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Survival Analysis Part II: Multivariate data analysis – an introduction to concepts and methods

M J Bradburn, T G Clark, S B Love, D G Altman
2003 British Journal of Cancer  
The method of Buckley and James (1979) for fitting linear regression models to censored data has been shown to have good statistical properties under usual regularity conditions.  ...  We conclude that the method of Buckley and James can safely be used only when the amount of censoring is small.  ...  Software We wrote a S-plus program called bj, which has been included in Frank Harrell's library Design, available at http://hesweb1.med.virginia.edu/biostat/s/win/.  ... 
doi:10.1038/sj.bjc.6601119 pmid:12888808 pmcid:PMC2394368 fatcat:xjhlwo5m65httjorwgqpyuwmoe

LSS: An S-Plus/R program for the accelerated failure time model to right censored data based on least-squares principle

Lin Huang, Zhezhen Jin
2007 Computer Methods and Programs in Biomedicine  
model is seldom used in practice for the analysis of right censored data.  ...  The program is user-friendly and yields outputs similar to S-Plus/R function 1m.  ...  Acknowledgement This research was supported in part by the National Science Foundation career award DMS-0134431. We thank the two anonymous reviewers for helpful comments.  ... 
doi:10.1016/j.cmpb.2006.12.005 pmid:17250925 fatcat:xg7tnrccbrdlhlkdon6id64rji

Buckley-James Boosting for Survival Analysis with High-Dimensional Biomarker Data

Zhu Wang, C.Y. Wang
2010 Statistical Applications in Genetics and Molecular Biology  
We propose the Buckley-James boosting for the semiparametric accelerated failure time models with right censored survival data, which can be used to predict survival of future patients using the high-dimensional  ...  The proposed methods have a unified approach to fit linear models, non-linear effects models with possible interactions.  ...  Finally, it will be demonstrated that the Buckley-James (BJ) estimation (Buckley and James, 1979) for the AFT model can be conveniently extended to describe more complex data structures with existing  ... 
doi:10.2202/1544-6115.1550 pmid:20597850 pmcid:PMC2904263 fatcat:hwz7ybzgf5f37fpufq2dtmm6je

Latent Subgroup Analysis of a Randomized Clinical Trial through a Semiparametric Accelerated Failure Time Mixture Model

L. Altstein, G. Li
2013 Biometrics  
We derive a computational method to estimate model parameters by iterating between an expectation step and a weighted Buckley-James optimization step.  ...  The bootstrap method is used for variance estimation, and the performance of our method is corroborated in simulation.  ...  Louis, the editor, an Associate Editor, and a referee for their insightful and constructive comments that led to significant improvements of the paper. We also thank Drs. R. Elashoff and D.L.  ... 
doi:10.1111/j.1541-0420.2012.01818.x pmid:23383608 pmcid:PMC3622121 fatcat:xg2doc5lubh2pkdvqmzu4ds35e

"Smooth" Semiparametric Regression Analysis for Arbitrarily Censored Time-to-Event Data

Min Zhang, Marie Davidian
2008 Biometrics  
A general framework for regression analysis of time-to-event data subject to arbitrary patterns of censoring is proposed.  ...  The utility and performance of the methods are demonstrated via simulations and by application to data from time-to-event studies.  ...  The authors gratefully acknowledge the comments of the co-editor, associate editor, and two reviewers, which led to improvements to the paper and Supplementary Materials.  ... 
doi:10.1111/j.1541-0420.2007.00928.x pmid:17970813 pmcid:PMC2575078 fatcat:v5nrshgt7nfzxbrjh5mrnni47m

Semiparametric Bayesian analysis of censored linear regression with errors-in-covariates

Samiran Sinha, Suojin Wang
2015 Statistical Methods in Medical Research  
In this paper we consider fitting an AFT model to right censored data when a predictor variable is subject to measurement errors.  ...  Accelerated failure time (AFT) model is a well known alternative to the Cox proportional hazard model for analyzing time-to-event data.  ...  Acknowledgments The authors gratefully acknowledge the constructive comments from the referees that led to a significant improvement of the manuscript.  ... 
doi:10.1177/0962280215580668 pmid:25882297 fatcat:ua5m27p5yzgblec5izg5o6ex3q

Applying nomograms based on the surveillance, epidemiology and end results database to predict long-term overall survival and cancer-specific survival in patients with oropharyngeal squamous cell carcinomas

