TY - JOUR
T1 - A two-sided SPRT control chart for process dispersion
AU - Mahadik, Shashibhushan B.
AU - Godase, Dadasaheb G.
AU - Teoh, W. L.
N1 - Funding Information:
Shashibhushan B. Mahadik's work was supported in part by Shivaji University, Kolhapur through Research Strengthening Scheme (SU/C&U.D.Section/2/13/9). Dadasaheb G. Godase's work was supported by Department of Science and Technology through INSPIRE fellowship (IF160684). The authors are grateful to the reviewer for his/her critical comments and suggestions that have greatly improved the contents of the paper.
Publisher Copyright:
© 2021 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2021
Y1 - 2021
N2 - This paper proposes a two-sided sequential probability ratio test chart for monitoring dispersion of a normally distributed process. Accurate approximate expressions that relate the statistical performance measures of this chart to that of its corresponding one-sided charts are obtained through simulations. An approach to design the chart having the specified in-control performance and the optimal out-of-control performances for detecting the particular upper and lower shifts that are desired to detect as efficiently as possible is provided. It is found through numerical comparisons that the overall statistical performance of the proposed chart is superior to that of the competitor charts in the existing literature. The application of the chart is illustrated through real-data on the thickness of dielectric polyimide coating layer that is applied on a wafer used in an integrated circuit.
AB - This paper proposes a two-sided sequential probability ratio test chart for monitoring dispersion of a normally distributed process. Accurate approximate expressions that relate the statistical performance measures of this chart to that of its corresponding one-sided charts are obtained through simulations. An approach to design the chart having the specified in-control performance and the optimal out-of-control performances for detecting the particular upper and lower shifts that are desired to detect as efficiently as possible is provided. It is found through numerical comparisons that the overall statistical performance of the proposed chart is superior to that of the competitor charts in the existing literature. The application of the chart is illustrated through real-data on the thickness of dielectric polyimide coating layer that is applied on a wafer used in an integrated circuit.
KW - average number of observations to signal
KW - Average number of samples to signal
KW - parametric control chart
KW - statistical process control
UR - http://www.scopus.com/inward/record.url?scp=85109334144&partnerID=8YFLogxK
U2 - 10.1080/00949655.2021.1943667
DO - 10.1080/00949655.2021.1943667
M3 - Article
AN - SCOPUS:85109334144
SN - 0094-9655
VL - 91
SP - 3603
EP - 3614
JO - Journal of Statistical Computation and Simulation
JF - Journal of Statistical Computation and Simulation
IS - 17
ER -