Geostatistical Analyst - An Introduction
2013 Esri International User Conference July 8–12, 2013 | San Diego, California Technical Workshop
Geostatistical Analyst An Introduction Steve Lynch and Eric Krause Redlands, CA
Esri UC2013 . Technical Workshop .
Presentations of interest… •
EBK – Robust kriging as a GP tool -
•
Surface Interpolation in ArcGIS -
•
Wednesday 5:30pm – 6:00pm Demo theater
Geostatistical Simulations - Applications in Worst Case Scenarios -
•
Wednesday 4:30pm – 5:30pm Demo theater
Areal Interpolation – Performing polygon-to-polygon predictions -
•
Wednesday 10:00am – 10:30am Demo theater
Thursday 11:00am – 11:30am Demo theater
Designing and Updating a Monitoring Network -
Thursday 11:30am – 12:00pm Demo theater
•
•
Concepts and Applications of Kriging -
Tuesday 10:15am – 11:30am (room 04)
-
Wednesday 3:15pm – 4:30pm (room 04)
Creating Surfaces -
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Wednesday 8:30am – 9:45am (Room 03)
•
Geostatistical Analyst - An Introduction
•
Tuesday 8:30am – 9:45am (room 05 A)
•
Wednesday 1:30pm – 2:45pm (room 05 A)
Outline
• What is • geostatistics? • Geostatistical Analyst? • New in 10+ • Interpolation workflow • Demonstrations • Supplementary information • Questions / Answers
Esri UC2013 . Technical Workshop .
What is geostatistics ?
The statistics of spatially correlated data
Semivariogram Sill
Nugget Range
Esri UC2013 . Technical Workshop .
Semivariogram Semivariogram(distance h) = 0.5 * average [ (valuei– valuej)2]
Esri UC2013 . Technical Workshop .
What is geostatistics ?
The statistics of spatially correlated data
Esri UC2013 . Technical Workshop .
Geostatistical Analyst - Overview •
Interactive -
•
Exploratory Spatial Data Analysis tools Variography Kriging Other interpolation methods Cross validation
Geoprocessing toolbox -
Esri UC2013 . Technical Workshop .
Interpolation Sampling Network Design Simulation Utilities Conversion
Where is Geostatistical Analyst used?
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Where is Geostatistical Analyst used?
Esri UC2013 . Technical Workshop .
Experiment conducted by the US EPA 20 years ago Isaaks & Srivastava, 1989. An Introduction to Applied Geostatistics.
•
12 independent reputable geostatisticians
•
Given the same data
•
Asked to perform the same straightforward estimation
•
Results were widely different
•
Different -
data analysis conclusions variogram models and choice of kriging type searching neighborhoods.
Esri UC2013 . Technical Workshop .
Geostatistical Analyst – Toolbar and Toolbox
Esri UC2013 . Technical Workshop .
Geostatistical Wizard Demonstration
Esri UC2013 . Technical Workshop .
What’s new in 10 – Optimize buttons Local Polynomial Interpolation • Kriging •
-
Esri UC2013 . Technical Workshop .
Nugget, partial sill and other(s), are optimized using cross validation with focus on the estimation of the range parameter.
What’s new in 10.0+ •
Areal Interpolation -
•
Empirical Bayesian Kriging (EBK) -
•
predictions can be made from one set of polygons to another set of polygons builds local models on subsets of the data, which are then combined together to create the final surface.
Normal Score Transformation -
Multiplicative Skewing approximation method
Esri UC2013 . Technical Workshop .
Interpolation workflow •
Exploratory Spatial Data Analysis (ESDA)
•
Interpolate -
•
estimation of values at unsampled locations based on known values
Goodness of fit
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Exploratory Spatial Data Analysis Where is the data located? • What are the values at the data points? • How does the location of a point relate to its value? •
Esri UC2013 . Technical Workshop .
Exploratory Spatial Data Analysis (ESDA)
Esri UC2013 . Technical Workshop .
