search for: hazards

My question is, how to compute hazard function(H(t)) after building the coxph model. I even aware of the terminology that differs from hazard function(H(t)) and the hazard rate(h(t)). Here onward I wish to calculate both. Here what I have done in two different methods; ##########################################################################################

Hi, I would like to compare the hazard functions of two samples using the Cox proportional hazards model. For sample 1 I have individual time-to- event data. For sample 2 I don't have individual data, but grouped data that allows to obtain a hazard function. I am wondering if there is an R function that allows to obtain a hazard ratio of the two hazard funtions (under the proportionali...

Dear all, I am trying to find a suitable R-function for parametric proportional hazard regressions. The package survival contains the coxph() function which performs a Cox regression which leaves the base hazard unspecified, i.e. it is a semi-parametric method. The package Design contains the function pphsm() which is good for parametric proportional hazard regressions when the underlying base

I am working on a target which has some structural hazards. To detect these hazards, I implemented a sub-class of PostRAHazardRecognizer. PostRAHazardRecognizer resets the hazard state on a basic block basis. So, how to detect hazards that may occur between the end of a basic block and the beginning of another basic block ? Thanks ! --------------...

Dear Forum, I have a question about interaction estimate in the Cox model: why the hazard ratio of the interaction is not produced in the summary of the model? (Instead, the estimate of the coefficient is given in the print of the model.) # Example: modINT <-cph( Surv(T_BASE, T_FIN,STATUS)~ NYHA + ASINI + RFP + FE_REC + XX_PR*XX_DISF) print(modINT) coef se(coef) z

Dear list, is there a function available which provides an estimate of the hazard function based on a cox proportional hazard model? I only found the cumulative hazard and the survival function as survfit options. Thanks for your help Peter

hi, LLVM, I found there is a flag DisableHazardRecognizer in TargetInstrImpl.cpp. I still don't understand how llvm detects data hazard in pre-RA-sched. pre-RA-sched is based on SDNode and all operands are vregs. Even you can calculate the operators of SDNodes, the data hazard in vreg are not same as physical register data hazard. Is it useful to optimize processor pipeline? thanks, --lx

...cumulative baseline hazard function , H_o(t_i), should be linear across time. Once I have, H_o(t_i), to get at h_o(t_i) I then need to reverse the cumsum operation. The corresponding plot should have a constant baseline hazard over time. I am aware of cox.zph() for testing the proportionality of hazards assumption. Thanks Alex Alex Hanke Department of Fisheries and Oceans St. Andrews Biological Station 531 Brandy Cove Road St. Andrews, NB Canada E5B 2L9 [[alternative HTML version deleted]]

...the data hazard in vreg are not same as physical register data hazard. Is it useful to optimize processor pipeline? The hazard recognizer enforces the instruction itineraries that are defined for some subtargets. The itineraries specify resource usage at each pipeline stage and latency. The "hazards" being recognized are resource conflicts, like two independent instructions using the FP unit, or read after write latency. It does not deal with WAR physical register hazards. (Targets are migrating to a more flexible and efficient machine model now that does not use the hazard recognizer.)...

http://r.789695.n4.nabble.com/file/n3058505/file.csv file.csv Hi, Rusers I have a problem in making a rcspline.plot with a Hmisc package. My data is in the upload attachment. My programme as follows: library(Hmisc) A<-read.csv("file.csv",header=TRUE) attach(A)

Dear R-users, I would like to show you a simple example that gives an overview of one of my current issue. Although my working setting implies a different parametric model (which cannot be framed in the glm), I guess that what I'll get from the following example it would help for the next steps. Anyway here it is. Firstly I simulated from a series of exposures, a series of deaths (given a

Hi, I'm student from canada, and i'work in survival analysis.I want to know if there is a hazard function or cumulative hazard function in R or not, i know how to program it, but it is easy to use it if they exists in R. Thanks. Yassir

Dear R-users, I would like to fit a fully parametric proportional hazard model with a weibull baseline hazard and a logit link function. This is, the hazard function is: lambda_i (t) = lambda_0 (t) psi (x_i* beta) where lambda_0 is a weibull distribution and psi a logistic distribution. Does someone know a package and/or function on R to do this? Thanks. -- M.L. Avendaño [[alternative HTML

Dear all, Is there a way to calculate the non-cumulative hazard (instantaneous hazard), which is the product of baseline hazard and exp{beta*covariate} ? I knew in survfit, we can get the estimator of cumulative baseline hazard, but how can we get the non-cumulative one? Thank you very much! Koshihaku -- View this message in context:

Dear R-users, I am checking the proportional hazard assumption of a cox model for a given covariate, let say Z1, after adjusting for other relavent covariates in the model. To this end, I fitted cox model stratified on the discrete values of Z1 and try to get beslow estimator for the baseline cumulative hazard function (H(t)) in each stratum. As far as i know, if the proportionality assumption

Hi, I'm new to R and using it for Cox survival analysis. Thanks to this great forum I learned how to compute the HR with its confidence interval. My question would be: Is there any way to get the p-value for a hazard ratio in addition to the confidence interval? Thanks, Thierry -- Thierry Panje Visiting Student Researcher Department of Psychology Stanford

...planning to add a second pass to verify these special cases but wanted to make sure there is not a simpler and consistent way before proceeding. And you're right, another way is also to make sure that the final or the first instruction of a basic block are not instructions prone to structural hazards (this should not happen so often...). Btw, you didn't reply on the mailing list... is it just an omission ? Getting it on the mailing list might be helpful for the llvm community ;) Best regards, Damien On Fri, Feb 11, 2011 at 1:30 AM, Arnaud Allard de Grandmaison <Arnaud.AllardDeGra...

...> not understand why > a) the coefficients in the survreg model are the opposite (negative when the > other is positive) of what I have in the cox model? are these not the log(HR) > given the categories of these variable? No. survreg() fits accelerated failure models, not proportional hazards models. The coefficients are logarithms of ratios of survival times, so a positive coefficient means longer survival. > b) how come the intercept coefficient changes (the scale parameter does not > change)? Because you have reversed the order of the factor levels. The coefficient of tha...

Hello: So i've fit a hazard function to a set of data using kmfit<-survfit(Surv(int, event)~factor(cohort)) this factor variable, "cohort" has four levels so naturally the strata variable has 4 values. I can use this data to estimate the hazard rate haz<-n.event/n.risk and calculate the cumulative hazard function by H<--log(haz) Now, I would like to plot this

Hello , I am hoping for some advice regarding obtaining the values for the hazard function in a cox regression that I have undertaken. I have a model in the following form, analysed with the package survival (v. 2.34-1) and a log-log plot obtained using Design (v. 2.1-2). For two variables, the lines in the survival curves crossed. The statistician I been obtaining advice from (who does not