English  |  正體中文  |  简体中文  |  Items with full text/Total items : 43312/67235
Visitors : 2169472      Online Users : 18
RC Version 5.0 © Powered By DSPACE, MIT. Enhanced by NTU/NCHU Library IR team.

Please use this identifier to cite or link to this item: http://nchuir.lib.nchu.edu.tw/handle/309270000/133576

標題: Heterogeneity and varying effect in hazards regression
作者: Wu, H.D.I.;Hsieh, F.S.
關鍵字: Proportional hazards;Varying coefficient;Nonproportional hazards;Multiple crossings;Heterogeneity;time-dependent coefficients;censored-data;model
日期: 2009
Issue Date: 2012-12-14 10:05:14 (UTC+8)
關連: Journal of Statistical Planning and Inference, Volume 139, Issue 12, Page(s) 4213-4222.
摘要: In the analysis of survival data, when nonproportional hazards are encountered, the Cox model is often extended to allow for a time-dependent effect by accommodating a varying coefficient. This extension, however, cannot resolve the nonproportionality caused by heterogeneity. In contrast, the heteroscedastic hazards regression (HHR) model is capable of modeling heterogeneity and thus can be applied when dealing with nonproportional hazards. In this paper, we study the application of the HHR model possibly equipped with varying coefficients. An LRR (logarithm of relative risk) plot is suggested when investigating the need to impose varying coefficients. Constancy and degeneration in the plot are used as diagnostic criteria. For the HHR model, a 'piecewise effect' (PE) analysis and an 'average effect' (AE) analysis are introduced. For the PE setting, we propose a score-type test for covariate-specific varying coefficients. The Stanford Heart Transplant data are analyzed for illustration. In the case of degeneration being destroyed by a polynomial covariate, piecewise constancy and/or monotonicity of the LRRs is considered as an alternative criterion based on the PE analysis. Finally, under the framework of the varying-coefficient HHR model, the meanings of the PE and AE analyses, along with their dynamic interpretation, are discussed. (C) 2009 Elsevier B.V. All rights reserved.
Relation: Journal of Statistical Planning and Inference
Appears in Collections:[依資料類型分類] 期刊論文
[依教師分類] 吳宏達
[依教師分類] 吳宏達

loading Web of Knowledge data....

Files in This Item:

File SizeFormat






聯絡網站維護人員:wyhuang@nchu.edu.tw,04-22840290 # 412。

DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU/NCHU Library IR team Copyright ©   - Feedback