Exploratory Spatial Data Analysis (ESDA)
Esri UC2013 . Technical Workshop .
Kriging •
Concepts and Applications of Kriging -
Tuesday 10:15am – 11:30am (room 04)
-
Wednesday 3:15pm – 4:30pm (room 04)
Outline • Introduction to kriging • Best practices • Fitting a proper model • Variography, transformations, isotropy, stationarity • Comparing models using cross validation • Interpreting results
•
Empirical Bayesian Kriging – Robust kriging as a GP tool -
Wednesday 10:00am – 10:30am Demo theater
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
What is kriging? It is a geostatistical interpolation technique
•
that models the spatial correlation of point measurements
•
to estimate values at unmeasured locations.
•
Associates uncertainty with the predictions Correlation
•
Distance Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Kriging Demonstration
Esri UC2013 . Technical Workshop .
Empirical Bayesian Kriging (EBK) •
automates the most difficult aspects of building a valid kriging model
•
estimates the semivariogram through repeated simulations
•
can handle non-stationary input data. Unlike other kriging methods (use weighted least squares), the semivariogram parameters in EBK are estimated using restricted maximum likelihood (REML). New in ArcGIS 10.1
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
For a given distance h, the semivariogram model: γ(h)= Nugget + b|h|α
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Empirical Bayesian Kriging (cont) •
Advantages -
•
Requires minimal interactive modeling Allows accurate predictions of non-stationary data More accurate than other kriging methods for small datasets Geoprocessing tool
Disadvantages -
Processing is slower than other kriging methods. Cokriging and anisotropy are unavailable.
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Empirical Bayesian Kriging Demonstration
Esri UC2013 . Technical Workshop .
Goodness of fit / Model acceptance
•
Subset Features
•
Cross Validation
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Cressie, 1990 •
Cross validation does not prove that the model is correct,
•
merely that it is not grossly incorrect.
Esri UC2013 . Technical Workshop .
Cross validation Demonstration
Esri UC2013 . Technical Workshop .
Geostatistical layer Method and parameters • Pointer to the data • Dynamic •
Esri UC2013 . Technical Workshop .
Output = Prediction, Prediction SE, Probability, Quantile, Condition number
Esri UC2013 . Technical Workshop .
Geostatistical layer Demonstration
Esri UC2013 . Technical Workshop .
Areal Interpolation •
reaggregation of data from one set of polygons to another set of polygons
New in ArcGIS 10.1
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Areal Interpolation Demonstration
Esri UC2013 . Technical Workshop .
Demo theater Areal Interpolation Wednesday 5:30pm – 6:00pm
Esri UC2013 . Technical Workshop .
Simple kriging
N = 500 100 8
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Demo theater Geostatistical Simulations Thursday 11:00am – 11:30am
Esri UC2013 . Technical Workshop .
Interpolation with Barriers •
Kernel interpolation
•
Diffusion interpolation
? Cost Raster Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Create Spatially Balanced Points •
Monitor road pollution
•
Convert roads to raster
•
High value = busy road
•
Low value = quite road
Sampling Network Design Esri UC2013 . Technical Workshop .
Create Spatially Balanced Points (cont.)
Sampling Network Design Esri UC2013 . Technical Workshop .
Densify Sampling Network •
Used kriging to create: -
•
Prediction surface Standard error of prediction
Want to add 2 new sites
Sampling Network Design Esri UC2013 . Technical Workshop .
Densify Sampling Network (Cont.)
Sampling Network Design Esri UC2013 . Technical Workshop .
Demo theater Designing and Updating a Monitoring Network Thursday 11:30am – 12:00pm
Esri UC2013 . Technical Workshop .
resources.arcgis.com
Esri UC2013 . Technical Workshop .
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
http://esripress.esri.com
Esri UC2013 . Technical Workshop .
Thank you… Please fill out the session evaluation
First Offering ID: 1174 Second Offering ID: 1294
Online – www.esri.com/ucsessionsurveys Paper – pick up and put in drop box Esri UC2013 . Technical Workshop .
