Optimal designs of the variable sample size and sampling intervalX¯chart when process parameters are estimated

Guaranteed conditional design of the median chart with estimated parameters

“…However, when the process parameters are unknown and are estimated from different Phase I data sets, the ARL becomes a random variable. Most researches have used the AARL to evaluate the properties of control charts with estimated parameters (see for instance in previous studies 9,12,16,23 ). But the AARL does not account for the variability in potential ARL values and, even if a particular control chart has an AARL value close to the desired in-control one, ie, ARL 0 , then the ARL values corresponding to a large number of control charts may actually be widely dispersed.…”

“…An extensive amount of researches has been done on control charts with estimated parameters. Most researchers focused on the control chart for the mean (see, for instance previous studies, [1][2][3][4][5][6][7][8][9][10][11][12] ). Moreover, control charts with estimated parameters for the variance have also been studied by researchers, such as in previous studies [13][14][15][16][17][18][19][20] Some recent developments on this topic can be found in other previous studies.…”

Proporciones de daños mecánicos y su efecto en calidad postcosecha de aguacate ‘hass’

“…So a sample of the lot will be composed of 90-150 fruits, which in many cases is not representative. In the sampling, one of the major problems is that the material is not homogeneous nor the sample is representative, since a statistical procedure to complete the required sample size is not followed (Lim et al, 2015). Therefore, choosing a suitable sample size is one of the most important aspects when evaluating fruit quality, since the probability of error in sampling is reduced (Montgomery, 2004) and will have validity and reliability, due to which the sample represents the target population and its results are extrapolated to it (Seoane et al, 2007a).…”

“…Por lo que una muestra del lote estará compuesta de 90-150 frutos, que en muchos de los casos no es representativa. En el muestreo, uno de los mayores problemas es que el material no es homogéneo ni la muestra es representativa, ya que no se sigue un procedimiento estadístico para completar el tamaño de muestra requerido (Lim et al, 2015). Por lo que, la elección de un tamaño de muestra adecuado es uno de los aspectos más importantes al evaluar la calidad del fruto, ya que se disminuye la probabilidad de error en el muestreo (Montgomery, 2004) y tendrá validez y mayor fiabilidad, debido a que la muestra representa a la población objetivo y sus resultados son extrapolables a la misma (Seoane et al, 2007a).…”

Optimal design of the side‐sensitive modified group runs (SSMGR) chart when process parameters are estimated

“…Moreover, Woodall and Montgomery pointed out that it is crucial to consider the effect of parameter estimation on a control chart. Research works investigating the impact of Case‐U on the performance of a control chart are those by Saleh et al, , Khoo et al, Wu et al, Lim et al, Du et al, and Castagliola et al, to name a few. Interested readers can see Jensen et al and Psarakis et al for an in‐depth literature review on recent Case‐U control charts.…”