. Suppose that there are p = 2 quallty characteristics, and in correlation form both variables have variance unity and the correlation coefficient is 0.8. The In-

control value of the process mean vector is j = [0, 0], and we want to design an MEWMA control chart to provide good protection against a shift to a new mean vector of y' = [1, 1]. If an in-control ARL , of 200 is satisfactory, what value of A and what upper control limit should be used? Approximately, what is the ARL, for detecting the shift in the mean vector?