STAT 3504
Assignment #3
Approx
100 marks
DUE:
Monday, February 22
Use SAS to help you do the following questions.
Hand in a copy of BOTH code and output.
Remember to put a FOOTNOTE statement with you name and student number at the beginning of your
program.
1.
#3 on Assignment 2 Continued
For problem #18.17 in your text the data is in the data disk that comes with your text under the file
name
ch18pr17.dat
It is also in
stat3504a\ch18pr17.dat
column 1 = response,
column 2 = factor level (winding speeds),
column 3 = observation number
In an experiment to study the effect of the speed of winding thread (1: slow, 2: normal, 3:fast,
4:maximum) onto 75yard spools,
16
runs of 10,000 spools each were made at each of the
4
winding speeds.
The response variable is the number of thread breaks during the production run.
The
results (in time order) are as given in the data set.
a)
Prepare residual sequence plots (see code on Lab 3 handout).
What are your conclusions?
b)
For each winding speed, examine the three relations given in class involving the factor level
means, variances & standard deviations (also given in the table on p791 of your text), and
determine the transformation that would be most appropriate.
Explain
why you chose this
transformation.
Do by hand and show your work
using the values printed out for #3(c) of
assignment
2
.
Using the transformation
(Y)
=
Y
ln
′
c)
Obtain sidebyside box plots for the factor levels.
Do these show any obvious outliers?
d)
For each factor level, have the fitted value and the standard deviation printed out.
Are the
standard deviations fairly similar for all winding speeds?
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 Spring '10
 Ann
 Normal Distribution, factor level, factor levels, data set.

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