A study on the S2-EWMA chart for monitoring the process variance based on the MRL performance
The existing optimal design of the fixed sampling interval S2-EWMA control chart to monitor the sample variance of a process is based on the average run length (ARL) criterion. Since the shape of the run length distribution changes with the magnitude of the shift in the variance, the median run leng...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Universiti Kebangsaan Malaysia
2015
|
| Online Access: | http://journalarticle.ukm.my/8993/ http://journalarticle.ukm.my/8993/1/20_Teh_Sin_Yin.pdf |
| _version_ | 1848811950663794688 |
|---|---|
| author | Teh, Sin Yin Khoo, Michael Boon Chong Ong, Ker Hsin Soh, Keng Lin Teoh, Wei Lin |
| author_facet | Teh, Sin Yin Khoo, Michael Boon Chong Ong, Ker Hsin Soh, Keng Lin Teoh, Wei Lin |
| author_sort | Teh, Sin Yin |
| building | UKM Institutional Repository |
| collection | Online Access |
| description | The existing optimal design of the fixed sampling interval S2-EWMA control chart to monitor the sample variance of a process is based on the average run length (ARL) criterion. Since the shape of the run length distribution changes with the magnitude of the shift in the variance, the median run length (MRL) gives a more meaningful explanation about the in-control and out-of-control performances of a control chart. This paper proposes the optimal design of the S2-EWMA chart, based on the MRL. The Markov chain technique is employed to compute the MRLs. The performances of the S2-EWMA chart, double sampling (DS) S2 chart and S chart are evaluated and compared. The MRL results indicated that the S2-EWMA chart gives better performance for detecting small and moderate variance shifts, while maintaining almost the same sensitivity as the DS S2 and S charts toward large variance shifts, especially when the sample size increases. |
| first_indexed | 2025-11-14T23:54:33Z |
| format | Article |
| id | oai:generic.eprints.org:8993 |
| institution | Universiti Kebangasaan Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T23:54:33Z |
| publishDate | 2015 |
| publisher | Universiti Kebangsaan Malaysia |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | oai:generic.eprints.org:89932016-12-14T06:48:39Z http://journalarticle.ukm.my/8993/ A study on the S2-EWMA chart for monitoring the process variance based on the MRL performance Teh, Sin Yin Khoo, Michael Boon Chong Ong, Ker Hsin Soh, Keng Lin Teoh, Wei Lin The existing optimal design of the fixed sampling interval S2-EWMA control chart to monitor the sample variance of a process is based on the average run length (ARL) criterion. Since the shape of the run length distribution changes with the magnitude of the shift in the variance, the median run length (MRL) gives a more meaningful explanation about the in-control and out-of-control performances of a control chart. This paper proposes the optimal design of the S2-EWMA chart, based on the MRL. The Markov chain technique is employed to compute the MRLs. The performances of the S2-EWMA chart, double sampling (DS) S2 chart and S chart are evaluated and compared. The MRL results indicated that the S2-EWMA chart gives better performance for detecting small and moderate variance shifts, while maintaining almost the same sensitivity as the DS S2 and S charts toward large variance shifts, especially when the sample size increases. Universiti Kebangsaan Malaysia 2015-07 Article PeerReviewed application/pdf en http://journalarticle.ukm.my/8993/1/20_Teh_Sin_Yin.pdf Teh, Sin Yin and Khoo, Michael Boon Chong and Ong, Ker Hsin and Soh, Keng Lin and Teoh, Wei Lin (2015) A study on the S2-EWMA chart for monitoring the process variance based on the MRL performance. Sains Malaysiana, 44 (7). pp. 1067-1075. ISSN 0126-6039 http://www.ukm.my/jsm/malay_journals/jilid44bil7_2015/KandunganJilid44Bil7_2015.html |
| spellingShingle | Teh, Sin Yin Khoo, Michael Boon Chong Ong, Ker Hsin Soh, Keng Lin Teoh, Wei Lin A study on the S2-EWMA chart for monitoring the process variance based on the MRL performance |
| title | A study on the S2-EWMA chart for monitoring the process variance
based on the MRL performance |
| title_full | A study on the S2-EWMA chart for monitoring the process variance
based on the MRL performance |
| title_fullStr | A study on the S2-EWMA chart for monitoring the process variance
based on the MRL performance |
| title_full_unstemmed | A study on the S2-EWMA chart for monitoring the process variance
based on the MRL performance |
| title_short | A study on the S2-EWMA chart for monitoring the process variance
based on the MRL performance |
| title_sort | study on the s2-ewma chart for monitoring the process variance
based on the mrl performance |
| url | http://journalarticle.ukm.my/8993/ http://journalarticle.ukm.my/8993/ http://journalarticle.ukm.my/8993/1/20_Teh_Sin_Yin.pdf |