Showing papers by "William H. Woodall published in 1985"
TL;DR: In this article, it is shown that an MCUSUM procedure is often preferable to Hotelling's TZ procedure for the case in which the quality characteristics are bivariate normal random variables.
Abstract: It is a common practice to use, simultaneously, several one-sided or two-sided CUSUM procedures of the type proposed by Page (1954). In this article, this method of control is considered to be a single multivariate CUSUM (MCUSUM) procedure. Methods are given for approximating parameters of the distribution of the minimum of the run lengths of the univariate CUSUM charts. Using a new method of comparing multivariate control charts, it is shown that an MCUSUM procedure is often preferable to Hotelling's TZ procedure for the case in which the quality characteristics are bivariate normal random variables.
394 citations
TL;DR: It is shown that a reference value larger than the value recommended by Ewan & Kemp (1960) is appropriate for the two-sided CUSUM quality control procedure when the in-control region consists of an interval of parameter values.
Abstract: A method is presented for designing quality control charts on the basis of their statistical performance over specified in-control and out-of-control regions of parameter values. This approach provides a rationale for choosing between different types of control charts. It is shown that a reference value larger than the value recommended by Ewan & Kemp (1960) is appropriate for the two-sided CUSUM quality control procedure when the in-control region consists of an interval of parameter values.
152 citations