When I fit a multivariate linear model, and the formula is defined outside the call to lm(), the method summary.mlm() fails.
This works well: > y <- matrix(rnorm(20),nrow=10) > x <- matrix(rnorm(10)) > mod1 <- lm(y~x) > summary(mod1) ... But this does not: > f <- y~x > mod2 <- lm(f) > summary(mod2) Error en object$call$formula[[2L]] <- object$terms[[2L]] <- as.name(ynames[i]) : objeto de tipo 'symbol' no es subconjunto I would say that the problem is in the following difference: > class(mod1$call$formula) [1] "call" > class(mod2$call$formula) [1] "name" As far as I understand, summary.mlm() creates a list of .lm objects from the individual columns of the matrices in the .mlm object, and then it tries to change the second element of object$call$formula, to present the name of the corresponding column as the response variable. But if the formula has been defined outside the call to lm(), that element cannot be modifed that way. A bug, perhaps? > sessionInfo() R version 2.13.0 (2011-04-13) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=Spanish_Spain.1252 LC_CTYPE=Spanish_Spain.1252 [3] LC_MONETARY=Spanish_Spain.1252 LC_NUMERIC=C [5] LC_TIME=Spanish_Spain.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base -- Helios de Rosario MartÃnez Researcher ______________________________________________ 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.
