[R] cov.unscaled in gls object

2007-08-14 Thread Sven Garbade
Hi list, can I extract the cov.unscaled (the unscaled covariance matrix) from a gls fit (package nlme), like with summary.lm? Background: In a fixed effect meta analysis regression the standard errors of the coefficients can be computed as sqrt(diag(cov.unscaled)) where cov.unscaled is (X'WX). I

Re: [R] Interaction factor and numeric variable versus separate

2007-08-08 Thread Sven Garbade
, Sven Garbade [EMAIL PROTECTED] wrote: Dear list members, I have problems to interpret the coefficients from a lm model involving the interaction of a numeric and factor variable compared to separate lm models for each level of the factor variable. ## data: y1 - rnorm(20

[R] Interaction factor and numeric variable versus separate regressions

2007-08-07 Thread Sven Garbade
Dear list members, I have problems to interpret the coefficients from a lm model involving the interaction of a numeric and factor variable compared to separate lm models for each level of the factor variable. ## data: y1 - rnorm(20) + 6.8 y2 - rnorm(20) + (1:20*1.7 + 1) y3 - rnorm(20) +

[R] background color in strip.custom()

2006-12-04 Thread Sven Garbade
Hi all, how can I change the background color in lattice strips according to a factor level, eg: library(lattice) x - rnorm(100) y - sqrt(x) f - gl(2, 50, c(A, B)) xyplot(y ~ x | f) I like to change the background color of the strips according to the levels in f and tried several things like

[R] Fixed and random factors in aov()

2004-07-16 Thread Sven Garbade
Hi, I'm confused about how to specify random and fixed factors in an aov() term. I tried to reproduce a textbook example: One fixed factor (Game, 4 levels) and one random factor (Store, 12 levels), response is Points. The random factor Store is nested in Game. I tried str(kh.df) `data.frame':

[R] Line length in legend

2004-03-05 Thread Sven Garbade
Hi all, is it posible to alter the length of the lines in the legend() function? I think they are a little bit to short, so I changed the default value of seg.len from 2 to 6. But maybe it would be nice to have an argument, so users can change the default computed line length as they like.

[R] How to test a model with two unkown constants

2003-08-27 Thread Sven Garbade
Hi all, suppose I've got a vector y with some data (from a repeated measure design) observed given the conditions in f1 and f2. I've got a model with two unknown fix constants a and b which tries to predict y with respect to the values in f1 and f2. Here is an exsample # data y - c(runif(10,