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One-Way ANOVA Example 1 (Statistica)

Notes and Considerations

One-Way ANOVA.

Based on Example 3-1 in Montgomery (5 Ed).
See the attached file "Montgomery One-Way ANOVA.doc" for how-to screenshots.
In the residual diagnostics, notice the potential pattern (perhaps quadratic) in the plot of residuals vs. Cotton Weight %.
Using an ANOVA method, the different Cotton Weights are treated as categorical levels, not continuous measurements. 
To model a higher order term (e.g. x2), it is helpful to use a regression model approach.  See (example

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".
Alternatively, load the file "cotton_wt_pct.csv".  (It is the same data.)

Analysis or Script File

See attached file "Montgomery One-Way ANOVA.stw".