[Cox proportional hazards regression][1] is a very popular, semi-parametric method for survival analysis.

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Hazard Ratio Curve

Can someone please tell me, which SAS procedure to use or any other method in SAS to draw a Hazard Ratio Curve as in the image below. Thank you.
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Are there any possibilities to check model assumptions or any diagnostic for the proportional hazards model with correlated times?

As far as I know, regular proportional hazards model have assumptions that times have to be independent, hazards for each variables should be proportional and there should be noninformative censoring. ...
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Can proportional hazard regression predict the S(t) of subjects?

In my understanding, cox PH model can only give estimates of coeffs of regressors and then interpretations can be drawn. Since it does not assume a base hazard function, it cannot give an estimated ...
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Some doubts about survival analysis

I'm struggling to perform a correct and unbiased survival analysis, but I have some doubts. Data I observe a population of posts on a blog within a temporal window $[T_{0}, T_{final}]$. Each post ...
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Modelling proportional hazards in Cox Model using coxph in R

Assume I have a heterogeneous sample with two categorical variables A and B, each with 2 levels. Now I want to measure the effect of these on the survival function. So we assume proportional hazard, ...
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PH assumption: categorical variable (1 category does not interact with time)

After checking the PH assumption in STATA I found one variable (4 categories, 1=ref.) to interact with time (using 'tvc'). The 3th and 4th category had p-values <0.05. However, the 2nd category did ...
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how can I save the survival probability that used to calculate NRI for an indiviual?

I am trying to save the survival probability that used to calculate NRI (i.e. in the survIDINRI package) for an individual. and I wanted to use these probabilities to further analyse what kind of ...
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Cox model on bank customers

I am setting up a Cox model, to model the probability that new customers leave the bank . I had a nice set up, with plenty of significant explanatory variables, until the result of one categorical ...
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coxph R Squared Interpretation in R [duplicate]

A classmate and I have been looking over some stats regarding a study looking at the (lets call it) survival rate of an item of food. He ran his analysis using coxph to generate a model to compare the ...
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Cox/ Binomial Regression: How to reconcile Non-significant model with significant IVs

I'm been performing some survival and regression analyses corresponding to an event of interest being death or a certain surgical procedure, namely a shunt revision for pediatric neuro-surgical ...
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Setting up dataset for Cox regression with time-dependent variables

I posed a question about how to set up the code for this question here (SAS/proc phreg code) and @Fomite suggested that I pose a separate question about whether my data are set up correctly. ...
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SAS/proc phreg code

Background: I'm studying people seeking help. Participants described contacts with between 1 and 3 "responders" (e.g., friends, the police) in order- for example, a participant could have contacted ...
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Interpreting Cox & Binomial Regression: non-significant Chi-Square values w/ significant wald statistics

Scenario A: In Cox regression, the chi square analysis of the -2 log likelihood (or the omnibus in binomial) is not significant, but some of the values of the Wald statistic corresponding to some of ...
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How to interpret the overall model output of a Cox model?

I am running Cox regression analysis. I have read FOX's manual and I understand how to interpret the output of each predictor. But I am not sure how I should be interpreting the overall model output, ...
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Extended Cox model and cox.zph

I have previously had experience only with Cox PH model and its assumptions checking. Now for the first time I have my clients data with most of the covariates varying in time, only a few are fixed ...
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Survival Analysis Cox Ph Predict values

I'm coming with a question that I think is easy for most of you. But as I'm a newbie in Survival Analysis (I started 2 days ago), I can't figure out how to do it. I'm given a data set on ...
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ANOVA or AOV in R (cox ph)

I was wondering if you might be able to help me, I am doing a cox ph on some data – which looks at the effect of a poor diet (8x sugar) and the genotype (3 in total – 2 control, 1 experimental) on the ...
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Validate predictive power of Cox proportional hazards for individual observations

Note I've edited the example to be more intuitive and closer to my real data Intro I've got data on customers purchases and with it am trying to predict which customers are more likely to make next ...
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Difference between Cox Proportional Harzards Model and interval-based logistic model for survival regressions

I have a dataset of timestamped trader transactions (to the second). I want to conduct a survival analysis on the trades where a trade is started at startTime and ...
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Cox MSM or Recurring Event?

I have dataset containing clients' history of active and inactive periods (if there is any) up to present day. Also lots of info as time dependent covariates. I want to model this as MSM, where both ...
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Imposing follow-up time cutoffs on censored data for cox regression

When fitting cox regression models, is it valid to impose a cutoff for censored samples to have been followed for at least a given stretch of time for inclusion in the analysis?
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What model fit / predictive accuracy measure can be used to cross validate a Cox PH model with censored data?

How would you go about validating a Cox PH model with censored data? I am trying to run a Cox PH model on a dataset with observations that failed, and observations that are censored. Normally, I use ...
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Best packages for Cox models with time varying covariates

I am working on a project using Cox models with time varying covariates. My questions are: What are some good examples of conducting this analysis? What is the best R package to conduct this ...
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How can I make an ANCOVA in R (Prior to a Cox ph model)?

