Volume 5, Issue 5, September 2016, Page: 290-296
Estimating Survivor Function Using Adjusted Product Limit Estimator in the Presence of Ties
Job Isaac Mukangai, Department of Statistics and Actuarial Science, Kenyatta University, Nairobi, Kenya
Leo Odiwuor Odongo, Department of Statistics and Actuarial Science, Kenyatta University, Nairobi, Kenya
Received: Jul. 21, 2016;       Accepted: Aug. 1, 2016;       Published: Aug. 21, 2016
DOI: 10.11648/j.ajtas.20160505.17      View  4345      Downloads  127
We develop an adjusted Product Limit estimator for estimating survival probabilities in the presence of ties that incorporates censored individuals using the proportion of failing for uncensored individuals. We also develop a variance estimator of the adjusted Product Limit estimator for calculating confidence intervals. Simulation studies are carried out to assess the performance of the developed estimator in comparison to the performance of Kaplan-Meier and modified Kaplan-Meier estimators. Some simulation results are presented and one real data is used for illustration. The results indicate that the proposed estimator out performs the other estimators in estimating survival probabilities in presence of ties.
Survival Analysis, Censored Data, Product Limit Estimator, Modified Kaplan-Meier
To cite this article
Job Isaac Mukangai, Leo Odiwuor Odongo, Estimating Survivor Function Using Adjusted Product Limit Estimator in the Presence of Ties, American Journal of Theoretical and Applied Statistics. Vol. 5, No. 5, 2016, pp. 290-296. doi: 10.11648/j.ajtas.20160505.17
Copyright © 2016 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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