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Full-Text Articles in Physical Sciences and Mathematics
Poisson Distributed Individuals Control Charts With Optimal Limits, Negin Enayaty Ahangar
Poisson Distributed Individuals Control Charts With Optimal Limits, Negin Enayaty Ahangar
Graduate Theses and Dissertations
The conventional method used in attribute control charts is the Shewhart three sigma limits. The implicit assumption of the Normal distribution in this approach is not appropriate for skewed distributions such as Poisson, Geometric and Negative Binomial. Normal approximations perform poorly in the tail area of the these distributions. In this research, a type of attribute control chart is introduced to monitor the processes that provide count data. The economic objective of this chart is to minimize the cost of its errors which is determined by the designer. This objective is a linear function of type I and II errors. …
An Economic Alternative To The C Chart, Ryan William Black
An Economic Alternative To The C Chart, Ryan William Black
Graduate Theses and Dissertations
Because the probability of Type I error is not evenly distributed beyond upper and lower three-sigma limits the c chart is theoretically inappropriate for a monitor of Poisson distributed phenomena. Furthermore, the normal approximation to the Poisson is of little use when c is small. These practical and theoretical concerns should motivate the computation of true error rates associated with individuals control assuming the Poisson distribution. An economic alternative to the c chart is described as a statistical model of upward shift from c0 to c1 and the two charts are compared in theory. For a range of c chart …