The data in Table 9E.1 represent individual observations on molecular weight taken hourly from a chemical process. The target value of molecular weight is 1050 and the process standard deviation is thought to be about ? = 25.

(a) Set up a tabular cusum for the mean of this process. Design the cusum to quickly detect a shift of

about 1.0 ? in the process mean.

(b) Also add a headstart feature to the cusum

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