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One-sample variance test simulation

Chi-Square Test for One Variance

Minitab does not have a Chi-Square test for a single variance, although it has always has confidence intervals for the standard deviation (which is similar) as part of the graphical summary.

One of the primary uses for Minitab macros is to create an analysis that is not part of Minitab. Here is an example of a macro for testing a single variance against a standard. The analysis uses the Chi-Square test. It shows the hypotheses, test statistic, p value, and the conclusion you should draw from the test. It also includes confidence intervals for the variance and standard deviation, illustrating where the variance standard lies relative to the confidence intervals. The macro lets you enter the standard, the sample data, choose the type of hypothesis (>, <, <>), and the confidence level.

The last part of the analysis is a set of graphs for evaluating the normality of the data. This test is not very robust, so there is a caution letting you know what to do if the data are not reasonably normal.

For details on the robustness of the test, see the one-sample variance test simulation

One-sample t test simulation
Wilcoxon test simulation
One-Variance Test
Descriptive Statistics