• ISSN: 2148-2225 (online)

Ulaştırma ve Lojistik Kongreleri

alphanumeric journal

The Journal of Operations Research, Statistics, Econometrics and Management Information Systems

Outliers in Survival Analysis


Duru Karasoy, Ph.D.

Nuray Tuncer


Survival analysis is a collection of statistical methods for analyzing data where the outcome variable is the time until the occurrence of an event of interest. Outliers in survival anaysis calculated differently from classical regression analysis. Outlier detection methods in survival analysis are commonly carried out based on residuals and residual analysis. In survival analysis, there are different types of residuals that are Cox-Snell, Martingale, Schoenfeld, Deviance, Log-odds and Normal deviance residuals. There are methods which are DFBETA, LMAX and Likelihood Displacement values for detecting influential observations. The residuals are analyzed during the study which is applied on a stomach cancer data set and the outliers are detected. After omitting these outliers, model is set up again and results were found better.

Keywords: Influential Observations, Outliers, Residuals, Survival Analysis, Survival Models

Jel Classification: C10, C14, C19, C24

Yaşam Çözümlemesinde Aykırı Değerler


Yaşam çözümlemesi, tanımlanan herhangi bir olayın ortaya çıkmasına kadar geçen sürenin incelenmesinde kullanılan istatistiksel yöntemler bütünüdür. Yaşam çözümlemesinde aykırı değerler klasik regresyonda kullanılan yöntemlerden farklı yöntemler kullanılarak hesaplanmaktadır. Yaşam çözümlemesinde aykırı değer belirleme yöntemleri artıklara ve artıkların analizine dayanmaktadır. Yaşam çözümlemesinde kullanılan başlıca artık türleri Cox-Snell, Martingale, Schoenfeld, Sapma, Log-odds ve Normal sapma artıklarıdır. Etkili gözlemleri belirlemek için kullanılan yöntemler ise DFBETA, LMAX ve Olabilirlik Değişim değerleridir. İncelenen artık türleri mide kanseri ile ilgili verilere uygulanmış ve aykırı değerler belirlenmiştir. Belirlenen aykırı değerler çıkarılarak model yeniden kurulmuş ve aykırı değerler çıkarıldığında sonuçların daha iyi olduğu görülmüştür.

Anahtar Kelimeler: Artıklar, Aykırı Değerler, Etkili Gözlemler, Yaşam Modelleri, Yaşam Çözümlemesi

Suggested citation

Karasoy, D. & Tuncer, N. (). Yaşam Çözümlemesinde Aykırı Değerler. Alphanumeric Journal, 3(2), 139-152. http://dx.doi.org/10.17093/aj.2015.3.2.5000149382


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Volume 3, Issue 2, 2015


alphanumeric journal

Volume 3, Issue 2, 2015

Pages 139-152

Received: Nov. 2, 2015

Accepted: Dec. 27, 2015

Published: Dec. 31, 2015

Full Text [1.2 MB]

2015 Karasoy, D., Tuncer, N.

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