Quality & Quantity

, Volume 43, Issue 4, pp 661–668 | Cite as

Yield measure for the process with multiple streams

Research Note


Process capability indices, such as C pk , have been widely used in the manufacturing industry to provide common quantitative measures for process performance. The index C pk only provides an approximate rather than an exact measure of the process yield. To obtain an exact measure of the process yield, Boyles proposed a yield index S pk . Capability measures for processes with single stream have been investigated extensively; however, multiple streams processes often occur in practice. Bothe presented a capability index for multiple streams process. In the present paper, a new index \(S_{pk}^M \) that is able to provide an exact measure of yield for a multiple streams process is developed. Three examples are given for illustration. From the results of the yield measure in the three examples, the conventional approach, using the arithmetic average of the estimated yield indices of all streams, will certainly over-estimate the process yield.


Process capability index Process yield index Multiple streams process 


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Department of Business AdministrationTransworld Institute of TechnologyTouliuTaiwan, ROC
  2. 2.Department of Industrial Engineering and ManagementNational Yunlin University of Science and TechnologyTouliuTaiwan, ROC
  3. 3.Department of FinanceNational Taichung Institute of TechnologyTaichungTaiwan, ROC

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