Springer Publishing

If there were 3 deaths out of 10 at risk, then the first increments the hazard by 3/10 and the second by 1/10 + 1/9 + 1/8. For the first method S(t) = exp(H), where H is the Nelson–Aalen cumulative hazard estimate, whereas the fh2 method will give S(t) results closer to the K–M estimate. ................
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