For the data in Exercise 1, suppose the historical standard deviation had been 0.1°C instead of 0.2°C. How would that change your answers to the questions in Exercise 3?
In exercise For the data in Exercise 1, instead of the specification limits,
a) Use the historical standard deviation to set up 1, 2, and 3s limits and draw the control chart.
b) Are any points outside the 3s limits on either side?
c) Are two of three consecutive points outside of 2s on either side?
d) Are four out of five consecutive points outside of 1s on either side?
e) Are there eight points in a row on the same side of the mean?
f) Are any six points in a row increasing (or decreasing)?
g) Are any fourteen points in a row alternatively increasing and decreasing?
h) Based on your answers to parts b–g, what do you conclude?