A spatial weights matrix quantifies the spatial relationships that exist among the features in your dataset. Various tools in the Spatial Statistics toolbox and Space Time Pattern Mining toolbox perform analysis using neighboring features. The spatial weights matrix file defines those neighbor spatial relationships. For more information about spatial weights, see Modeling spatial relationships.
Typically, spatial relationships among a set of features are based on Euclidean distance and use contiguity, fixed distance, or inverse distance weighting schemes. However, for many applications such as retail analysis, accessibility to services, emergency response, evacuation planning, and traffic incident analyses, it is more appropriate to define spatial relationships using real-world travel networks such as roads, railways, and footpaths. The Generate Network Spatial Weights tool allows you to model and store spatial relationships based on time, distance, or cost between point features when travel is restricted to a network dataset. This tool requires a license for the ArcGIS Network Analyst extension.
The network dataset can come from any of the following sources:
- A network dataset saved on a local drive or network. If your organization maintains its own street network datasets, you may already have access.
- Logistic and routing services hosted in ArcGIS Online or ArcGIS Enterprise. If you perform an analysis using ArcGIS Online, the solver references a high-quality, worldwide network dataset stored in the ArcGIS Online cloud and consumes ArcGIS Online credits.
- Configured network datasets provided by ArcGIS StreetMap Premium. These network datasets are in SDC format and include North America, Latin America, Europe, the Middle East, Africa, Japan, Australia, and New Zealand.
Using the input point features located on the network, the neighbors and associated spatial weights are determined for each input feature based on minimizing distance, time, or cost using the travel mode of the network data source.
Additional resources
Anselin, L. (1988). Spatial Econometrics: Methods and Models. Boston: Kluwer.
Getis, A., and Aldstadt, J. (2004). "Constructing the Spatial Weights Matrix Using a Local Statistic." Geographical Analysis 36(2):90–104.
Haining, R. (2003). Spatial Data Analysis: Theory and Practice. Cambridge, UK: Cambridge University Press.
Price, Mike. (Fall 2009). "It's All about Streets". ArcUser Online. ESRI.