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Lab 3: Spatial Analysis for Public Health

The goal of this exercise is to learn about some of the spatial analysis capabilities in ArcGIS.  Do either Part 1 or Part 2 and also Parts 3, 4, and 5.  If you do both Parts 1 and 2 you will receive extra credit.   

Part 1: West Nile Virus

On the course Sakai Site go to the Exercises Folder under Resources.  There is a folder called West Nile Virus which has two files, a word document which is the exercise and a zipped data file. Download both and do the exercise. Answer all of the questions in the exercise and type them out. Also, submit at least 3 maps you produce in the exercise.

Part 2: Environmental Equity and Air Toxics

On the course Sakai Site go to the Exercises Folder under Resources.  There is a folder called Environmental Equity and Air Toxics which has two files, a word document which is the exercise and a zipped data file. Download both and do the exercise. Answer all of the questions in the exercise and type them out.  Also, submit at least 3 of the 5 items listed in the section entitled “Submit your work.”

Part 3: Descriptive Spatial Statistics in ArcGIS

Go through the free ESRI Virtual Campus Training Seminar called "Introduction to Spatial Pattern Analysis."  You won't need a code for this training seminar.  After completing this seminar you should understand the following concepts and methods: Average Nearest Neighbor, Getis-Ord G, Ripley's K, Moran's I, Anselin's Local Moran's I, among others. Then, go through the course called "Exploring Spatial Patterns in Your Data Using ArcGIS 10."  You will need a code for this course. After completing this exercises you should understand the following concepts and methods: mean center, median center, directional distribution tools (distributional ellipse), histograms, normal QQ plot, Voronoi map, semivariogram, spatial autocorrelation, interpolation.  

Download the following dataset to practice with these tools- http://www.unc.edu/~emch/gisph/CAdata.zip.

Section 1: Measuring Geographic Distributions

In ArcGIS under the "Measuring Geographic Distributions" tools of the "Spatial Statistics" toolbox run the following programs using the towns point layer: 1. Central feature, 2. Mean Center (without weighting), 3. Mean Center (weighted by the population field), 4. Directional Distribution (Standard Deviational Ellipse) using 1 SD, 5. Standard Distance using 1 SD.  Make a map or maps that labels all of the features that you created.  Then describe what each one means.

Section 2: Analyzing Spatial Patterns

In ArcGIS under the "Analyzing Spatial Patterns" tools of the "Spatial Statistics" toolbox run the global Moran's I program using the NastyWater variable and print the result.  Is NastyWater spatially autocorrelated in California?  If so, how much and what does that mean?  Calculate the average nearest neighbor distance on towns.  Are the towns clustered or dispersed?  What is the average nearest neighborhood value and Z-score? Calculate the Getis-Ord General G Index on NastyWater.  What is the value and Z-score? Is there high or low clustering?.

Section 3: Mapping Clusters

In ArcGIS under the "Mapping Clusters" tools of the "Spatial Statistics" toolbox run the program called "Hot Spot Analysis: Getis-Ord Gi*" for the NastyWater variable  Use a distance band of 10,000.  The result is a table that has a new field in it called Gi10000.  Map that out with the small numbers (cool spots) in blue points and the large numbers (hot spots) in red.  Does there seem to be spatial clustering of those hot spots? Then calculate the Anselin's Local Moran's I values for the NastyWater variable using the Town layer.  Map the local Moran's I value using red and blue?  Where is there high local spatial autocorrelation of NastyWater and what does that mean?

Part 4: Inferential Statistics in ArcGIS

First go through the free ESRI Virtual Campus Training Seminar called “Beyond Where: Using Regression Analysis to Explore Why.” Then do the ESRI Virtual Campus web course called "Regression Analysis Using ArcGIS." You should know the difference between OLS and GWR regression when you've completed this seminar. 

Part 5: Network Analysis in ArcGIS

Go through the free ESRI Virtual Campus Training Seminar called "Introduction to ArcGIS Network Analyst in ArcGIS Desktop 10."  You should know what network distance is after you've completed this exercise.  You should also be able to calculate service areas and closest facilities.  Once you are done, write a paragraph describing a hypothetical public health network analysis application.  If you plan to use Network Analyst tools for your class project or research then you should also do the Web Course called “Network Analysis Using ArcGIS 10” for which you’ll need a code.

Lab Deliverable Summary: Print out all of the outputs, put your name on them, and give them to the instructor. They include: Part 1: answers to questions OR Part 2: answers to questions and 3 items under Submit Your work section. Part 3: map or maps showing the 3 geographic distribution summary statistics and a description of what each means, Moran's I result printout and description of what the result means, average nearest neighbor calculation result and description of what it means, Getis-Ord General G Index result and description of what it means. In Part 3, also organize the deliverables by the three sections that are listed. In Part 4, write a paragraph describing a hypothetical GWR application and what you will get out of using GWR versus OLS regression.  In Part 5, print the paragraph describing a hypothetical public health network analysis application.