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sorry but how do i accsess r archives __________________________________________________ [[alternative HTML version deleted]]

how do l programme the logrank test. l am trying to compare 2 survival curves --------------------------------- [[alternative HTML version deleted]]

I am trying to generate survival data using R .Im trying to randomly generate a column of 1s and 0 and another column randomly generated using an exponential distribution but l cant seem to get the random function. how do l go about it thanks in advance rt chiruka --------------------------------- [[alternative HTML version deleted]]

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 greater than 0.7 for some sections of the variables what does that mean thanks in advance

...at.math.ethz.ch > > When replying, please edit your Subject line so it > is more specific > than "Re: Contents of R-help digest..." > > > Today's Topics: > > 1. Re: use mathematics formula (hadley wickham) > 2. creating different strata (raymond chiruka) > 3. converting a data frame to ts objects (fatih > ozgul) > 4. Running R function as a Batch process (d. > sarthi maheshwari) > 5. Re: creating different strata (raymond > chiruka) > 6. Re: Filled step-function? (Beate Kowalczyk) > 7. Re: creating different...

i would like to add a variable to an existing matrix by manipulating 2 previous variables eg for the data m treat strata censti survTime [1,] 1 2 284.684074 690.4961005 [2,] 1 1 172.764515 32.3990335 [3,] 1 1 2393.195400 24.6145279 [4,] 2 1 30.364771 8.0272267 [5,] 1 1 523.182282 554.7659501 l

l want to create a column of 1 and 2 randomly what command should l use eg treatment strata 1 1 2 0 1 1 2 1 2 0 2 1 2 0 1 0 these should be created randomly secondly if l have

l'm trying to find the "survdiff" package/function but it seems i cant get it how do l instal it if its not there thanks --------------------------------- [[alternative HTML version deleted]]

hie how do you compute the logrank test using R what commands do you use my data looks something like just an example treatmentgrp strata censoringTime survivalTime censoring act.surv.time [1,] 2 2 42.89005 1847.3358 1 42.89005 [2,] 1 1 74.40379 440.3467 1 74.40379 [3,] 2 2

hie how do I specify the number of decuimal places for my calulations thanks __________________________________________________ [[alternative HTML version deleted]]

hie l would like to create about ten strata l have tried using sample(c(1,2),1,replace=TRUE) but all l get is a vector of 1 and 2 if i change it to sample(c(1,10),1,replace=TRUE) it gives me a vector of 1 and 10 how do l go about it --------------------------------- [[alternative HTML version deleted]]

hie l would like to create a 6th column "actual surv time" from the following data the condition being if censoringTime>survivaltime then actual survtime =survival time else actual survtime =censoring time the code l used to create the data is s=2 while(s!=0){ n=20 m<-matrix(nrow=n,ncol=4)

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)) treatgrp=matrix(c(t1,t2))

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 from strongly agree to strongly disagree. i know i can collapse vthe tables but there is a loss of

...gt; 1. Re: impossible to open SPSS file (Frank Thomas) > 2. Problem with the installation of "install R" on Sun Solaris > (Vipin Singhal) > 3. Re: Concepts question: environment, frame, search path > (Duncan Murdoch) > 4. adding column to a matrix (raymond chiruka) > 5. Re: intersect filled.contour and polygon (Roger Bivand) > 6. Re: to draw a smooth arc (Jim Lemon) > 7. Odp: adding column to a matrix (Petr PIKAL) > 8. Re: Problem with the installation of "install R" on Sun > Solaris (Prof Brian Ripley) > 9. Re: Pr...

in R when carring out the log rank test is the censored variable denoted by 1 or 0 or its of no consequence. thanks --------------------------------- always stay connected to friends. [[alternative HTML version deleted]]

hie is it possible to get the code for the logrank test l just need the chisquared value. thanks --------------------------------- [[alternative HTML version deleted]]

l would like to create the following matrice treatmentgrp strata 1 1 1 1 1 1 1 2 1 2 1 2 2 1 2 1 2 1 2 2 2 2 2 2 l should be able to choose the size of the treatment grps and stratas the method l used intially creates the

Hie I am trying to install Package DAAG this is the error I get > library(DAAG) Loading required package: randomForest Error: package 'randomForest' could not be loaded In addition: Warning message: In library(pkg, character.only = TRUE, logical.return = TRUE, lib.loc = lib.loc) : there is no package called 'randomForest' what should i do thanks The University of Fort Hare

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)) t2<-array(2,c(n1)) treatgrp=matrix(c(t1,t2))