + 1StDev= 22.6 + 26.2
= 48.8
Unusually high
values+StDev
Average
Standard Normal Curve
Average = 22.6
Numeric Distribution
StDev =
26.2(48.8)
Non-Spatial Statistics
In Data Space, a standard normal curve can be fitted to the data to identify the “typical value” (average)
Roving Window (weighted average)
Neighboring Parcel
Slope(Percent)
Map Clustering:
Elevation(Feet)
Advanced Classification (Clustering)
Latitude
Longitude X axis = Elevation (0-100 Normalized)Y axis = Slope (0-100 Normalized)
Elevation vs. Slope Scatterplot
Data Space
Slope draped on Elevation
Slo
pe
Elev
Entire MapExtent
Spatially Aggregated CorrelationScalar Value – one value represents the overall non-spatial relationship between the two map surfaces
…where x = Elevation value and y = Slope valueand n = number of value pairs
r =
…1 large data table with 25rows x 25 columns =
625 map values for map wide summary
Cluster 1
Cluster 2
(Berry)
Spatial Statistics Operations (Data Mining Examples)
“data pair” of map values
(Lon,Lat,Value)
+
“data pair” plots here in…
Data Space
r = .432 Aggregated
Geographic Space
+
Geographic Space
…as similar as can be WITHIN a cluster …and as different as can be BETWEEN clusters
Map of the Correlation
Predictive Statistics (Correlation)
Map Correlation:
Slope(Percent)
Elevation(Feet)
Latitude
Longitude
Roving Window
Localized CorrelationMap Variable – continuous quantitative surface represents the localized spatial relationship between the two map surfaces
…625 small data tables within 5 cell reach =
81map values for localized summary
GIS Evolution
The Early Years
Revisit Analytics(2020s)
GIS Development Cycle (…where we’re heading)
Map Analysis (1990s)
Computer Mapping(1970s)
Spatial dB Mgt (1980s)
The Early Years
Contemporary GIS
GeoWeb(2000s)
Revisit Geo-reference (2010s)
Future Directions
Mapping focus
Data/Structure focus
Analysis focus
…about every decade
Cube(6 squares)
3D Solid(X,Y,Z Data)
Future Directions
Square(4 sides)
2D Planar(X,Y Data)
Cartesian Coordinates
(Berry)
Hexagon(6 sides)
Today
Future
PentagonalDodecahedral(12 pentagons)
Today
Future
Grid-based Map Data Structure (geo-registered matrix of map values)
(Berry)
Conceptual Spreadsheet (73 x 144)
#Rows= 73 #Columns= 144 = 10,512 grid cells
…each 2.50 grid cell is about 140mi x 140mi
18,735mi2…from Lat/Lon
“crosshairs to grid cells”
that contain map
values indicating characteristics or conditions at each
grid location
Lat/Lon
The easiest way to conceptualize a grid map is as an Excel spreadsheet with each cell in the table corresponding to a Lat/Lon grid space (location)
and each value in a cell representing the characteristic or condition (information) of a mapped variable occurring at that location.
…maximum Lat/Lon decimal degree resolution is
a four-inch squareanywhere in the world
The Latitude/Longitude grid forms a continuous surface for geographic referencing
where each grid cell represents a given portion of the earth’ surface.
300
Grid Lines
90
2.50 Latitude/Longitude Grid (140mi grid cell size)
Coordinate of first grid cell is 900 N 00 E
AnalysisFrame
(grid “cells”)
“Pours” the values into the Analysis Frame —
Georegistered Map Stack
…the bottom line is that…
All spatial topology is inherent in the grid.
Lat/Lon serves as a Universal dB KeyUniversal dB Key for joining data tables based on location
The lion’s share of the growth has been GIS’s ever expanding capabilities as a “technical tool” for corralling vast amounts of spatial data and providing near instantaneous access to remote sensing images, GPS navigation, interactive maps, asset management records, geo-queries and awesome displays.
However, GIS as an “analytical tool” hasn’t experienced the same meteoric rise— in fact it can be argued that the analytic side of GIS has somewhat stalled… partly because of…
(Berry)
…but modern digital“maps are numbers first,
pictures later” and we do mathematical and
statistical things to map variables that moves GIS from—
“Where is What” graphical inventories, to a
“Why, So What and What If” problem solving environment—
“thinking analyticallywith maps”
GIS Education (shifting the current Technical focus to a Pedagogical focus)
TechnologyExperts
“-ists”DomainExperts
“-ologists”
The “-ists” and the “-ologists” Perspectives
(Berry)
SolutionSpace
Together the “-ists” and the “-ologists” frame and develop the Solution for an application.
