Thank you David, but how to get the value of 0.015939 present in s.npk.aov, and not given by s.npk.aov$coef["block","Pr(>F)"] ?
On the other, the procedure to extract coefficients from a summary of lm or aov should be the same. Andrea On 21 Apr, 2010, at 3:20 PM, David Winsemius wrote: > > On Apr 21, 2010, at 8:37 AM, Andrea Bernasconi DG wrote: > >> Dear Madame, Dear Sir, >> >> I am able to obtain the coefficients from a 'summary' of 'lm', but NOT from >> a 'summary' of 'aov'. >> The following example shows my steps. >> >> ## Initialize >> rm(list = ls()) # remove (almost) everything in the working environment > > @#$%^&*() DON'T DO THAT.... luckily I left off the "l" when I copied and > pasted but otherwise this would have trashed my workspace. > >> utils::data(npk, package="MASS") # get data >> model <- yield ~ block + N*P*K >> >> ## Using lm >> npk.lm <- lm(model, npk) >> ( s.npk.lm <- summary(npk.lm) ) >> >> ... >> Estimate Std. Error t value Pr(>|t|) >> (Intercept) 54.8750 0.8021 68.415 < 2e-16 *** >> block1 1.7125 1.3893 1.233 0.24131 >> block2 1.6792 0.8021 2.093 0.05822 . >> block3 -1.8229 0.5672 -3.214 0.00744 ** >> ... >> >> s.npk.lm$coef["block1","Pr(>|t|)"] # this works >> [1] 0.2413061 >> >> ## Using aov >> npk.aov <- aov(model, npk) > > str(npk.aov) > > > npk.aov$coefficients > (Intercept) block2 block3 block4 block5 block6 > N1 > 51.8250000 3.4250000 6.7500000 -3.9000000 -3.5000000 2.3250000 > 9.8500000 > P1 K1 N1:P1 N1:K1 P1:K1 N1:P1:K1 > 0.4166667 -1.9166667 -3.7666667 -4.7000000 0.5666667 NA > > Or reading the help pages one might have tried, although I will admit that > the differences in parametrization confounded my efforts at describing a > linear combination of those results to create the simpler result offered > above: > > ?model.tables > > model.tables(npk.aov, "effects") > Tables of effects > > block > block > 1 2 3 4 5 6 > -0.850 2.575 5.900 -4.750 -4.350 1.475 > > N > N > 0 1 > -2.8083 2.8083 > > P > P > 0 1 > 0.5917 -0.5917 > > K > K > 0 1 > 1.9917 -1.9917 > > N:P > P > N 0 1 > 0 -0.9417 0.9417 > 1 0.9417 -0.9417 > > N:K > K > N 0 1 > 0 -1.175 1.175 > 1 1.175 -1.175 > > P:K > K > P 0 1 > 0 0.14167 -0.14167 > 1 -0.14167 0.14167 > > > >> ( s.npk.aov <- summary(npk.aov) ) >> >> ... >> Df Sum Sq Mean Sq F value Pr(>F) >> block 5 343.29 68.659 4.4467 0.015939 * >> N 1 189.28 189.282 12.2587 0.004372 ** >> P 1 8.40 8.402 0.5441 0.474904 >> ... >> >> s.npk.aov$coef["block","Pr(>F)"] # this does NOT works >> >> ... >> NULL >> ... >> >> How to obtain the coefficients from a 'summary' of 'aov' ? >> >> In advance, I thank you very much for your eventual answer. >> >> Sincerely, Andrea Bernasconi >> >> mobile: +41 79 621 74 07 >> URL: >> http://web.me.com/andrea.bernasconi.dg/Andrea_Bernasconi_DG_home_page/HOME.html >> >> ______________________________________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. > > David Winsemius, MD > West Hartford, CT > mobile: +41 79 621 74 07 ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.