I want to make an ANCOVA analysis of the survival rate of flies after being on a bad diet for the first 21 days of their lives compared to those always on a normal diet. I have studied the responses ...
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Modelling credit risk by Ornstein Uhlenbeck process incorporating macro economic variable

I have a data set on default, application score and some macroeconomic variable, I want to model the next default as poison process whose parameter is itself random, it comes from an ornstein ...
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How to calculate adjusted HR?

What is the difference between crude HR and adjusted HR in Cox regression? How do we calculate adjusted HR?
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Can Cox models be used with time-varying covariates?

I work at a hard drive manufacturer. In my project, we have huge sets of testing data of hard drives. Most of them are time-varying covariates. My colleges are using cox regression. I doubt it. ...
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Cox regression with two dependent expanatory variables

I am doing a Cox regression to model how survival times of sick patients, after taking a certain number of pills. There are in total 10 different pills patients can ...
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scaled Schoenfeld residuals slope of regression line

If a regression line of scaled Schoenfeld residuals versus time (or log time) has a non-zero slope, proportionality is violated. However, what can we tell from the slope of the regression line? If it ...
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Schoenfeld residual independent of time?

I've seen it claimed (e.g. in these notes ) that "Schoenfeld residuals are, in principle, independent of time." Can this be right? Consider the following situation: You are using a Cox model to ...
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Age-matching for 2 samples in Cox Regression

I have 2 samples with a very significant mean age difference: Sample0: less-invasive,lower-risk surgery. mean age = 70. n=159 , deaths = 24 Sample1: higher-risk surgery. mean age = 60. n=86, deaths ...
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using caret and glmnet for variable selection

Im using the caret and glmnet package for variable selection. I only want to find the best model and the coefficients and use ...
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Interpretation of coefficients of glmnet - LASSO/Cox model?

I have done a LASSO / Cox model run for a large dataset of 10K observations which has 1200 Variables. ...
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Comparing different methods of discrete-time survival analysis

I'm investigating a discrete time survival problem (the units are months and exit times range from month 1 to 36). From looking around so far, it seems like there are a few different types of model ...
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Which model to use for survival analysis when there are different times of entry into the sample?

I have a data set containing the trades executed by many traders as follows: ...
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Cox model with different follow-up times in groups

We have a dataset where the non-exposed group has follow up to 5 years but the exposed group has follow up only to 1 year (>1 year not possible in the dataset). Analysis is with Cox regression. ...
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Differences between logistic regression parameter estimates and Cox-proportional hazard parameters

We have been working on a survival analysis. We are examining tree seedling survival over a decade with annual to biannual census intervals. We have been using the package coxme in R for a mixed ...
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R Packages for rank-preserving structural failure time model (RPSTM)

I have a randomized clinical trial data that has high percentage(30-40% in both arms) switching over to a different treatment regimen. By browsing through some literature, I am inclined to perform ...
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Heterogeneity test for risk factor association (hazard ratio/coefficient) in two or more different survival outcomes

Suppose I'm interested in comparing smoking category (current, ex, non-smoker) as a risk factor in two or more different but similar (considerably exclusive) outcomes, say lung cancer of different ...
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Calculating Sample Size for Non-Inferiority Test in Cox Proportional Hazards Regression With Stratification

I have a binary predictor, X, in a Cox proportional hazards regression model, and I want to show that it is NOT a significant predictor. In other words, I want to show that there is not a significant ...
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Determining sample size for proportional hazard

I am in the design phase for a longitudinal study examining the effect of a predictor (neighborhood risk score) on time to an outcome (re-arrest), as well as whether or not the variation explained by ...
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Odds ratio of a continuous variable (univariate cox proportional hazards), how to plot that variable against death%?

I have a continuous variable X with which i ran Cox proportional hazards. The outcome was 1=Death, 0=censored/still alive. I have an odds ratio 0.516 for this predictor. 1) How do i interpret that ...
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What estimator to use in Cox model

I am using R/survival to analyze survival data from cancer patients. I have recently learned that there are many kinds of estimators for the Cox model, and I understand, that in theory, their order of ...
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A peer-reviewer wants more complex statistical modeling - is it reasonable?

I've submitted a manuscript to a journal and the associate editor wrote that his readers will want to know more about how the predictor of main interest (occupation) is related to death, and this will ...
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Overfitted Cox regression

I'm trying to compare the prediction abilities for death of two new biomarkers using a cohort of 173 patients. My problem is that I have only 31 outcomes and my baseline model (the one without any ...
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Cox Regression Analysis

I am trying to model the inter-arrival time between events as a survival model that depends on a set of covariates. So, I treat each event as a "death" in my model and therefore, calculate the ...
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Interpretation of interaction between covariates and time in cox regression

If I have a categorial variable (let's say $X$) and a continuos variable (let's say $Y$). IF I fitted a standard cox model, it will result in a violation of the constant HR over time (based of ...
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Is there a way to model left truncated and interval censored data in R or SAS?

We have a study where our participant underwent some surgery at time = 0, but at various ages. Our follow-up is based only on Medicare age-eligible people, so we have to wait until they reach the age ...
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Average hazard rate with Cox proportional hazard model always larger than the hazard rate without any explanatory variables?

I am estimating a Cox proportional hazard model with and without explanatory variables. Without explanatory variables, the hazard rate is just the proportion of all individuals that failed at time ...