TY - JOUR T1 - Bir-Yönlü Kovaryans Analizinde Parametrelerin RAMML Yöntemi ile Tahmini TT - Estimation of the Parameters in One-Way Analysis of Covariance with the RAMML Method AU - Acıtaş, Şükrü PY - 2025 DA - June Y2 - 2025 DO - 10.33484/sinopfbd.1644300 JF - Sinop Üniversitesi Fen Bilimleri Dergisi JO - Sinop Uni J Nat Sci PB - Sinop Üniversitesi WT - DergiPark SN - 2536-4383 SP - 188 EP - 199 VL - 10 IS - 1 LA - tr AB - Deney tasarımında temel amaç, ilgilenilen faktörün düzeyleri olarak tanımlanan denemelerin ortalamaları arasında istatistiksel olarak anlamlı bir farklılık olup olmadığının belirlenmesidir. Yanıt değişkeni (y) üzerinde kontrol edilebilen faktörün etkisinin yanı sıra bazı durumlarda kontrol edilemeyen ortak değişkenin de etkisi söz konusu olabilir. Bu durumda, deneysel hatayı azaltmak amacıyla kontrol edilemeyen ortak değişkenin yanıt değişkeni üzerindeki etkisi arındırılarak analizin yapılması gerekir. Bu amaçla, kontrol edilemeyen ortak değişken (x) modele dahil edilir. Bu yöntem, deney tasarımında kovaryans analizi (analysis of covariance – ANCOVA) olarak adlandırılır. Varyans analizi ile regresyon analizi tekniklerinin bir birleşimi olarak ifade edilen ANCOVA hem y-yönlü hem de x-yönlü aykırı değerlere karşı duyarlıdır. Literatürde y-yönlü aykırı değerlere karşı dayanıklı ANCOVA ile ilgili çalışmalar bulunmasına rağmen bilindiği kadarıyla x-yönlü aykırı değerlere karşı dayanıklı adaptif uyarlanmış en çok olabilirlik (robust adaptive modified maximum likelihood – RAMML) tahmin edicilerine dayanan ANCOVA bağlamında herhangi bir çalışma bulunmamaktadır. Bu çalışmada, y-yönlü aykırı değerlere ek olarak ortak değişkende aykırı değerler olması, bir başka ifade ile x-yönlü aykırı değerler olması durumu ele alınmış ve bir-yönlü ANCOVA’da model parametrelerinin RAMML tahmin edicileri elde edilmiştir. 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