Multivariate Process Capability Assessment for Non-normal Quality Data

Determination of the performance capability of a stable process using the standard process capability indices such as and requires that the underlying data follow a normal distribution. However it is an undisputed fact that real processes very often produce non-normal quality characteristics data and also these quality characteristics are very often correlated with each other. For such non-normal and correlated multivariate quality characteristics, application of standard capability measures using conventional methods can lead to erroneous results. This research study presents several capability assessment methods to estimate more precisely and accurately process performances based on univariate as well as multivariate quality characteristics. The proposed capability assessment methods also take into account the correlation, variance and covariance as well as non-normality issues of the quality characteristics data.

Autorentext

Shafiq Ahmad é MPhil em Microbiologia Clínica e Imunologia. Cresceu em Teroona, Lower Dir, uma área remota de KPK. Obteve o seu mestrado em Microbiologia na FUUAST Karachi e agora está a fazer o seu doutoramento em Microbiologia na Universidade de Haripur, KPK. Tem uma publicação internacional e duas apresentações de posters em conferências internacionais.