Uwe Ligges wrote: > Laurent Valdes wrote: > > >>I have seen, several times, dots (like this: "y ~." ) in formula >>descriptions, noticeably in R help. >> >>I am unable to see what it does correspond to. >> >>Any ideas ? > > > All other variables (except y) from the given data.frame... > > Uwe Ligges >
Hi, Uwe, Doesn't this depend on the context? For example, z <- data.frame(y = rnorm(10), x = rnorm(10)) fit <- lm(y ~ ., z) update(fit, y ~ . + I(x^2)) The original poster did not say where he saw this formula. However, I think the reference in ?formula has the most authorative explanation. Thanks, --sundar ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
