Abstract
Practitioners of industrial statistics are generally familiar with the common C p and C pk process capability indices. However, many additional indices have been proposed, and knowledge of these is less widespread. More importantly, information regarding the indices' comparative behavior is lacking. This paper compares the behavior of various indices under shifting process conditions. Both useful and misleading characteristics of the indices are identified. We begin with a short history of process capability measures. Several process capability indices are reviewed. Application areas for capability indices are also summarized. The indices are grouped according to the loss functions which are used in their interpretation. Characteristics of the various indices are discussed. Finally, recommendations are made for selection of indices at differing levels of process performance.
Similar content being viewed by others
References
L.K. Chan, S.W. Cheng and F.A. Spiring, The robustness of process capability index C p to departures from normality, in: Statistical Theory and Data Analysis, II, ed. K. Matusita, North-Holland, Amsterdam, 1988, pp. 223-229.
L.K. Chan, S.W. Cheng and F.A. Spiring, A new measure of process capability: C pm, Journal of Modeling and Simulation 11(1988)1-6.
J.A. Clements, Process capability calculations for non-normal distributions, Quality Progress 22(9)(1989)95-100.
A.V. Feigenbaum, Quality Control, McGraw-Hill, New York, 1951, pp. 383-389.
F.M. Gryna, Quality Control Handbook, ed. J.M. Juran, McGraw-Hill, New York, 1988, pp. 16.14-16.35, 4th ed.
J.T. Herman, Capability index — enough for process industries?, ASQC Annual Quality Congress Transactions, Toronto, 1989, pp. 670-675.
T.C. Hsiang and G. Taguchi, A tutorial on quality control and assurance — the Taguchi methods, unpublished presentation given at the Annual Meetings of the American Statistical Association, Las Vegas, NV, 1985.
W.G. Hunter and C.P. Kartha, Determining the most profitable target value for a production process, Journal of Quality Technology 9(1977)176-181.
N.L. Johnson, S. Kotz and W.L. Pearn, Flexible process capability indices, Institute of Statistics Mimeo Series, No. 2072, Department of Statistics, University of North Carolina, Chapel Hill, NC, 1992.
J.M. Juran, Quality Control Handbook, McGraw-Hill, New York, 1951, pp. 253-279 and 404-409.
J.M. Juran, Quality Control Handbook, 2nd ed., McGraw-Hill, New York, 1962, pp. 11-14-11-27
J.M. Juran and P.M. Gryna, Quality Planning and Analysis, 2nd ed., McGraw-Hill, New York, 1980, pp. 283-295.
V.E. Kane, Process capability indices, Journal of Quality Technology 18(1986)41-52.
S. Kotz and N.J. Johnson, Process Capability Indices, Chapman and Hall, London, 1993, pp. 121-127.
L.S. Nelson, Best target value for a production process, Journal of Quality Technology 10(1978)88-89.
W.L. Pearn, S. Kotz and N.L. Johnson, Distributional and inferential properties of process control indices, Journal of Quality Technology 24(1992)216-231.
R.N. Rodriguez, Recent developments in process capability analysis, Journal of Quality Technology 24(1992)176-187.
W.A. Shewhart, Economic Control of Quality of Manufactured Products, D. Van Nostrand, New York, 1931, pp. 249-272.
C.H. Springer, A method for determining the most economical position of a process mean, Industrial Quality Control 8(1951)36-39.
L.P. Sullivan, Reducing variability: A new approach to quality, Quality Progress 17(7)(1984)15-21.
L.P. Sullivan, Letters, Quality Progress 18(4)(1985)7-8.
Rights and permissions
About this article
Cite this article
Palmer, K., Tsui, KL. A review and interpretations of process capability indices. Annals of Operations Research 87, 31–47 (1999). https://doi.org/10.1023/A:1018993221702
Issue Date:
DOI: https://doi.org/10.1023/A:1018993221702