Discrete Survival Time Models: An Application on Marriage Duration

Abstract

In survival analysis which is used in the social and physical sciences, it is usually assumed that the observed process is continuous. Since this assumption is not appropriate for most of the survival time data structure, survival times are measured wrongly and unreliable results are obtained for the discrete survival time data. Continuous time survival models used for the time data have represented the structure of data in the studies regarding health sciences. The usage of the discrete time survival models in social sciences is more common since the structure of the studied data is more appropriate for the discrete time models. In this study, discrete time survival models are examined theoretically and were applied to “Research on Domestic Violence against Women in Turkey, 2008” data received from Turkish Statistical Institute. In order to examine the factor effecting the duration of marriage, discrete time survival models have been used and achieved results have been interpreted.

Keywords

• Cox regression,Discrete time survival model,Logit model,Non-proportional hazards

Kesikli Yaşam Süresi Modelleri: Evlilik Süreleri Üzerine Bir Uygulama

Öz

Fen ve sosyal bilimlerde kullanılabilen yaşam modellerinde genellikle ilgilenilen sürecin sürekli olduğu varsayılmaktadır. Ancak böyle bir varsayım bazı yaşam verilerinin yapısına uygun olmadığından yaşam süreleri hatalı ölçülmekte ve kesikli yaşam süresi verileri için güvenilir olmayan sonuçlar elde edilmektedir. Sürekli veriler için kullanılan sürekli yaşam modelleri, sağlık bilimlerinde yer alan uygulamalardaki verilerin yapısını yansıtabilir. Fakat kesikli zaman verilerinin en çok kullanıldığı sosyal bilimler alanında, mevcut verilerin yapısı kesikli modellere daha uygun olduğu için özellikle bu alanda kesikli yaşam süresi modellerinin kullanımı daha yaygındır. Bu çalışmada, kesikli yaşam süresi modelleri teorik açıdan incelenmiş ve Türkiye İstatistik Kurumu’ndan alınan “Türkiye'de Kadına Yönelik Aile İçi Şiddet Araştırması, 2008” verisine uygulanmıştır. Araştırmada yer alan kadınların evli kalma sürelerine etki eden faktörlerin incelenmesinde kesikli yaşam süresi modelleri kullanılmış ve sonuçlar yorumlanmıştır.

Anahtar Kelimeler

• Cox regresyon,Kesikli yaşam süresi modelleri,Logit model,Orantısız tehlikeler

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