Application of Control Charting to Weibull Data Mini Paper Taken from the Winter 1992 Newsletter
Abstract: To determine if the quality characteristics that are described by a Weibull probability model in a lot type process is in control, standard normal theory statistical process control charting techniques can be applied to the maximum likelihood estimated characteristic life and shape parameters. The caveat is that normality should be checked to give assurance that the lot size is sufficiently large. The T2 control chart is useful to consider because of the correlation which exists between the characteristic life and shape parameters.
Keywords: Weibull distribution - Statistical process control - Maximum likelihood estimation - Normal distribution - Joint density function - Control charts - Sample Size - Normal plots - Wilk-Shapiro test - Moving range chat - Hotelling's T2 distribution - Correlation