Effect of sampling intervals on economic design of proposed X‐bar chart using Lorenzen‐Vance cost model

It is observed that sampling interval (h) and expected cost/hour (C) depend upon various parameters of economic design of proposed &Xmacr; chart as well as in Lorenzen-Vance (1986) cost model. The proposed &Xmacr; chart is based upon sum of chi-squares and has simplicity like Shewhart &Xmacr; chart, but more efficient than standard &Xmacr; chart. It is also as effective as CUSUM and EWMA charts for all the shifts in the process average. This paper deals with the effect of sampling intervals on economic design of proposed &Xmacr; chart, using Lorenzen-Vance (1986) cost model. This comparison shows that the performance of proposed &Xmacr; chart is very much comparable with &Xmacr; chart proposed by McWilliams (1994) for sample sizes of five, six and seven, as the expected cost per hour (C) of proposed &Xmacr; chart is very close to the expected cost per hour of McWilliams &Xmacr; chart.