Statistics 664 – Autumn 2010
Homework 3 Solutions
In all of 5.17, 5.18, and 5.19 we are looking for patterns that we would think would be
very unlikely if the data were random.
In particular, we apply the rules discussed in
class.
Note that rules involving the twosigma or onesigma limits cannot be applied
because we don’t know if the control limits are three sigma limits and hence where the
two and onesigma limits might be.
This means that we would consider a plot to be nonrandom if
(i) One or more points are outside the control limits
(ii) We have a run of 8 or more consecutive points on one side of the center line.
(iii) We have at least 6 points in a row that are steadily increasing or decreasing.
(iv) 14 points in a row alternating up and down.
(v) An “unusual” pattern in the data/
5.17
The pattern appears random.
None of our rules are applicable.
5.18.
The pattern appears random.
None of our rules are applicable.
5.19.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '10
 BillNotz
 Statistics, Probability, Probability theory, Autumn

Click to edit the document details