Displaying 4 results from an estimated 4 matches for "intageatmhcindex".
2008 Dec 28
1
cox regression warning/error messages
...or each dummy variable, or is it
correct simply to run the analysis on the original variable?
The code employed to generate the analysis follows:
Any assistance is appreciated,
Bob
cox.NV <- coxph(Surv(recidivism$intDaysUntilFNVPO,
recidivism$Event_nv) ~ recidivism$strGender +
recidivism$intAgeAtMHCIndex + recidivism$PRE.nv + group +
recidivism$MHC.nv + recidivism$SNFP , data = recidivism)
> summary(cox.NV)
Call:
coxph(formula = Surv(recidivism$intDaysUntilFNVPO, recidivism$Event_nv) ~
recidivism$strGender + recidivism$intAgeAtMHCIndex + recidivism$PRE.nv +
group + recidivism$MH...
2009 Mar 14
1
obtaining the values for the hazard function in a cox regression
...uch values, to
better understand what is occurring in the log plots.
Below is the code that I have been using. Any assistance is appreciated,
regards
Bob
library(survival)
recidivismv <- read.csv("g://Chapsurv_v.csv",header=T)
cox.V <- coxph(Surv(intDaysUntilFVPO, Event_v) ~ intAgeAtMHCIndex +
PRE + group + MHC + strGender, data = recidivismv)
summary (cox.V)
# produces a log-log plot
mvfit <- survfit (Surv(recidivismv$intDaysUntilFVPO,
recidivismv$Event_v) ~ MHC, data = recidivismv)
neg.ll <- function(mvfit) -log(-log(mvfit))
library (Design)
survplot(mvfit, fun = neg.ll, c...
2009 Mar 16
0
hazard function in a Cox model
...values. I am wanting to confirm
whether basehaz is the correct command to obtain such values, to
better understand what is occurring in the log plots.
--- end inclusion ----
The best tool for understanding what is happening is cox.zph.
cox.V <- coxph(Surv(intDaysUntilFVPO, Event_v) ~ intAgeAtMHCIndex +
PRE + group + MHC + strGender, data = recidivismv)
zpfit <- cox.zph(cox.V, transform='identity')
plot( zpfitp[1]) #plot for the first variable
plot( zpfitp[2]) #plot for the second
You will get a plot of beta(t) versus time, a horizontal line correspond...
2009 Mar 28
1
stratified variables in a cox regression
...R examples I have seen.
Below is my current code - is there a method to test whether the
stratified variables should be included in the final model at all?
library(survival)
recidivismv <- read.csv("g://Chapsurv_v.csv",header=T)
cox.V2 <- coxph(Surv(intDaysUntilFVPO, Event_v) ~ intAgeAtMHCIndex +
PRE + group + strata (MHC, strGender), data = recidivismv)
regards
Bob