# hazard

1. ### cox model with time dependent covariate

I am trying to fit a cox model: h(t, beta) = h0(t)exp(X*beta), while X = (x1, x2, ..., xN) but, for instance, x1 is binary with value of 0 or 1, but the hazard ratio of 1 and 0 is not proportional: t: 1 2 3 4 5 6 7 .... hazard ratio: 0.2 0.3...
2. ### kaplan-meier from a survival function

hi, let assume I have a survival function, given as a solution from a continuous model. To be precise, the cumulative hazard is calculated, Ch(t), and then S(t) = exp(-Ch(t)). How would you simulate a Kaplan-Meier plot based on this? Here, the so called clinical trial simulation is performed...
3. ### What if events also have factors, not only the studied subjects!!

Hello everyone... despite my a little knowledge in survival analysis and its available models.... I have the following question: What I know that Cox models offer a hazard function, with the assumption of proportionality of the hazard for different studied subjects. The frailty component...
4. ### Confidence intervals for survival estimates with combinations of risk factors

Dear all, I have time-to-event data for patients with epilepsy. We have produced a parsimonious multivariable model for this event and therefore can obtain the probability of the event at each recorded time point. In addition to this, we can work out the survival estimate at a time point...