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Hi all -- I have to calculate a likelihood ratio test for a logit model. I found logLik, but I need to calculate the log likelihood for the model without any predictors. How can I specify this in glm? If the full model is glm(y ~ x1), is the one without predictors (y ~ 0)? Or (y ~ 1)? Is there a more direct way of getting this? -- Chris

Hi all -- I'm using trellis to generate bar charts, but there's no built-in function to generate error bars or confidence intervals, as far as I can tell. I assumed I could just write my own panel function to add them, so I searched the archive, and found a posting from the author of the package stating "... placing multiple bars side by side needs specialized calculations, which

Hi all -- I'm seeing the following commands reliably produce a crash in RGui, version 2.0.1, for both my home and office machine: > rm(list = ls(all = TRUE)); > load("dataset.R"); > library("wle"); > data.wle = wle.lm(abortion ~ year * lib.con + age + gender + + urbanism + census + income + church.att + children + educ + + religion.imp, data =

Hi all -- I'm trying to use R for my "Analysis of Categorical Data" class, but I can't figure out how to do a weighted linear trend analysis. I have a table of categorical data, to which I've assigned weights to the rows and columns. I need to calculate r and M^2, which is apparently done in SAS using "PROC FREQ" and in STATA using "correlate var1 var2

Hi all -- So I have a very simple dataset, which consists of 60 subjects, who watched one of three videos, drank one of two drinks, and completed a task. The response variable is the time to complete the task. The ANOVA command is simple enough: anova(aov(time ~ drink * video, data = df)); However, the videos were randomly selected; I need to use the random effects model for them. So

Hi all -- So I'm trying to use lattice graphics, but I want to use a sunflower plot, which doesn't seem to be part of lattice. No problem, I put together the following code, which mostly works -- *except* for the first graph it generates. If it opens the graphic device, then it draws the xygrid, clears the device, then draws the sunflowerplot. All subsequent output operations work

Hi all -- So I'm working through my statistics homework again, and trying to reproduce the examples in the book (Kirk's _Experimental Design_, third edition) in R. This is a completely randomized hierarchical design (CRH-28(A)). The B factor is completely nested within the A factor. Pages 480-482, for those playing along at home. I can use: summary(aov(value ~ a + Error(b),

Hi, I use panel.points to add points to a xyplot graphic. But I like to use the sunflowerplot to plot my points because this is very superimposed. It is possible to use this? I try but it dont work directly. It may be need to put this function inside a panel.??? Thanks Ronaldo -- Where there's a will, there's a relative. -- > Prof. Ronaldo Reis J?nior | .''`.

I know this question is very simple, but I am not figure it out I have the data frame:   test<- data.frame(year=c(2000,2000,2001,2001),x=c(54,41,90,15), y=c(29,2,92,22), z=c(26,68,46,51)) test   year    x   y   z 1 2000 54 29 26 2 2000 41  2  68 3 2001 90 92 46 4 2001 15 22 51   I want to sum the vectors x, y and z within each year (2000