Sampling Plans Results - Fixed Sampling Plan Tab

Select the Fixed Sampling Plan tab of the Sampling Plans Results dialog box to access the options described here.

Summary: Results for fixed sampling plans
Click the Summary: Results for fixed sampling plans button to create a spreadsheet that summarizes the results for the fixed sampling plan, including the expected sample size and the upper and/or lower confidence limits for the H0 mean. Note that the results in this spreadsheet will reflect the sample size (N) as shown next to the option Sample size (see below). Thus, after changing the sample size via that option, the results in this spreadsheet will also change.
Sample size
Click this button to display the Specify Sample Size dialog box, in which you specify a Sample size, and compute from it the resultant Beta error probability (probability of not detecting a "bad" batch). To see the resultant confidence limits for the mean under H0, click the Results for fixed sampling plans button (see above).
Operating characteristic curve
Click the Operating characteristic curve button to produce a plot showing the operating characteristic curve. The operating characteristic curve is discussed in the Introductory Overview. In general, this plot specifies the power of the fixed sampling plan, that is, the probability of rejecting samples from populations with a true mean as indicated on the x-axis. Note that this probability is identical to 1-β (the beta error probability). Also included in the plot (as dashed lines) are the power curves for similar smaller and larger sample sizes. Note that in extreme cases, when the respective power curves require that the normal probability functions be evaluated in the extreme margins of the distribution, it can happen that some power curves may not appear smooth, but rather like step-functions. Even though all probability computations in STATISTICA are performed with the highest precision, this is the result of unavoidable loss of precision in the extreme probability computations.