Abstract
In this paper, we consider the interval estimation problem on the process capability indices in general random effect model with balanced data. The confidence intervals for three commonly used process capability indices are developed by using the concept of generalized confidence interval. Furthermore, some simulation results on the coverage probability and expected value of the generalized lower confidence limits are reported. The simulation results indicate that the proposed confidence intervals do provide quite satisfactory coverage probabilities.
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References
Bissell AF (1990) How reliable is your capability index?. Appl Stat 39: 331–340
Boyles RA (1994) Process capability with asymmetric tolerances. Commun Stat Simulation Comput 23: 613–643
Chou YM, Owen DB, Borrego ASA (1990) Lower confidence limits on process capability indices. J Qual Technol 22: 223–229
Franklin LA, Wasserman GS (1991) Bootstrap confidence interval estimates of C pk : an introduction. Commun Stat Simulation Comput 20: 231–242
Franklin LA, Wasserman GS (1992) A note on the conservative nature of the tables of lower confidence limits for C pk with a suggested correction. Commun Stat Simulation Comput 21: 1165–1169
Gamage J, Mathew T, Weerahandi S (2004) Generalized p-values and generalized confidence regions for the multivariate Behrens-Fisher problem and MANOVA. J Multivariate Anal 88: 177–189
Gilder K, Ting N, Tian L, Cappelleri JC, Hanumara RC (2007) Confidence intervals on intraclass correlation coefficients in a balanced two-factor random design. J Stat Plann Inference 137: 1199–1212
Kane VE (1986) Process capability indices. J Qual Technol 18: 41–52
Kotz S, Johnson NL (1993) Process capability indices. Chapman and Hall, London
Kotz S, Johnson NL (2002) Process capability indices—a review, 1992-2000. J Qual Technol 34: 2–19
Kotz S, Lovelace CR (1998) Process capability indices in theory and practice. Arnold, London
Krishnamoorthy K, Guo HZ (2005) Assessing ocupational exposure via the one-way random effects model with unbalanced data. J Stat Plann Inference 128: 219–229
Krishnamoorthy K, Lu Y (2003) Inferences on the common mean of several normal populations based on the generalized variable method. Biometrics 59: 237–247
Kurian KM, Mathew T, Sebastian G (2008) Generalized confidence intervals for process capability indices in the one-way random model. Metrika 67: 83–92
Kushler RH, Hurley P (1992) Confidence bounds for capability indices. J Qual Technol 24: 188–196
Liao CT, Lin TY, Iyer HK (2005) One- and two-sided tolerance interals for general balanced mixed models and unbalanced one-way random models. Technometrics 47: 323–335
Lin GH, Pearn WL, Yang YS (2005) A Bayesian approach to obtain a lower bound for the C pm capability index. Qual Reliab Eng Int 21: 655–668
Mathew T, Webb DW (2005) Generalized p values and confidence intervals for variance components: applications to army test and evaluation. Technometrics 47: 312–322
Mathew T, Sebastian G, Kurian KM (2007) Generalized confidence intervals for process capability indices. Qual Reliab Eng Int 23: 471–481
Nagata Y, Nagahata H (1992) Approximation formulas for the confidence intervals of process capability indices. Okayama Econ Rev 25: 301–314
Pearn WL, Liao MY (2006) One sided process capability assessment in the presence of measurement errors. Qual Reliab Eng Int 22: 771–785
Pearn WL, Lin PC, Chen KS (2004) The C pk ′′ index for asymmetric tolerances: implications and inference. Metrika 60: 119–136
Perakis M, Xekalaki E (2004) A new method for constructing confidence intervals for the index C pm . Qual Reliab Eng Int 20: 651–655
Roy A, Mathew T (2005) A generalized confidence limit for the reliability function of a two-parameter exponential distribution. J Stat Plann Inference 128: 509–517
Spiring F, Leung B, Cheng S, Yeung A (2003) A bibliography of process capability papers. Qual Reliab Eng Int 19: 445–460
Tian L, Cappelleri JC (2004) A new approach for interval estimation and hypothesis testing of a certain intraclass correlation coefficient: the generalized variable method. Stat Med 23: 2125–2135
Vännman K (1997) A general class of capability indices in the case of asymmetric tolerances. Commun Stat Theory Meth 26: 2049–2072
Vännman K (1998) Families of capability indices for one-sided specification limits. Statistics 31: 43–66
Wang SG, Chow SC (1994) Advanced linear model. Marcel Dekker, New York
Weerahandi S (1993) Generalized confidence intervals. J Am Stat Assoc 88: 899–905
Weerahandi S (1995) Exact statistical methods for data analysis. Springer, New York
Weerahandi S (2004) Generalized inference in repeated measures. Wiley, New York
Wu CW, Pearn WL (2005) Capability testing based on C pm with multiple samples. Qual Reliab Eng Int 21: 29–42
Wu MX (2004) Theory and methods of estimation in mixed effects models. Beijing University of Technology, Doctor’s thesis, Beijing
Wu MX, Wang SG (2005) A new spectral decomposition for the covariance matrix in linear mixed model and its applications. Sci China (Ser A) 35: 947–960
Ye RD, Wang SG (2007) Generalized p-values and generalized confidence intervals for variance components in general random effect model with balanced data. J Syst Sci Complexity 20: 572–584
Ye RD, Wang SG (2008) Generalized inferences on the common mean in MANOVA models. Commun Stat Theory Meth 37: 2291–2303
Ye RD, Wang SG (2009a) Inferences on the intraclass correlation coefficients in the unbalanced two-way random effects model with interaction. J Stat Plann Inference 139: 396–410
Ye RD, Wang SG (2009b) Assessing occupational exposure via the unbalanced one-way random effects model. Commun Stat Simulation Comput 38: 308–317
Zhang NF, Stenback GA, Wardrop DM (1990) Interval estimation of process capability index C pk . Commun Stat Theory Meth 19: 4455–4470
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Ye, R., Ma, T. & Wang, S. Generalized confidence intervals for the process capability indices in general random effect model with balanced data. Stat Papers 52, 153–169 (2011). https://doi.org/10.1007/s00362-009-0216-x
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DOI: https://doi.org/10.1007/s00362-009-0216-x