Re: [R] X matrix deemed to be singular and cbind

Thanks for your response. You are right - I am new to R and it's terminologies. I will follow up on your suggestions. On Fri, Jul 26, 2013 at 11:22 AM, Bert Gunter wrote: > Soumitro: > > Have you read "An Introduction to R." If not, do so, as some of your > confusion appears related to basic c

Re: [R] X matrix deemed to be singular and cbind

Soumitro: Have you read "An Introduction to R." If not, do so, as some of your confusion appears related to basic concepts (e.g. of factors) explained there. 1. Presumably your categorical variables are factors, not character. If so, when you cbind() them, you cbind their integer codes, yielding

[R] X matrix deemed to be singular and cbind

Hi list, While the "X matrix deemed to be singular" question has been answered in the list for quite a few times, I have a twist to it. I am using the coxph model for survival analysis on a dataset containing over 160,000 instances and 46 independent variables and I have 2 scenarios: 1. If I use

Re: [R] X matrix deemed to be singular;

Michele Santacatterina wrote: 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 midrelated 1200 CP651 2 0 M

[R] X matrix deemed to be singular;

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 midrelated 1200 CP651 2 0 M mid

[R] X matrix deemed to be singular;

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 midrelated 1200 CP651 2 0 M mid

Re: [R] X matrix deemed to be singular in counting process coxph

Dear Terry Thanks for your reply, I guess then including only the interaction term only should make sense, since a difference in group 1 between t=0 and t=1 is already taken into account in the baseline (all coefficients set to zero). My second group as I understand it should have an exp(coef_g

Re: [R] X matrix deemed to be singular in counting process coxph

What you have is a slightly more subtle variant of the following: library(survival) data(lung) mydata <- cbind(lung, newvar =2) coxph(Surv(time, status) ~ ph.karno + newvar, mydata) coef exp(coef) se(coef) z p ph.karno -0.0164 0.984 0.00585 -2.81

[R] X matrix deemed to be singular in counting process coxph

Dear all, I have a question with respect to counting process formulation of the coxph(survival) model. I have two groups of observations for which I have partitioned each observation into two distinct time intervals, namely, entry day till day 13, and day 13 till death or censorship day (of co