Displaying 2 results from an estimated 2 matches for "dosetime".
Did you mean:
datetime
2013 Jan 06
0
How to use predict function from R2OpenBUGS results
...I made some headways on my ODE problem in R2OpenBUGS, but got stuck again. Wonder if someone could help on the following:
I am running the following code:
library(R2OpenBUGS)
dosetotal <-c(500,250)
z <-c(4,2)
grid <-c(4,15)
n.grid <-2
tol <-0.001
dim <-2
T <-2
origin <-0
dosetime <-c("1/05/2013 0:00","1/06/2013 00:00")
dose <-tail(dosetotal, n=1)
dosetime <-as.POSIXct(dosetime,format='%m/%d/%Y %H:%M')
times <-matrix(c(difftime(dosetime[2],dosetime[1],units="hours"),difftime(dosetime[3],dosetime[2],units="hours"),di...
2005 Jun 22
1
A question on time-dependent covariates in the Cox model.
...some reason there is a theory of the dose increasing its effect over
time (however it was only given (and measured) once = at the time of
examination).
I tested a model:
coxph(Surv(time,dod)~dose + dose:time)
Previously I tested the model in SAS:
proc phreg data=test;
model time*dod(0)=dose dosetime /rl ties=efron;
dosetime=time*dose;
run;
Without the interaction terms I get the same results for the two models. By
including the interaction terms I do not. The model in R gives a negative
coefficient for the interaction term which is expected to be positive (and
is so in SAS). The LRTs are...