Robust Estimator Based X ? Control Chart for Specified Capability Index Cpk

Authors(2) :-J. Livingston Thiraviya Kumar, S. Devaraj Arumainayagam

Statistical process Control is a tool used to improve the quality of a product by achieving process capability. Control Charts are used to confirm whether the process is statistically control. In general process performance is measured through the four basic process capability indices Cp, Cpk, Cpm and Cpmk. To calculate the basic capability indices, it is assumed that the quality characteristics follow normal distribution. In practice most of the key quality characteristics fails normality. MAD based capability index is an alternative for heavily skewed data. In this paper, a robust X ? chart for a specified capability index is proposed. The proposed control chart and basic Shewhart control chart are compared using a simulated process data from normal distribution.

Authors and Affiliations

J. Livingston Thiraviya Kumar
Department of Economics and Statistics, Government of TamilNadu, India.
S. Devaraj Arumainayagam
Department of Statistics, Govt. Arts College, Coimbatore, Tamil Nadu, India

Capability indices, Median Absolute Deviation, Control chart, Normal Distribution.

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Publication Details

Published in : Volume 4 | Issue 1 | January-February 2018
Date of Publication : 2018-02-28
License:  This work is licensed under a Creative Commons Attribution 4.0 International License.
Page(s) : 785-790
Manuscript Number : IJSRSET1841192
Publisher : Technoscience Academy

Print ISSN : 2395-1990, Online ISSN : 2394-4099

Cite This Article :

J. Livingston Thiraviya Kumar, S. Devaraj Arumainayagam, " Robust Estimator Based X ? Control Chart for Specified Capability Index Cpk, International Journal of Scientific Research in Science, Engineering and Technology(IJSRSET), Print ISSN : 2395-1990, Online ISSN : 2394-4099, Volume 4, Issue 1, pp.785-790, January-February-2018.
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