similar to: X matrix deemed to be singular in counting process coxph

Dear all, I have a question regarding the use of stepAIC and polynomial (quadratic to be specific) terms in a binary logistic regression model. I read in McCullagh and Nelder, (1989, p 89) and as far as I remember from my statistics cources, higher-degree polynomial effects should not be included without the main effects. If I understand this correctly, following a stepwise model selection based

R Folk: Please forgive what I'm sure is a fairly na?ve question; I hope it's clear. A colleague and I have been doing a really simple one-off survival analysis, but this is an area with which we are not very familiar, we just happen to have gathered some data that needs this type of analysis. We've done quite a bit of reading, but answers escape us, even though the question below

Hello, I am currently trying to simulate data and analyze it using the frailty option in the coxph function. I am working with recurrent event data, using counting process notation. Occasionally, (about 1 in every 100 simulations) I get the following warning: Error in coxph(Surv(start, end, censorind) ~ binary + uniform + frailty(subject, : X matrix deemed to be singular; variable 2 My

Hi everyone, I'm a new R user (if this is a really basic question, please do excuse me...) and I'm having some questions regarding a deciles problem. I have a variable which I need to categorize according to its deciles (X). However, this categorization should be made into another variable (call it NewVar). Ex. for the quartiles case (just for the sake of exposition, since I need

Hi, there I'm currently trying to figure out how to keep my "factor" levels for a variable when moving it from one data frame or matrix to another. Example below: vec1<-(rep("10",5)) vec2<-(rep("30",5)) vec3<-(rep("80",5)) vecs<-c(vec1, vec2, vec3) resp<-rnorm(2,15) dat<-as.data.frame(cbind(resp, vecs))

Hi, I am using rpart as a part of my masters' project. I am trying to print out the resulting model using plot() function along with text() function. I am having difficulties with labels being cut-off. In text() function, I am using use.n=T option to get the number of people in each nodes but the on the lower and left part of the plot, the numbers get cut off. Thanks! Linus [[alternative

Hello, If I have two variables that are factors or characters and I want to create a new variable that is the combination of both what function can I use to accomplish this? Ex. Var1 Var2 SA100055113 19851113 And I want NewVar SA10005511319851113 Thanks in advance. Cameron Guenther, Ph.D. Associate Research Scientist FWC/FWRI, Marine Fisheries Research 100 8th Avenue S.E. St.

1. I'm attempting to test for Random Effects. I've grouped the data on subject (grid) but want to use lme to build the model without subject as a RE then add it and do anova between the 2 models. This is the result I get and it appears it's adding Random Effects. tmp.dat4 <- groupedData(Trials ~ 1 | grid, data = tmp.dat4) mod2a <- lme(Trials ~ factor(group_id) + reversal,

This is an example from chapter 11 of the 6th edition of Devore's engineering statistics text. It happens to be a balanced data set in two factors but the calculations will also work for unbalanced data. I create a factor called 'cell' from the text representation of the Variety level and the Density level using '/' as the separator character. The coefficients for the linear

--- included message ---- Thus, my question is: *What common measures exists for ranking/measuring variable importance of participating variables in a CART model? And how can this be computed using R (for example, when using the rpart package)* ---end ---- Consider the following printout from rpart summary(rpart(time ~ age + ph.ecog + pat.karno, data=lung)) Node number 1: 228 observations,

I would like to add an extension to the current name of a variable to create a new variable that is its sqrt transform. Each piece of the equation below works independently, but the left side definition fails on run. I also tried creating the variable name first, but ended up with an object that toString() did not fix. Better ideas? Example 1

Hello, i'm tring to use a cox's model for a survival analysis. I have a dataset, this is a part: VOD SESSO fonte_sct donor RT_CGY STATOBMT TEMPO morto 1 0 F mid related 1200 CP 65 1 2 0 M mid 1200 2RC 5281 0 3 0 M mid unrelated 1200

Hello list, how can I go from CALLINGout to just CALLING ? I've tried : exten => s,n,Set(newVAR=${CUT(CALLINGout,,3)}) or exten => s,n,Set(newVAR=$[CUT(CALLINGout,,3)]) But no result : [Jan 4 11:10:12] -- Executing [s at from-S:34] NoOp("SIP/s2-0000003b", "newVAR=") in new stack Asterisk 1.6.10 here. Kind regards, Jonas. -------------- next part

I need an object created in a user defined function to be accessible to another user defined function. I am fairly certain the object is correctly created as it prints when I use the return() function, however the 2nd function seems unable to use it. I am guessing objects created in functions are not globally accessible, is this correct? What is an appropriate way to pass the object to the

Hi everyone, I'm having a little trouble with working out what formula is better to use for a repeated measures two way anova. I have two factors, L (five levels) and T (two levels). L and T are both crossed factors (all participants do all combinations). So, I do: summary(aov(dat~L*T+Error(participant/(L*T)),data=dat4)) But get different results with:

Hi, May be you can try this: dat1New<-? dat1[!(duplicated(dat1$gene)|duplicated(dat1$gene,fromLast=TRUE)),] dat2<-dat1[duplicated(dat1$gene)|duplicated(dat1$gene,fromLast=TRUE),] ?lst1<-split(dat2,dat2$gene) dat3<-unsplit(lapply(lst1,function(x) {x1<- sum(apply(x[,6:32],2,function(y) y[1]>=y[2]));x2<- sum(apply(x[,6:32],2, function(y) y[1]<=y[2])); if(x1>x2) x[1,] else

I have a large 3 dimensional array of size (243,246,768) The first dimension is Rows, second is columns and the third is Time. So for each row and column, I want to calculate the mean of time steps 1:8, 2:9, 3:10 and so on and assign the values to a new array. For this I am using the following script. for(i in 1:243) { for(j in 1:246) { for(k in 1:768) { newVar[i,j,k] <- mean(

Hi all Say I have a function: myname=function(dat,x=5,y=6){ res<<-x+y-dat } for various input such as myname(dat1) myname(dat2) myname(dat3) myname(dat4) myname(dat5) how should I modify the 'res' line, to have new informative variable name correspondingly, such as dat1.res dat2.res dat3.res dat4.res dat5.res stored in the workspace. This is only an example of a complex

I'm trying to fix a problem with the GrandStream Budgetone 102. I've been reading the source code, mailing lists and other resources. Here's the scenario and the approach I have been pursuing. I'm having some problems with the AGI calls and I hope someone can give me some clarification. PSTN <---> T1,PRI * <---> Grandstream BT 102 (12)

I need to look through a dataset with two factor variables, and depending on certain criteria, create a new variable containing the data from one of those other variables. The problem is, R keeps making my new variable an integer and saving the data as a 1 or 2 (I believe the levels of the factor). I've tried using as.factor in the IF output statement, but that doesn't seem to work. Any