Cluster/Outlier Analysis with Rendering (Spatial Statistics) |
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Release 9.2
Last modified January 9, 2009 |
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Given a set of weighted data points, identifies those clusters of points with values similar in magnitude and those clusters of points with very heterogeneous values, then applies a cold-to-hot type of rendering.
Illustration
Usage tips
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The Cluster/Outlier Analysis with Rendering tool combines the Clusters and Outlier Analysis and Z Score Rendering functions.
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Current map layers may be used to define the input feature class. When using layers, only the currently selected features are used in the Local Moran's I operation.
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This tool will only work on the windows operating system. If you are not using windows, please run the Clusters and Outlier Analysis tool by itself.
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The following environment settings affect this tool: Cluster Tolerance, Extent, M Domain, Configuration Keyword, Coordinate System, Output has M Values, Output Spatial Grid, Output has Z Values, Default Z Value, Output XY Domain, and Output Z Domain.
Command line syntax
An overview of the Command Line window
ClustersOutliersRendered_stats <Input_Feature_Class> <Input_Field> <Output_Layer_File> <Output_Feature_Class>
| Parameter | Explanation | Data Type |
| <Input_Feature_Class> |
The feature class for which cluster analysis will be performed. |
Feature Layer |
| <Input_Field> |
The field to be evaluated. |
Field |
| <Output_Layer_File> |
The output layer file to store rendering information. You must include the .lyr extension as part of the file name. |
Layer File |
| <Output_Feature_Class> |
The output feature class to receive the results field and Z score. |
Feature Class |
Command line example
ClustersOutliersRendered VotingDistricts.shp ProIncumbent votediversity.lyr votediversity.shp
Scripting syntax
About getting started with writing geoprocessing scripts
ClustersOutliersRendered_stats (Input_Feature_Class, Input_Field, Output_Layer_File, Output_Feature_Class)
| Parameter | Explanation | Data Type |
| Input_Feature_Class (Required) |
The feature class for which cluster analysis will be performed. |
Feature Layer |
| Input_Field (Required) |
The field to be evaluated. |
Field |
| Output_Layer_File (Required) |
The output layer file to store rendering information. You must include the .lyr extension as part of the file name. |
Layer File |
| Output_Feature_Class (Required) |
The output feature class to receive the results field and Z score. |
Feature Class |
Data types for geoprocessing tool parameters
Script example
# Perform cluster analysis for assault incidents
# Import system modules
import arcgisscripting
# Create the Geoprocessor object
gp = arcgisscripting.create()
# Local variables...
workspace = "c:/data"
input = "assaults.shp"
collect_output = "collect_output.shp"
collect_count_field = "Count"
cluster_output = "cluster_output.shp"
cluster_output_rendered = "cluster_output_rendered.lyr"
try:
# Set the current workspace (to avoid having to specify the full path to the feature classes each time)
gp.workspace = workspace
# Convert assault incidents into weighted point data
# Process: Collect Events...
gp.CollectEvents_stats(input, collect_output)
# Calculate Anselin Local Morans I statistic
# Process: Cluster/Outlier Analysis with Rendering...
gp.ClustersOutliersRendered(collect_output, collect_count_field, cluster_output_rendered, cluster_output)
except:
# If an error occurred when running the tool, print out the error message.
print gp.GetMessages()
Model
| Element | Explanation |
| Cluster and Outlier Analysis (Anselin Local Moran's I) |
Identifies areas of similarity (clusters of similar values) and outliers for a specified attribute field. Uses tool defaults: an inverse distance conceptualization of spatial relationships, Euclidean distance, and no standardization. |
| Z Score Rendering |
Renders Cluster and Outlier Analysis Z Scores results using a hot to cold rendering scheme. |