[R] longitudinal data analysis

hie i am want to carryout a longitudinal analysis similar to the proc catmod in SAS using The Weighted least squares method.my data is in the following format. Material nbsp; time1nbsp; time2nbsp;nbsp; time3 1nbsp;nbsp; nbsp;nbsp; nbsp;nbsp; 1 1 1 1 1 2 2 2 2 2 3 3 3 .

[R] categorical data analysis

hie all i am trying to carry out a categorical data analysis but my problem is that when in i use the chi squared test some of my expected values are less than 5. is there a test that can handle this situation. the data is not a 2*2 table. its more from the social sciences where you have

[R] logrank test

hie carried out a comparison of survival curves using the log rank test in R with the values of rho ranging from -2 to 2 in increments of 0.5 the question is at rho=-1.5 the power of the test seems to fluctuate or differ from the trend shown by the other values of rho is the statistical reason

[R] cronbach's alpha

hie 1...i'm trying to carryout a relibility testusing cronbach's alpha what fuctin do i use. 2.. this is more of a statistical question.if the alpha value for all the variables is negative what does it mean. and if the alpha value is negative for all tyha variables but is

[R] specifying decimal places

hie how do I specify the number of decuimal places for my calulations thanks __ [[alternative HTML version deleted]] __ R-help@r-project.org mailing list

[R] proportional curves

hie I know this might not be the right forum but can anyone tell me what parameters i can possibly use to generate proportional survival curves using rweibull(n,shape,scale). if I plot the curves and they do not cross does it neccesarily mean that they are proprotional. thanks

[R] using survfit

hie when i use plot.survfit to plot more than one graph why I only see the last graph how do i see the other graphs.for example n=20 n1=n/2 n2=n/4 a11=4;a12=4 ;a21=4 ;a22=4 t1-array(1,c(n1)) t2-array(2,c(n1))

[R] ploting survival curves

i'm trying to plot survival curves using the following code n=20 n1=n/2 n2=n/4 a11=4;a12=4 ;a21=4 ;a22=4 t1-array(1,c(n1)) t2-array(2,c(n1)) treatgrp=matrix(c(t1,t2))

[R] r achives

sorry but how do i accsess r archives __ [[alternative HTML version deleted]] __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting

[R] programming question

hie i'm tryimg to generate two survival data using the following code (I know its ugly ) but it seems to repeat two of the variables can any one tell me whats the porblem. n=20 n1=n/2 n2=n/4 a11=1 ;a12=1.4 ;a21=16 ;a22=a12 * a21 t1-array(1,c(n1))