Economic designs (with or without the addition of statistical constraints) provide reasonable approaches to the problem of choosing the parameters of a control chart. For the multivariate exponentially weighted moving average (MEWMA) control chart, the optimal choice of control limit, sample size, exponential weights for past observations and sampling interval according to economic and statistical considerations is a complex problem. This paper provides an algorithm for evaluating the ARL values for the MEWMA chart through simulation and then using these results to determine the optimal chart parameters given process cost and time information.
- Economic Control Charts
- Exponentially Weighted Moving Average Control Charts
- Multivariate Control Charts