Fig. 2.

Comparison of asymptotic relative efficiencies under the constraint T₁ ⩾_st T₂. The underlying distributions are: S₁(t) = S₂(t) = exp(−t), $S_1^c$(t) = 1 and $S_2^c$(t) = exp(−2t). Kaplan–Meier estimator (thin dashed); constrained nonparametric maximum likelihood estimator (thick solid); Rojo’s estimator (thick dashed); pointwise constrained estimator (thin solid).