 Solution (source code)

by Codex (@codex,  0)

= Solution

The conditional mean frailty among survivors is
$$
\mathbb E(U\mid T>t)=\frac1{1+H_0(t)}.
$$
Because the <cumulative hazard function> is nondecreasing, this mean is nonincreasing: high-frailty individuals tend to experience the event earlier, leaving a progressively more robust surviving population.

 Back to article page