Tolerance Intervalshow to example data see also
Tolerance IntervalsStat > Quality Tools > Tolerance Intervals
Use to compute a range of values for a product's characteristic that likely covers a specified proportion of future product output. Alternatively, a lower or upper limit may be constructed such that the specified proportion will be greater than or less than the limit. Tolerance intervals specify both a population proportion and a confidence level. Manufacturers frequently use them to detect excessive variation by comparing client requirements to tolerance limits that cover an acceptable proportion of the population.
Minitab displays results using both the Normal and Nonparametric Methods. See Normal and nonparametric methods for tolerance intervals for more details. Minitab uses an exact method to calculate the normal tolerance intervals (see [6, 8, 9]).
One or more samples, each in a column: Choose if you entered raw data in columns. Enter the columns that contain the sample data. Minitab performs separate tolerance interval analyses on each column.
Summarized data: Choose if you have summary values for the sample size, mean, and standard deviation for one sample.
Sample size: Enter the value for the sample size.
Sample mean: Enter the value for the mean.
Standard deviation: Enter the value for the standard deviation.