Geostatistical Analyst An Introduction Steve Lynch and Eric Krause Redlands, CA
Esri UC2013 . Technical Workshop .
Presentations of interest… •
EBK – Robust kriging as a GP tool -
•
Surface Interpolation in ArcGIS -
•
Wednesday 5:30pm – 6:00pm Demo theater
Geostatistical Simulations - Applications in Worst Case Scenarios -
•
Wednesday 4:30pm – 5:30pm Demo theater
Areal Interpolation – Performing polygon-to-polygon predictions -
•
Wednesday 10:00am – 10:30am Demo theater
Thursday 11:00am – 11:30am Demo theater
Designing and Updating a Monitoring Network -
Thursday 11:30am – 12:00pm Demo theater
•
•
Concepts and Applications of Kriging -
Tuesday 10:15am – 11:30am (room 04)
-
Wednesday 3:15pm – 4:30pm (room 04)
Creating Surfaces -
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Wednesday 8:30am – 9:45am (Room 03)
•
Geostatistical Analyst - An Introduction
•
Tuesday 8:30am – 9:45am (room 05 A)
•
Wednesday 1:30pm – 2:45pm (room 05 A)
Outline
• What is • geostatistics? • Geostatistical Analyst? • New in 10+ • Interpolation workflow • Demonstrations • Supplementary information • Questions / Answers
Esri UC2013 . Technical Workshop .
What is geostatistics ?
The statistics of spatially correlated data
Semivariogram Sill
Nugget Range
Esri UC2013 . Technical Workshop .
Semivariogram Semivariogram(distance h) = 0.5 * average [ (valuei– valuej)2]
Esri UC2013 . Technical Workshop .
What is geostatistics ?
The statistics of spatially correlated data
Esri UC2013 . Technical Workshop .
Geostatistical Analyst - Overview •
Interactive -
•
Exploratory Spatial Data Analysis tools Variography Kriging Other interpolation methods Cross validation
Geoprocessing toolbox -
Esri UC2013 . Technical Workshop .
Interpolation Sampling Network Design Simulation Utilities Conversion
Where is Geostatistical Analyst used?
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Where is Geostatistical Analyst used?
Esri UC2013 . Technical Workshop .
Experiment conducted by the US EPA 20 years ago Isaaks & Srivastava, 1989. An Introduction to Applied Geostatistics.
•
12 independent reputable geostatisticians
•
Given the same data
•
Asked to perform the same straightforward estimation
•
Results were widely different
•
Different -
data analysis conclusions variogram models and choice of kriging type searching neighborhoods.
Esri UC2013 . Technical Workshop .
Geostatistical Analyst – Toolbar and Toolbox
Esri UC2013 . Technical Workshop .
Geostatistical Wizard Demonstration
Esri UC2013 . Technical Workshop .
What’s new in 10 – Optimize buttons Local Polynomial Interpolation • Kriging •
-
Esri UC2013 . Technical Workshop .
Nugget, partial sill and other(s), are optimized using cross validation with focus on the estimation of the range parameter.
What’s new in 10.0+ •
Areal Interpolation -
•
Empirical Bayesian Kriging (EBK) -
•
predictions can be made from one set of polygons to another set of polygons builds local models on subsets of the data, which are then combined together to create the final surface.
Normal Score Transformation -
Multiplicative Skewing approximation method
Esri UC2013 . Technical Workshop .
Interpolation workflow •
Exploratory Spatial Data Analysis (ESDA)
•
Interpolate -
•
estimation of values at unsampled locations based on known values
Goodness of fit
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Exploratory Spatial Data Analysis Where is the data located? • What are the values at the data points? • How does the location of a point relate to its value? •
Esri UC2013 . Technical Workshop .
Exploratory Spatial Data Analysis (ESDA)
Esri UC2013 . Technical Workshop .
Exploratory Spatial Data Analysis (ESDA)
Esri UC2013 . Technical Workshop .
