This bug is not quite fixed - the example from my original report now = works using R-2.2.1, but
plot(Uniform, 6) does not. The bug is due to if (show[6]) { ymx <- max(cook, na.rm =3D TRUE) * 1.025 g <- hatval/(1 - hatval) # Potential division by zero here # plot(g, cook, xlim =3D c(0, max(g)), ylim =3D c(0, ymx),=20 main =3D main, xlab =3D "Leverage", ylab =3D "Cook's distance",= =20 xaxt =3D "n", type =3D "n", ...) ... All other values of 'which' seem to work fine. Sorry not to have checked = this in the beta version, Heather >>> Prof Brian Ripley <[EMAIL PROTECTED]> 12/06/05 04:10pm >>> Curiously, I was just looking at that, since I believe the answer = should=20 be NaN, and some optimizing compilers/fast BLASes are not giving that. (There's an example in reg-test-3.R.) So I think we need to return NaN=20 when hat is within rounding error of 1. My take is that plot.lm should handle this: you will see most but not = all=20 cases have na.rm=3DTRUE in calculating ylim, but as Inf is theoretically impossible it has not been considered. Note that plot.lm does not use rstandard and so needs a separate fix. Thanks for the report On Tue, 6 Dec 2005 [EMAIL PROTECTED] wrote: > Full_Name: Heather Turner > Version: 2.2.0 > OS: Windows XP > Submission from: (NULL) (137.205.240.44) > > > Standardized residuals as calculated by rstandard.lm, rstandard.glm and = plot.lm > are Inf/NaN rather than zero when the un-standardized residuals are = zero. This > causes plot.lm to break when calculating 'ylim' for any of the plots of > standardized residuals. Example: > > "occupationalStatus" <- > structure(as.integer(c(50, 16, 12, 11, 2, 12, 0, 0, 19, 40, 35, > 20, 8, 28, 6, 3, 26, 34, 65, 58, 12, 102, 19, = 14, 8, > 18, 66, 110, 23, 162, 40, 32, 7, 11, 35, 40, = 25, 90, > 21, 15, 11, 20, 88, 183, 46, 554, 158, 126, 6, = 8, > 23, > 64, 28, 230, 143, 91, 2, 3, 21, 32, 12, 177, = 71, > 106) > ), .Dim =3D as.integer(c(8, 8)), .Dimnames =3D > structure(list(origin =3D c("1", "2", "3", "4", "5", "6", = "7", > "8"), > destination =3D c("1", "2", "3", "4", "5", = "6", "7", > "8")), .Names =3D c("origin", "destination"))= , > class =3D "table") > Diag <- as.factor(diag(1:8)) > Rscore <- scale(as.numeric(row(occupationalStatus)), scale =3D FALSE) > Cscore <- scale(as.numeric(col(occupationalStatus)), scale =3D FALSE) > Uniform <- glm(Freq ~ origin + destination + Diag + > Rscore:Cscore, family =3D poisson, data =3D occupationalSta= tus) > residuals(Uniform)[as.logical(diag(8))] #zero/near-zero > rstandard(Uniform)[as.logical(diag(8))] #mostly Inf/NaN > plot(Uniform) #breaks on qqnorm plot (or any 'which' > 1) > > This could be fixed by replacing standardized residuals with zero where = the hat > value is one, e.g. > rstandard.glm <- function (model, > infl =3D lm.influence(model, do.coef =3D = FALSE), > ...) { > res <- infl$wt.res > hat <- infl$hat > ifelse(hat =3D=3D 1, 0, res/sqrt(summary(model)$dispersion * (1 - > infl$hat))) > } > etc. > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel=20 > > --=20 Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/=20 University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel