Simple Random Sample Design

Simple random is a 3d initial sample design that relies on the generation of coordinate values to create the new samples. Samples are distributed randomly across the site and across all included vertical layers. Random sample designs are an underlying assumption in most statistical tests; however, samples may miss areas of interest and can occasionally be clustered. This sample design is useful for class III MARSSIM data.

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 Simple Random is selected during the Set sampling parameters step, the Parameters Window changes to look like the following:

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See Design Core samples or Show Ghost Image for an explanation of the core vs. single point sampling options.

If there are polygons, new samples will only be placed inside the active polygons.

Under Number of Samples, select the appropriate method. See Determining the Number of Samples for more information.

Under Random Seed, enter a number to generate the same random design. If the random seed is blank, SADA will generate a distinct random design each time.

Press Show the Results on the Steps Window and SADA will display the sample locations in the Graphics Window.

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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.