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Bagging survival trees.

Torsten Hothorn·Berthold Lausen·Axel Benner·Martin Radespiel-Tröger
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Abstract

Predicted survival probability functions of censored event free survival are improved by bagging survival trees. We suggest a new method to aggregate survival trees in order to obtain better predictions for breast cancer and lymphoma patients. A set of survival trees based on B bootstrap samples is computed. We define the aggregated Kaplan-Meier curve of a new observation by the Kaplan-Meier curve of all observations identified by the B leaves containing the new observation. The integrated Brier score is used for the evaluation of predictive models. We analyse data of a large trial on node positive breast cancer patients conducted by the German Breast Cancer Study Group and a smaller 'pilot' study on diffuse large B-cell lymphoma, where prognostic factors are derived from microarray expression values. In addition, simulation experiments underline the predictive power of our proposal.

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Breast NeoplasmsClinical Trials as TopicFemaleGermanyHumansLymphomaMaleModels, StatisticalSurvival AnalysisCommentJournal Article

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BibTeXRIS

Torsten Hothorn, Berthold Lausen, Axel Benner, Martin Radespiel-Tröger. 2004-01-15. Bagging survival trees.. https://doi.org/10.1002/sim.1593

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