anova and intercept
My usual advice on getting nonstandard F tests out of anova() is to fit the models explicitly and compare. So how about this? fit1 <- lm(diff(extra,10) ~ 1, sleep) fit0 <- update(fit1, ~ -1) anova(fit0, fit1) -pd
On 26 Dec 2022, at 13:49 , Gabor Grothendieck <ggrothendieck at gmail.com> wrote: Suppose we want to perform a paired test using the sleep data frame with anova in R. Then this works and gives the same p value as t.test(extra ~ group, sleep, paired = TRUE, var.equal = TRUE) ones <- rep(1, 10) anova(lm(diff(extra, 10) ~ ones + 0, sleep) This gives output but does not give an F test at all. ones <- rep(1, 10) anova(lm(diff(extra, 10) ~ 1, sleep) Maybe there should be some way to force an F test to be produced for the intercept in anova for consistency with t.test so that the second code can be used. -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com
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