Linked Questions
11 questions linked to/from Extended Cox model and cox.zph
9
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1
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24k
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Interpreting R coxph() cox.zph()
The results of my coxph() are significant, yet the cox.zph() test is significant too.
From my understanding of it, the ...
- 135
3
votes
2
answers
3k
views
Violated non-proportional hazards - Cox regression model of time-dependent covariable
I have been reading a lot on Cross Validated for a while now, but this is my first post here. Thanks for all the help I've received!
I am currently working on a project where we are trying to estimate ...
- 63
2
votes
1
answer
3k
views
Is the proportional hazards assumption violated (interpreting Schoenfeld residuals)? What is my best option if so?
I am using an extension of the Cox model in the counting process format (Andersen-Gill model), with time-dependent covariates. The analysis is investigating the effect of an intervention on hospital ...
- 73
2
votes
1
answer
922
views
Hazard Rate Modelling in R
I am writing my thesis about bankruptcy prediction Pr(Y=1) through a sentiment score I have calculated (x1) and a control variable called Z-Score (x2). However I am very unsure about how to integrate ...
- 41
3
votes
2
answers
186
views
Should I use Cox model?
In a study of crowdfunding, I am investigating the relationship between the reputation of a person seeking funding for a project (a continuous variable) and the proportion of funding target received (...
- 715
2
votes
1
answer
393
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Computing Chi-square values from Schoenfeld residuals
Based on page 164-165 of [Collett:Modelling Survival data in medical research (Third edition-2014)] the Schoenfeld for individual test and for global test can be obtained as follows[1].
However, ...
- 137
2
votes
1
answer
816
views
Should the proportional hazards assumption be met for cox model with time dependent covariates? What about recurrent event models?
This question has been asked here before but in each thread I found, there was some disagreement about whether the proportional hazards (PH) assumption needs to be met for cox models with time ...
- 47
2
votes
1
answer
734
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Stratified-Extended Cox regression modeling to deal with survival data with time-varying covariates
I'm working on Cox regression in my PhD research and I would like to know some references about applying the stratified-extended cox regression model on a real life data.
I'm interested about ...
0
votes
1
answer
317
views
Cox survival PH violated variable is part of an interaction
One of my main predictors violates the PH assumption. I've been reading different ways to deal with this for a while and have decided on an interaction with time after making a person-period file (...
- 11
1
vote
1
answer
104
views
Survival analysis proportional hazards violation
I've been using Cox for survival analysis with the goal of identifying the effect of 5 different levels of a treatment on survival. My dataset is not small and has 130 covariates after dummy encoding.
...
- 409
1
vote
1
answer
80
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Should the curve be around zero when assessing the smoothed scaled Schoenfeld residual plot for proportional hazard assumption?
I'm using the smoothed scaled Schoenfeld residual plot to assess the proportional hazard assumption. I have a decent understanding of what a smoothed scaled Schoenfeld residual plot shows, but I'm ...
- 333