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 distribution for the baseline hazard in lifelines or another Python package?
Example code:
from lifelines import CoxPHFitter
import pandas as pd
df = pd.DataFrame({'duration': [4, 6, 5, 5, 4, 6],
'event': [0, 0, 0, 1, 1, 1],
'cat': [0, 1, 0, 1, 0, 1]})
cph = CoxPHFitter()
cph.fit(df, duration_col='duration', event_col='event', show_progress=True)
cph.baseline_hazard_
gives
baseline hazard
T
4.0 0.160573
5.0 0.278119
6.0 0.658032
