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How to extract numbers from ANOVA tables?

Dear Lars,

In addition to looking at the relevant help pages, a nice thing about R is
that the objects are there for you to examine. For example:
[1] "Df"      "Sum Sq"  "Mean Sq" "F value" "Pr(>F)"
Classes 'anova' and 'data.frame':       11 obs. of  5 variables:
 $ Df     : int  1 1 1 1 1 1 1 1 1 1 ...
 $ Sum Sq : num  817.71  37.59   9.37  16.47  77.48 ...
 $ Mean Sq: num  817.71  37.59   9.37  16.47  77.48 ...
 $ F value: num  116.42   5.35   1.33   2.34  11.03 ...
 $ Pr(>F) : num  5.03e-10 3.09e-02 2.61e-01 1.41e-01 3.24e-03 ...
 - attr(*, "heading")= chr  "Analysis of Variance Table\n" "Response: mpg"

Thus, e.g., av$"Sum Sq" returns the sums of squares:
[1] 817.7129524  37.5939529   9.3709293  16.4674349  77.4757948   3.9493082
 [7]   0.1297687  14.4742372   0.9717105   0.4066688 147.4944300

You could do the same thing with the object returned by summary().

I hope that this helps,
 John

--------------------------------
John Fox, Professor
Department of Sociology
McMaster University
Hamilton, Ontario
Canada L8S 4M4
905-525-9140x23604
http://socserv.mcmaster.ca/jfox 
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