Kriging •
Concepts and Applications of Kriging -
Tuesday 10:15am – 11:30am (room 04)
-
Wednesday 3:15pm – 4:30pm (room 04)
Outline • Introduction to kriging • Best practices • Fitting a proper model • Variography, transformations, isotropy, stationarity • Comparing models using cross validation • Interpreting results
•
Empirical Bayesian Kriging – Robust kriging as a GP tool -
Wednesday 10:00am – 10:30am Demo theater
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
What is kriging? It is a geostatistical interpolation technique
•
that models the spatial correlation of point measurements
•
to estimate values at unmeasured locations.
•
Associates uncertainty with the predictions Correlation
•
Distance Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Kriging Demonstration
Esri UC2013 . Technical Workshop .
Empirical Bayesian Kriging (EBK) •
automates the most difficult aspects of building a valid kriging model
•
estimates the semivariogram through repeated simulations
•
can handle non-stationary input data. Unlike other kriging methods (use weighted least squares), the semivariogram parameters in EBK are estimated using restricted maximum likelihood (REML). New in ArcGIS 10.1
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
For a given distance h, the semivariogram model: γ(h)= Nugget + b|h|α
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Empirical Bayesian Kriging (cont) •
Advantages -
•
Requires minimal interactive modeling Allows accurate predictions of non-stationary data More accurate than other kriging methods for small datasets Geoprocessing tool
Disadvantages -
Processing is slower than other kriging methods. Cokriging and anisotropy are unavailable.
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Empirical Bayesian Kriging Demonstration
Esri UC2013 . Technical Workshop .
Goodness of fit / Model acceptance
•
Subset Features
•
Cross Validation
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Cressie, 1990 •
Cross validation does not prove that the model is correct,
•
merely that it is not grossly incorrect.
Esri UC2013 . Technical Workshop .
Cross validation Demonstration
Esri UC2013 . Technical Workshop .
Geostatistical layer Method and parameters • Pointer to the data • Dynamic •
Esri UC2013 . Technical Workshop .
Output = Prediction, Prediction SE, Probability, Quantile, Condition number
Esri UC2013 . Technical Workshop .
Geostatistical layer Demonstration
Esri UC2013 . Technical Workshop .
Areal Interpolation •
reaggregation of data from one set of polygons to another set of polygons
New in ArcGIS 10.1
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Areal Interpolation Demonstration
Esri UC2013 . Technical Workshop .
Demo theater Areal Interpolation Wednesday 5:30pm – 6:00pm
Esri UC2013 . Technical Workshop .
Simple kriging
N = 500 100 8
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Demo theater Geostatistical Simulations Thursday 11:00am – 11:30am
Esri UC2013 . Technical Workshop .
Interpolation with Barriers •
Kernel interpolation
•
Diffusion interpolation
? Cost Raster Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Create Spatially Balanced Points •
Monitor road pollution
•
Convert roads to raster
•
High value = busy road
•
Low value = quite road
Sampling Network Design Esri UC2013 . Technical Workshop .
Create Spatially Balanced Points (cont.)
Sampling Network Design Esri UC2013 . Technical Workshop .
Densify Sampling Network •
Used kriging to create: -
•
Prediction surface Standard error of prediction
Want to add 2 new sites
Sampling Network Design Esri UC2013 . Technical Workshop .
Densify Sampling Network (Cont.)
Sampling Network Design Esri UC2013 . Technical Workshop .
Demo theater Designing and Updating a Monitoring Network Thursday 11:30am – 12:00pm
Esri UC2013 . Technical Workshop .
resources.arcgis.com
Esri UC2013 . Technical Workshop .
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
Esri UC2013 . Technical Workshop . Geostatistical Analyst - An Introduction
http://esripress.esri.com
Esri UC2013 . Technical Workshop .
Thank you… Please fill out the session evaluation
First Offering ID: 1174 Second Offering ID: 1294
Online – www.esri.com/ucsessionsurveys Paper – pick up and put in drop box Esri UC2013 . Technical Workshop .
