Capability Analysis (Normal Distribution) - Options
main topic     see also 

Stat > Quality Tools > Capability Analysis > Normal > Options

You can specify a process target, or nominal specification. Minitab then calculates Cpm in addition to the standard capability statistics. You can also choose how the capability analysis is displayed and what statistics are calculated.

You can set preferences for the sigma tolerance for capability statistics and the display of either the capability statistics or the benchmark Z statistics using Tools > Options > Control Charts and Quality Tools > Capability analysis.

Dialog box items

Target (adds Cpm to table): Enter a number that Minitab uses as a target. Minitab then calculates Cpm, in addition to the standard capability statistics, displaying the target and Cpm values in a table below the graph.

Use tolerance of K*sigma for capability statistics K= Enter a number (default is 6.0) to calculate the capability statistics using an interval other than 6 standard deviations wide (3 on each side of the process mean). Minitab interprets this value as a two-sided tolerance. If you want to use a one-sided tolerance, enter a two-sided tolerance value that is twice that of your one-sided tolerance. For example, if you want a one-sided tolerance of 3 sigma, enter 6.

Perform Analysis

Within subgroup analysis: Check to perform the within-subgroup analysis only. The default is to perform both the within-subgroup and overall analyses.

Overall analysis: Check to perform the overall analysis only. The default is to perform both the within-subgroup and overall analyses.

Note

The Perform Analysis options are ignored with a Johnson transformation.

Display

Parts per million: Choose to display the expected and observed out-of-spec in parts per million.

Percents: Choose to display the expected and observed out-of-spec in percents..

Capability stats (Cp, Pp): Choose to display capability statistics.

Benchmark Z's: Choose to display benchmark Z statistics.

Include confidence intervals: Check to display confidence intervals for Cp, Cpk, Pp, and Ppk.

Confidence level: Enter a confidence level between 0 and 100 (default is 95.0).

Confidence intervals: Choose to display two-sided confidence intervals (the default) or just an upper or lower confidence bound.

Title: Type a new title to replace the default title.