The process capability index, Cpk, is extensively used to assess process performance in manufacturing industry. Statistical hypothesis testing or an interval estimation of a single Cpk had been derived under a normally distributed process. However, the difference between two process capability indices, Cpk1 - Cpk2, cannot be inferred statistically because of the complexity of the sampling probability theory. This study proposes a bootstrap resampling simulation method to construct the biased corrected percentile bootstrap (BCPB) confidence interval of (Cpk1 - Cpk2), which can be used to select the better of two suppliers. The various simulation results indicate that the bootstrap confidence interval of (Cpk1 - Cpk2) can be employed to evaluate effectively the difference between the performance of two suppliers.
|Number of pages||8|
|Journal||International Journal of Advanced Manufacturing Technology|
|State||Published - 10 May 2003|
- Bootstrap method
- Interval estimation
- Process capability index
- Sensitivity analysis