Beyond analyzing spatial patterns, GIS analysis can be used to examine or quantify relationships among features. The Modeling Spatial Relationships tools construct spatial weights matrices or model spatial relationships using regression analyses.
Tools that construct spatial weights matrix files
measure how features in a data set relate to each other in space. A spatial weights matrix is a representation of the spatial structure of your data: the spatial relationships that exist among the features in your dataset. True spatial statistics integrate information about spatial relationships into their mathematics. Some of the tools that may use a spatial weights matrix file are Spatial Autocorrelation (Morans I)
, Cluster and Outlier Analysis: Anselin Local Moran's I
, and Hot Spot Analysis (Getis-Ord Gi*)
The regression tools provided in the Spatial Statistics Toolbox model relationships among data variables associated with geographic features, allowing you to make predictions for unknown values or to better understand key factors influencing a variable you are trying to model. Regression methods allow you to verify relationships and to measure how strong those relationships are.
The following table lists the tools available and provides a brief description of each.
NOTE: Tool availability is determined by ArcGIS license. Licensing requirements for each tool are listed below.
|Generate Network Spatial Weights
||Builds a spatial weights matrix file specifying spatial relationships among features in a feature class based on a Network dataset. Available with any ArcGIS license. Requires the Network Analyst Extension.
|Generate Spatial Weights Matrix
||Builds a spatial weights matrix file specifying spatial relationships among features in a feature class. Available with any ArcGIS license.
|Geographically Weighted Regression
||A local form of linear regression used to model spatially varying relationships among a set of data variables. Requires an ArcInfo license or the Geostatistical Analyst extension or the Spatial Analyst extension.
|Ordinary Least Squares
||Performs global linear regression to model the relationships among a set of data variables. Requires an ArcInfo license or the Spatial Analyst extension.
NOTE: If you don't have the ArcInfo license but do have the Spatial Analyst Extension, right click ArcToolbox and uncheck the Hide Locked Tools option. OLS will appear with the lock symbol, but will operate correctly.