Hot Spot: Minimize Sample Size By Hot Spot Definition

With Hot Spot: Minimize Sample Size by Hot Spot Definition, the user defines the grid style and the probability of hitting a hot spot of a given size, shape, and orientation. This combination yields a possible sample number, and grid definition.

Availability

This sample design is available for all SADA files.

Steps

These are the steps that display in the Steps Window when this sample design is selected during the step Set sampling parameters. Click on the links below for more details about the following steps.

1. See the data, Draw/Edit Prior, Display empty plot

2. Set up the site

3. Set GIS overlays

4. Set sampling parameters

5. Show the results

6. Import sampled data

7. Format picture

8. Auto-document

9. Add to results gallery (not available for empty SADA files)

Design-specific Parameters

When Hot Spot: Minimize Sample Size by Hot Spot Definition is selected during the Set sampling parameters step, the Parameters Window changes to look like the following:

image\v4ht0413.gif

Under Grid Definition, select a square, triangle, or rectangle grid style.

Enter the parameters for Shape Definition. For Hot Spot Shape, enter a value that is greater than or equal to .2 and less than or equal to 1. This is the ratio between the major and minor axes of the elliptical hot spot. (Note that 1 is a circle.) For Hot Spot Orientation, select Random to use omni directional ellipses, or select Degrees and enter a value between 0 and 90.

Define the Hot Spot Definition by setting either the area or the length of the semi-major axis (note that the other value will change accordingly), and enter a value between 1 and 100 for the Probability.

Press Show the Results and SADA will determine the number of new samples and the grid design and display the sample locations in the Graphics Window. SADA will also enter the resulting grid size information on the Parameters Window. If there are polygons, new samples will only be placed inside the active polygons.

image\v4ht0414.gif

To view the actual coordinates of the new sample points export the information to a comma delimited excel file by using the Output to File toolbar button in main form of SADA.