Notes and Considerations
See the attached file "Montgomery Polynomial Regression.doc" for how-to screenshots.
Based on Example 3-1 in Montgomery (5 Ed).
In the residual diagnostics, notice the potential pattern (perhaps quadratic and cubic) in the plot of residuals vs. Cotton Weight %.
This data is also modeled using a One-Way ANOVA approach. See (example)
See also the StatSoft blog entry for Polynomial Regression.
Data Set
Link to Montgomery ANOVA data sets. (link)
Open the MS Excel file "dox7dataset.xls", go to tab "Chapter 03" and look for the data set labeled "Problem 8".
(Cotton weight percent.)
There is also a csv file available at the bottom of this same page.
Analysis or Script File
See attached file "Montgomery Polynomial Regression.R.txt".