Displaying 4 results from an estimated 4 matches for "zfit".
Did you mean:
fit
2012 Oct 08
1
Survival prediction
...quot;X * log(time)" as a fix for lack of proportionality. Is it really true that when you
use
fit <- coxph(Surv(event_time_mod, event_indicator_mod) ~ Sex +
ageC + HHcat_alt + Main_Branch + Acute_seizure + TreatmentType_binary +
ICH + IVH_dummy)
zfit <- cox.zph(fit, transform="log")
plot(zfit[8])
that the estimated function is linear? I have not yet seen such a simple time effect
and would find it interesting.
2. The code you wrote does not fit the time dependent model that you suppose; it
treats event_time_mod as...
2006 Jun 23
1
How to use mle or similar with integrate?
Hi
I have the following formula (I hope it is clear - if no, I can try to
do better the next time)
h(x, a, b) =
integral(0 to pi/2)
(
(
integral(D/sin(alpha) to Inf)
(
(
f(x, a, b)
)
dx
)
dalpha
)
and I want to do an mle with it.
I know how to use mle() and I also know about integrate(). My problem is
to give the parameter values a and b to the
2010 May 09
1
Plot polygon in 3D with rgl
Dear R-helpers, an rgl-ers in particular,
what is the easiest way to plot a section of a plane in 3D, that is
given by the xyz coordinates of the outline?
Suppose I have a polygon - which I know for sure is a set of
coordinates on the same plane. One method I found is to use surf.tri
from the geometry package, and then plot the triangles with
rgl.triangles. This method is not perfect though,
2011 Dec 26
2
Problem of COX model with time dependent covariate
Hi all,
I am trying to detect association between a covariate and a disease outcome using R. This covariate shows time-varying effect, I add a time-covariate interaction item to build Cox model as follows:
COX <- coxph(as.formula("Surv(TIME,outcome)~eGFR_BASE+eGFR_BASE:TIME"),ori.data);
coef exp(coef) e(coef) z p
eGFR_BASE