It's not directly extractable since it's calculated on the fly in the printing method. If you type stats:::print.summary.lm, you can see the code the leads to the calculation: It's basically (I'm leaving out some formatting stuff):
pf(x$fstatistic[1L], x$fstatistic[2L], x$fstatistic[3L], lower.tail = FALSE) where the fstatistic is calculated in summary.lm. You can write a little helper to calculate this yourself -- just something like getModelPValue <- function(m) { stopifnot(inherits(m, "lm")) s <- summary.lm(m) pf(s$fstatistic[1L], s$fstatistic[2L], s$fstatistic[3L], lower.tail = FALSE) } And you can just extract the necessary parts of summary.lm if speed is a concern. Hope this helps, Michael On Mon, Oct 24, 2011 at 1:47 PM, Jim Bouldin <bouldi...@gmail.com> wrote: > OK, what is the trick to extracting the overall p value from an lm object? > It shows up in the summary(lm(model)) output but I can't seem to extract it: > >> test2 = apply(aa, 1, function(x) summary(lm(x[,1] ~ 0 + x[,3] + x[,6]))) >> test2[[1]] > > Call: > lm(formula = x[, 1] ~ 0 + x[, 3] + x[, 6]) > > [omitted summary output] > F-statistic: 40.94 on 2 and 7 DF, p-value: 0.0001371 > > It does not seem to be obtainable from anova(lm(model)) either, only the p > values for the individual predictors. > Stumped. > > Jim Bouldin > Research Ecologist > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > ______________________________________________ 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.