Erawin Thavorn
ABSTRACT
This paper aims to study the effect of Weibull distribution on supplier comparison via 3 examples obtained from the simulated data and real data. The study compares two supplier using lower process capability index (Cpl). To understand the effect, each example is divided into 3 cases. According to Weibull distributed process, the examples show that the result of supplier comparison is sensitive to process's shape. The symmetric process produces that the p-values of supplier comparison are not different in all cases. As a result, the comparing results are the same. On the other hand, there is a possibly misleading result in case of the right-skewed process. Although the methods of handling non-normal Cpl are applied to compare suppliers, the p-values are different and depend on skewness and kurtosis. So, the comparing results are not the same.
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Index Terms
- Effect of Weibull Distribution on Supplier Comparison using Lower Process Capability Index: The Examples Study
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