Determining the Number of Samples

There are three ways to define the number of new samples: user definition, sign test, and Wilcoxon rank sum test.

Select Develop sample design from the interview list, Set sampling parameters from the Steps Window, and the applicable sample design in the Parameters Window. Select the appropriate method for determining number of samples in the Parameters Window (for most sample designs).

For user definition, select the You pick radio button. Then enter the number of desired samples in the text box. SADA will determine that number of new samples for the selected sample design and show their locations in the Graphics Window.

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Based on Sign Test uses the non-parametric Sign test to determine sample size with the following user inputs: DCGL, LBGR, and acceptable Type I and II error rates. This method is appropriate for grid designs, simple random sampling, and when no background is available.

Based on Wilcoxon Rank Sum uses the non-parametric Wilcoxon Rank Sum test to determine sample size with the following user inputs: DCGL, LBGR, and acceptable Type I and II error rates. This method is appropriate for grid designs, simple random sampling, and when no background is available.