Abstract
The control chart based on mean deviation (MD) is customary used as a robust alternative to the existing Shewhart control charts for observing changes in dispersion parameter of the process. The existing model of MD control chart is rooted under the assumption that indeterminate observations are not included in measured quality characteristic. If, inspected quality data entail some indeterminate and vague information, typical design of the MD control chart could not be effectively employed. This study originally presents an appropriate generalized design namely neutrosophic mean deviation ( \widetilde {\text {MD}} ) control chart that could accommodate imprecise observations in collected quality characteristic variables. Under the neutrosophic situation, the related properties of this newly \widetilde {\text {MD}} design have been derived. Using simulated data, performance of the \widetilde {\text {MD}} control chart in terms of neutrosophic average run length ( \widetilde {\text {ARL}} ) is investigated. The performance of proposed \widetilde {\text {MD}} control chart relative to existing competitor designs has been evaluated. The study reveals that proposed design of \widetilde {\text {MD}} chart outperforms as to existing counterparts in terms of statistical power. To illustrate the efficacy of this new design, real data from a manufacturing company has been used to describe the control procedure of the proposed \widetilde {\text {MD}} control chart.