Discuss the below:
Q. As the SPC expert in your company, you must decide on the design of an X-bar chart to be put out on a milling machine.
From past experience, you know that the process is running with mean = 10 and a standard deviation = 4. (This is the standard deviation of x, not x-bar).
Evaluate the following two candidate X-bar chart designs in terms of alpha, ARL0, beta for the shift indicated, and the resulting ARL1. Perform calculations on the blank page that follows.
What are the advantages and disadvantages of each chart? (Just a few sentences)
Fill in the charts with your result:
Chart design 1: Use 2.5 sigma control limits and subgroup size n = 5.
Alpha =
ARL0 =
Beta if mean shifts up by 1.0 sigma =
ARL1 =
Chart design 2: Use 2 sigma control limits and subgroup size n = 5.
Alpha =
ARL0 =
Beta if mean shifts up by 1.0 sigma =
ARL1 =