存活分析資料中的雙變數估計再近年來逐漸受到注意．在這篇論文中，我們考慮了雙變數觀察資料的情況，其中一個變數是左截取右設限，另一個變數則只有右設限．我們考慮了兩種無母數的估計方法．第一種是Satten and Datta 在2001年所提出的inverse-probability-weighted average，第二種則是Dabrowska在1988年所提的估計，並利用電腦模擬對其做比較．

Bavariate estimation with survival data has received considerable attention recently. In this paper we consider the situation of bivariate observations where one of the components is subject to left and right censoring and the other is subject to the right censoring only. Two types of nonparametric estimators are considered. The first one is the form of inverse-probability-weighted average (Satten and Datta (2001)). The second one is the generalization of Dabrowska’s (1988) estimator. The two types of estimators are then compared based on their empirical performances.

Abstract -----------------------------------------2
1 Introduction------------------------------------3
2 Inverse-Probability-Weighted Estimators---------5
3 Dabrowska''s Estimator--------------------------10
4 Simulation Results-----------------------------13
References---------------------------------------16
S-Plus Simulation Program------------------------17

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