Calculating the Standard and Directional Distributions of Features
Included in this tutorial:
Accessing the tools
The Standard Distance tool
Example 1: Standard Distance (unweighted)
Example 2: Standard Distance (weighted)
The Directional Distribution tool
Example 3: Directional Distribution (weighted)
Software version in examples: ArcGIS Pro 3.0.0.
Tutorial Data: The tutorial includes demonstration with sample data available here.
Credits: L. Meisterlin with Varisa Tanti and Nikolas Michael (2022)
This tutorial demonstrates using the Standard Distance tool to determine standard distribution (or standard distance) and the Directional Distribution tool to determine directional distribution (or distance) in ArcGIS Pro.
Accessing the tools
Measuring Geographic Distributions within Spatial Statistics Tools, with Directional Distribution and Standard Distance highlighted
Access either tool by clicking Geoprocessing toolbox in the main ribbon, and clicking Spatial Statistics Tools > Measuring Geographic Distributions >Standard Distance or Directional Distribution (Standard Deviation Ellipse).
You can also search for “Standard Distance” or “Directional Distribution” in the search bar.
the Standard Distance Tool
the inputs for running the Standard Distance geoprocessing tool
In the Standard Distance dialogue box, you will see these fields: Input Feature Class, Output Standard Distance Feature Class, Circle Size, Weighted Field, and Case Field.
Here’s a brief description of the different inputs:
Input Feature Class: Specify the feature class for which you will be calculating standard distance.
Output Standard Distance Feature Class: Specify the name and location of your standard distance feature class.
Circle Size: Specify the size of your circle in standard deviations from the mean center of the input features. You will be given the option of 1, 2, or 3 standard deviations.
Weight Field (optional): Designate the numeric field from the input feature class attribute table, with which to calculate the standard distribution. Leaving it empty will assign equal importance to all fields.
Case Field (optional): Designate the field from the input feature class attribute table with which to group features (and run multiple standard distance calculations—one per case). Leaving it empty will run one standard distance calculation on the whole dataset.
Example 1: Standard Distance Tool (unweighted)
example 1 inputs within the Standard Distance tool dialogue
This example uses the Standard Data Package from Tutorial Data to calculate one standard distribution, unweighted by any attributes.
The example results are output as a Standard Distance feature class circle.
In the output attribute table, you will find a field marked “StdDist.” This is your standard distance numeric value.
The attribute table also includes the coordinates of the mean center in fields labeled “CenterX” and “CenterY” in the CRS of the input feature class.
example 1 output Standard Distance circle
Example 2: Standard Distance Tool (weighted)
example 2 inputs within the Standard Distance Tool dialogue
This example uses the same dataset inputs as the previous example. Note that in this example, we are adding an input to the “Weight Field.” Here, we weight the point data based on values from the field “Int_lrg.”
Once again, the example results are output as a Standard Distance feature class circle.
In the output attribute table, you will find a field labeled “StdDist.” This is your standard distance numeric value.
Again, the attribute table also includes the coordinates of the circle’s center in the CRS of the input feature class.
example 2 output Standard Distance circle with attribute table
the Directional Distribution Tool
the Directional Distribution geoprocessing tool
In the Directional Distribution dialogue box, you will see these fields: Input Feature Class, Output Standard Distance Feature Class, Circle Size, Weight Field, and Case Field.
The inputs of the Directional Distribution tool are identical to the inputs of the Standard Distance tool (above).
The difference between the two tools is the shape of the output. Here, the tool generates a standard deviation ellipse rather than a circle.
Example 3: Directional Distribution Tool (weighted)
example 3 inputs within the Directional Distribution tool dialogue
This example uses the same data inputs as the previous two examples. Note that in this example, we again weight each input point based on the values in the “Int_lrg” field from the attribute table (just as we did in Example 2).
The example results are output as a Directional Distribution Feature Class ellipse.
In the attribute table, you will find a field labeled “XStdDist” and a field labeled “YStdDist.” These are your two Standard Distance numeric values (one per cardinal direction). Data that is evenly distributed directionally would yield similar values in both fields.
The attribute table also includes a field labeled “Rotation” with the direction of the ellipse’s major axis, as well as the coordinates of the ellipse’s center. Again, all units reflect the CRS of the input feature class.
Example 3 output Directional Distribution Ellipse with attribute table