Suppose that there are p = 4 quality characteristics, and in correlation form all four variables have variance unity and that all pairwise correlation coefficients are 0.9. The in-control value of the process mean vector u’ = [0, 0, 0, 0], and we want to design a MEWMA control chart to provide good protection against a shift to anew mean vector of y’ = [1, 1, 1, 1]. Suppose that an in-control ARL0 of 500 is desired. What value of  and what upper control limit would you recommend? Approximately, what is the ARL1 for detecting the shift in the mean vector?