A simulated data set under left truncation and right censoring where censoring is always after left truncation.
The left truncation time and the event time are dependent via two covariates `Z1' and `Z2'.
Under the data generating mechanism,
the conditional distributions of the event time given covariates follows a Cox model in the full data,
and the conditional distribution of the left truncation time given covariates follows a Cox model on the reversed time scale in the full data.
The truncation rate is 29.5%; the censoring rate is 27.1%;
and the truth \(P^*(T>3) = 0.576547\).