Bathtub hazard model with covariate and right censored data

Lifetime distributions that present bathtub-shaped failure rates are becoming increasingly important especially when dealing with medical data. In this research, a two-parameter bathtub hazard model was extended to incorporate covariates in the presence of right censored data. The parameter estimate...

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Main Authors: Ismail, Idari, Arasan, Jayanthi, Mustafa, Mohd Shafie, Mohd Safari, Muhammad Aslam
Format: Article
Published: Universiti Kebangsaan Malaysia 2022
Online Access:http://psasir.upm.edu.my/id/eprint/100515/
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author Ismail, Idari
Arasan, Jayanthi
Mustafa, Mohd Shafie
Mohd Safari, Muhammad Aslam
author_facet Ismail, Idari
Arasan, Jayanthi
Mustafa, Mohd Shafie
Mohd Safari, Muhammad Aslam
author_sort Ismail, Idari
building UPM Institutional Repository
collection Online Access
description Lifetime distributions that present bathtub-shaped failure rates are becoming increasingly important especially when dealing with medical data. In this research, a two-parameter bathtub hazard model was extended to incorporate covariates in the presence of right censored data. The parameter estimates were computed based on maximum likelihood estimation (MLE) method. A simulation study was then executed to assess the performance of parameter estimates based on their bias, standard error (SE) and root mean square error (RMSE) at various censoring proportions and sample sizes. The results suggested that the performance of the estimator is better at larger sample size as it lower the standard error and root mean square error (RMSE). A decrease in censoring proportions yield smaller SE and RMSE values, whereas the values of bias decrease as the sample sizes and censoring proportions increase. Finally, the extended model was applied to a real medical data. Also, three confidence interval estimation (Wald, bootstrap-p, bootstrap-t) were obtained for each of the parameters of the model. The results suggested that the real data fitted the bathtub hazard model well.
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institution Universiti Putra Malaysia
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publisher Universiti Kebangsaan Malaysia
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spelling upm-1005152023-11-21T08:29:43Z http://psasir.upm.edu.my/id/eprint/100515/ Bathtub hazard model with covariate and right censored data Ismail, Idari Arasan, Jayanthi Mustafa, Mohd Shafie Mohd Safari, Muhammad Aslam Lifetime distributions that present bathtub-shaped failure rates are becoming increasingly important especially when dealing with medical data. In this research, a two-parameter bathtub hazard model was extended to incorporate covariates in the presence of right censored data. The parameter estimates were computed based on maximum likelihood estimation (MLE) method. A simulation study was then executed to assess the performance of parameter estimates based on their bias, standard error (SE) and root mean square error (RMSE) at various censoring proportions and sample sizes. The results suggested that the performance of the estimator is better at larger sample size as it lower the standard error and root mean square error (RMSE). A decrease in censoring proportions yield smaller SE and RMSE values, whereas the values of bias decrease as the sample sizes and censoring proportions increase. Finally, the extended model was applied to a real medical data. Also, three confidence interval estimation (Wald, bootstrap-p, bootstrap-t) were obtained for each of the parameters of the model. The results suggested that the real data fitted the bathtub hazard model well. Universiti Kebangsaan Malaysia 2022-11 Article PeerReviewed Ismail, Idari and Arasan, Jayanthi and Mustafa, Mohd Shafie and Mohd Safari, Muhammad Aslam (2022) Bathtub hazard model with covariate and right censored data. Journal of Quality Measurement and Analysis, 18 (3). pp. 1-15. ISSN 2600-8602 https://www.ukm.my/jqma/jqma18-3/
spellingShingle Ismail, Idari
Arasan, Jayanthi
Mustafa, Mohd Shafie
Mohd Safari, Muhammad Aslam
Bathtub hazard model with covariate and right censored data
title Bathtub hazard model with covariate and right censored data
title_full Bathtub hazard model with covariate and right censored data
title_fullStr Bathtub hazard model with covariate and right censored data
title_full_unstemmed Bathtub hazard model with covariate and right censored data
title_short Bathtub hazard model with covariate and right censored data
title_sort bathtub hazard model with covariate and right censored data
url http://psasir.upm.edu.my/id/eprint/100515/
http://psasir.upm.edu.my/id/eprint/100515/