…understand the “tools” that can be used to display, query and
analyze spatial data
Data and Information focus
…understand the “science” behind spatial relationships that can be
used for decision-making
Knowledge and Wisdom focus
The “-ists” The “-ologists”— and —
GeospatialSpecialists
Why, So What, What If
Spatial Reasoning
Where is What
GIS Expertise
STEMDisciplines
“Public”…under Stakeholder,
Policy & Public auspices
“Policy Makers”
The “-ists” and the “-ologists” Perspectives (toward a much bigger tent)
“Stakeholders”
“Decision Makers”
TechnologyExperts
“-ists”DomainExperts
“-ologists”Solution
Space
Application SpaceGeospatial Technology’s Core
…Decision Makers utilize
the Solution…
(Berry)
Spatial Reasoning
GIS Expertise
We are simultaneously trivializing… …and complicating GIS Technology
…we need to educate people at all levels about the potential,
procedures and pitfalls of quantitative analysis
of mapped data—
SpatialSTEMCurricula
Conclusions/Upshot (from your grandfather's map to mapped data)
(Berry)
– automated the cartographic process where points, lines and areas (spatial objects) defining geographic features on a map are represented as an organized set of X,Y coordinates.
– linked computer mapping capabilities with traditional database management capabilities by assigning an ID# to each spatial object that serves as a common database key between a spatial table (Where) and an attribute table (What).
– developed a comprehensive theory of map analysis where spatial information is represented numerically as continuous spatial distributions (raster), rather than in graphic fashion as discrete spatial objects (vector) identified by inked lines on a map. These digital maps are frequently conceptualized as a set of "floating maps" with a common registration, allowing the computer to "look" down and across the stack of digital maps to
characterize spatial relationships of the mapped data that can be summarized (database queries) or mathematically manipulated (analytic processing).
– the Internet has moved maps and mapping from a “down the hall and to the right” specialist’s domain, to everyone’s desktop, notebook and mobile device. While the bulk of these applications involve navigation, mapping and geo-query (technological), they have fully established the digital map beachhead that sees “maps as data, not just images.”
1) Scientific Use of Spatial Data – SpatialSTEM education will infuse science with “analytical tools” for unlocking radically new understandings of spatial patterns and relationships in their research.
2) Spatial Solutions to Devices – “map-ematical solutions” will be directly tied to automated devices through continued coupling of the Spatial Triad (RS, GIS, GPS) and robotics.
3) Spatial Reasoning and Dialog – GIS models will enable decision-makers to interactively investigate and better communicate “Why, So What and What If” of the probable spatial outcomes/impacts of critical decisions.
See http://www.innovativegis.com/basis/BeyondMappingSeries/BeyondMapping_I/Epilog/BM_I_Epilog.htm for more discussion
Computer Mapping (1970 to 1980)
Spatial Database Management Systems (1980 to 1990)
Map Analysis and GIS Modeling (1990 to 2000)
GeoWeb and Mobile Devices (2000 to 2010)
Tomorrow’s GIS arena will be radically different from the past four decades…
In the future, Geospatial Technology will fully exploit its numerical character by extending…
Driving Forces Moving GIS Beyond Mapping
2) Grid-based map analysis and modeling involving Spatial Analysis and Spatial Statistics are in large part simply spatial extensions of traditional
mathematical and statistical concepts and procedures.
2) Grid-based map analysis and modeling involving Spatial Analysis and Spatial Statistics are in large part simply spatial extensions of traditional
mathematical and statistical concepts and procedures.
1) Solutions to complex spatial problems need to engage “domain expertise” through GIS– outreach to other disciplines to establish spatial reasoning skills
needed for effective solutions that integrate a multitude of disciplinary and general public perspectives..
1) Solutions to complex spatial problems need to engage “domain expertise” through GIS– outreach to other disciplines to establish spatial reasoning skills
needed for effective solutions that integrate a multitude of disciplinary and general public perspectives..
3) The recognition by the STEM community that spatial relationships exist and are quantifiable and the recognition by the GIS community that quantitative
analysis of maps is a reality should be the glue that binds the two perspectives– a common coherent and comprehensive SpatialSTEM approach.
3) The recognition by the STEM community that spatial relationships exist and are quantifiable and the recognition by the GIS community that quantitative
analysis of maps is a reality should be the glue that binds the two perspectives– a common coherent and comprehensive SpatialSTEM approach.
The Bottom Line
“…map analysis quantitative analysis of mapped data”
— not your grandfather’s map
The Bottom Line
“…map analysis quantitative analysis of mapped data”
— not your grandfather’s map
The STEM community will revolutionize how we The STEM community will revolutionize how we conceptualize, utilize and visualizeconceptualize, utilize and visualize spatial relationships… spatial relationships…
… nor his math/stat(Berry)
Online Materials (www.innovativegis.com/Basis/Courses/SpatialSTEM/)
)
This PowerPoint with notes and online links to further reading is posted at
www.innovativegis.com/basis/Present/Mapematics_2015/
Where to Head from Here?
Joseph K. Berry Joseph K. Berry [email protected]@innovativegis.com
eMail Contact
For more papers and presentations on GeotechnologyFor more papers and presentations on Geotechnology
www.innovativegis.comwww.innovativegis.com
For more papers and presentations on GeotechnologyFor more papers and presentations on Geotechnology
www.innovativegis.comwww.innovativegis.com
Website (www.innovativegis.com)
Beyond Mapping Compilation Series (www.innovativegis.com/basis/BeyondMappingSeries/)
…nearly 1000 pages and more than 750 figures in the Series provide a comprehensive and longitudinal perspective of the underlying
concepts, considerations, issues and evolutionary development of modern
geotechnology (RS, GIS, GPS).
THANK YOU for your kind attention– any final thoughts or questions?