ESTIMATION FOR THE LOCATION AND THE SCALE PARAMETERS OF THE JONES AND FADDY’S SKEW t DISTRIBUTION UNDER THE DOUBLY TYPE II CENSORED

Öz

In this study, we obtain the maximum likelihood (ML) and the modified maximum likelihood (MML) estimators for the location and the scale parameters of the Jones and Faddy’s Skew t (JFST) distribution based on the doubly Type II censored samples. Then, we use the Monte Carlo (MC) simulation study to compare the efficiencies of the ML and the MML estimators. The MC simulation study shows that, MML estimators have more or less same efficiency with the corresponding ML estimators.  At the end of the study, it can be concluded that if we focus on the efficiencies of the estimators, we prefer to use ML estimators. However, if we focus on the computational difficulties together with the efficiencies of the estimators, we prefer to use MML estimators. 

Anahtar Kelimeler

• JFST distribution,Type II censoring,Modified likelihood,Efficiency,Monte Carlo simulation

ÇİFT TARAFLI TİP II SANSÜRLENMİŞ ÖRNEKLEMLER İÇİN JONES VE FADDY’ NİN ÇARPIK t DAĞILIMININ KONUM VE ÖLÇEK PARAMETRELERİNİN TAHMİNİ

Öz

Bu çalışmada, çift taraflı Tip II sansürlenmiş (doubly Type II censored) örneklemler için Jones ve Faddy’ nin çarpık t (Jones and Faddy’ s Skew t - JFST) dağılımının konum ve ölçek parametrelerinin en çok olabilirlik (maximum likelihood - ML) ve uyarlanmış en çok olabilirlik (modified maximum likelihood - MML) tahmin edicileri elde edilmiştir. Monte Carlo (MC) simülasyon çalışması kullanılarak ML ve MML tahmin edicilerinin etkinlikleri karşılaştırılmıştır. MC simülasyon çalışması, MML tahmin edicilerinin ML tahmin edicileri ile hemen hemen aynı etkinliğe sahip olduğunu göstermiştir. Çalışma sonucunda, odaklanılan nokta tahmin edicilerin etkinlikleri ise ML tahmin edicilerinin, etkinlikle beraber hesaplama zorlukları ele alındığında ise MML tahmin edicilerinin tercih edilmesi gerektiği belirlenmiştir.

Anahtar Kelimeler

• JFST dağılımı,Tip II sansürleme,Uyarlanmış olabilirlik,Etkinlik,Monte Carlo simülasyonu

Kaynakça

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