On the choice of a capability index for asymmetric tolerances
نویسنده
چکیده
For a process normally distributed and a target located at the mid-point of a twosided tolerance interval, Vännman suggests a family of indices depending on two parameters. In order to choose the parameters which allow to obtain an index that is sensitive to departures of the mean from the target, we need to take the properties of its estimator into account. For a target not located at the mid-point of the interval of tolerance, Chen and Pearn suggest a family of indices generalizing Vännman’s. The moments of these indices are given, then their expected values and mean square errors are studied to choose an index that is sensitive to the deviations of the mean from the target.
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