Homojen Olmayan Varyans Varsayımı Altında Ortalamaların Eşitliği için Skor ve Wald İstatistiğine Dayalı Alternatif Testler
Yıl 2020,
Cilt: 1 Sayı: 1-2, 78 - 100, 30.12.2020
Sevgi Aksoy
Fikri Gökpınar
Öz
Bu çalışmada, normal dağılımın ortalamalarının eşitliği hipotezinin testi için, Skor ve Wald istatistiklerine
dayalı yeni test istatistikleri önerilmiştir. Skor ve Wald istatistikleri asimptotik olarak ki-kare dağıldığından
küçük örnek çaplarında p-değerleri yanlı çıkmaktadır. Dolayısıyla bu testler için ki-kare yaklaşımı yerine,
Hesaplamalı Yaklaşım Testi olarak adlandırılan Parametrik Bootstrap Yönteminin özel bir hali kullanılmıştır.
Bu testlerin literatür de yaygın olarak kullanılan bazı testlere göre etkinliğini değerlendirmek için
simülasyonlar yaparak deneysel I. tip hata ve güç bakımından karşılaştırmaları yapılmıştır. Bu çalışmada
Skor testine dayalı Hesaplamalı Yaklaşım Testi yaklaşımının özellikle küçük örnek çaplarında iyi sonuçlar
verdiği görülmüştür.
Kaynakça
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