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How is the neighborhood processing for focal statistics?
To illustrate the neighborhood processing for Focal Statistics calculating a Sum statistic, consider the processing cell with a value of 5 in the following diagram. A rectangular 3 by 3 cell neighborhood shape is specified.
Which is an example of a focal statistic?
The output focal statistics raster. This example calculates the least-frequently occuring value in a ring-shaped neighborhood around each cell in the input raster. This example determines the least frequently occurring value in a 10-by-10 neighborhood around each cell in the input raster.
When do you use nodata in focal statistics?
NODATA —Specifies that if any cell in a neighborhood has a value of NoData, the output for the processing cell will be NoData. With this option, the presence of a NoData value implies that there is insufficient information to determine the statistic value for the neighborhood. The output focal statistics raster.
How does the focal statistics tool work in ArcGIS?
The Focal Statistics tool performs a neighborhood operation that computes an output raster where the value for each output cell is a function of the values of all the input cells that are in a specified neighborhood around that location.
What are the different types of focal statistics?
The possible statistics that can be calculated within a neighborhood are mean, majority, maximum, median, minimum, minority, range, standard deviation, sum, and variety. The Focal Statistics tool gives control over the neighborhood type and statistic to be calculated.
How is the average nearest neighbor statistic expressed?
For the Average Nearest Neighbor statistic, the null hypothesis states that features are randomly distributed. The Nearest Neighbor Index is expressed as the ratio of the Observed Mean Distance to the Expected Mean Distance.
Do you need to have a neighbor definition for focal operation?
The focal operation does not need to be restricted to a pre-defined list of neighbor definitions, for example, you might want to exclude central cells from the output (i.e. the 3×3 neighbor would consist of 8 input pixels instead of 9). To customize the neighborhood definition, you need to create an ASCII text file.
How to find the average nearest neighbor in Excel?
The Average Nearest Neighbor tool returns five values: Observed Mean Distance, Expected Mean Distance, Nearest Neighbor Index, z-score, and p-value. These values are accessible from the Results window and are also passed as derived output values for potential use in models or scripts.