hazard

问题 I am running cox proportional hazard regression in SPSS to see the association of 'predictor' with risk of a disease in a 10 years follow-up. I have another variable 'age_quartiles' with values 1,2,3,4 and want to use '1' as reference to get HRs for 2,3, and 4 relative to '1'. When I put this variable in Strata I still get one 'HR' as follows ('S_URAT_07' is the predictor with continuous values); Question: How do I get HRs for the predictor for the event based on 'age_quartiles' 2,3 and 4 and

问题 I consider using the lifelines package to fit a Cox-Proportional-Hazards-Model. I read that lifelines uses a nonparametric approach to fit the baseline hazard, which results in different baseline_hazards for some time points (see code example below). For my application, I need an exponential distribution leading to a baseline hazard h0(t) = lambda which is constant across time. So my question is: is it (in the meantime) possible to run a Cox-Proportional-Hazards-Model with an exponential