Fengze Wang, Jiao Wen, Xinjie Yang, Tingting Jia, Fangchong Du, Jianhua Wei
2020 Medicine  
We developed 2 nomograms to predict 5- and 8- year OS and CSS using Cox Proportional Hazards model.  ...  Furthermore, we applied a popular and reasonable random split-sample method to divide the total 10,980 patients into 2 groups, including 9881 (90%) patients in the modeling cohort and 1099 (10%) patients  ...  ="Buckley-James Censored Data Regression", ...) ## S3 method for class bj residuals(object, type=c("censored","censored.normalized"),...) bjplot(fit, which=1:dim(X) [[2] ]) ## S3 method for class bj validate  ... 
doi:10.1097/md.0000000000020703 pmid:32791664 pmcid:PMC7386992 fatcat:6vaqxcx7gjflvp6ffarqh4rnxu

POSSIBLE CONSTRAINTS ON EXOPLANET MAGNETIC FIELD STRENGTHS FROM PLANET-STAR INTERACTION

Caleb A. Scharf
2010 Astrophysical Journal  
The high-energy photon emission of planet-star systems may therefore provide unique access to the detailed magnetic, and hence geodynamic, properties of exoplanets.  ...  A small percentage of normal stars harbor giant planets that orbit within a few tenths of an astronomical unit.  ...  We fit for a power law correlation in both samples using a Buckley-James (BJ) regression with Kaplan-Meier residuals (a more restrictive EM algorithm fit yields essentially identical results in all cases  ... 
doi:10.1088/0004-637x/722/2/1547 fatcat:2jcnnfpehraojlo3umdgm62p3e

Public health interpretation of trihalomethane blood levels in the United States: NHANES 1999–2004

Judy S Lakind, Daniel Q Naiman, Sean M Hays, Lesa L Aylward, Benjamin C Blount
2009 Journal of Exposure Science and Environmental Epidemiology  
Buckley-James least squares model for censored data survreg The following functions have special meaning when using Design.  ...  survival models in the accelerated failure time class 5. Buckley-James distribution-free regression model for right-censored responses 6.  ...  Chapter 8 Builtin S Functions for Multiple Linear Regression lm is the builtin function for fitting multiple linear regression models, and it works with several other functions to summarize results, make  ... 
doi:10.1038/jes.2009.35 pmid:19550438 fatcat:crpmkmo4vbab3jgxepkmjgtoaa

A QUASAR CATALOG WITH SIMULTANEOUS UV, OPTICAL, AND X-RAY OBSERVATIONS BYSWIFT

Jian Wu, Daniel Vanden Berk, Dirk Grupe, Scott Koch, Jonathan Gelbord, Donald P. Schneider, Caryl Gronwall, Sarah Wesolowski, Blair L. Porterfield
2012 Astrophysical Journal Supplement Series  
From model fits to these SEDs, we find that the big blue bump contributes about 0.3 dex to the quasar luminosity.  ...  We re-visit the alpha_ox-L_uv relation by selecting a clean sample with only type 1 radio-quiet quasars; the dispersion of this relation is reduced by at least 15% compared to studies that use non-simultaneous  ...  This package includes the Expectation-Maximization (EM; Dempster et al. 1977 ) and the Buckley-James (BJ; Buckley & James 1979) algorithms, which we can use to perform linear regression and dispersion  ... 
doi:10.1088/0067-0049/201/2/10 fatcat:yz55ysgxibebri7xg2bz7zrjza

The Low End of the Supermassive Black Hole Mass Function: Constraining the Mass of a Nuclear Black Hole in NGC 205 via Stellar Kinematics

Monica Valluri, Laura Ferrarese, David Merritt, Charles L. Joseph
2005 Astrophysical Journal  
We are unable to identify a best-fit value of M_BH in NGC 205; however, the data impose a upper limit of 2.2x10^4 M_sun (1sigma confidence) and and upper limit of 3.8x10^4 M_sun (3sigma confidence).  ...  We use our 3-integral models to evaluate the relaxation time (T_r) and stellar collision time (T_coll) in NGC 205; T_r~10^8 yr or less in the nucleus and T_coll~10^11 yr.  ...  Two censored regression methods are in wide use: the EM algorithm (Dempster, Laird & Rubin 1977) , a maximum likelihood method that assumes a normal distribution of the ordinate values about the best-fit  ... 
doi:10.1086/430752 fatcat:nyhlzdaw4zc5zenox6bnupfsmi