REGRESYON ANALİZİNDE DIŞLANAN DEĞİŞKEN YANLILIĞI VE YANLILIĞIN RESET TESTİ İLE TESPİTİ

Bu çalışmada, dışlanan değişken yanlılığı, bu yanlılığın önemi, nedenleri ve sonuçları araştırılırken dışlanan değişken sorununu ortadan kaldırmak için kullanılan yöntemler incelenmiş ve ayrıca modelden dışlanan değişkenlerin varlığını saptamak üzere RESET testi kullanılmıştır. Bir benzetim çalışması yapılmıştır ve değişkenler arasındaki korelasyon değerlerine bağlı olarak değişen üç değişik tipte kitle türetilmiş ve bu kitlelerden rassal örneklemler çekilmiştir. Korelasyon değerleri değiştiğindevedışlanandeğişkensayısıarttığında dışlanan değişken yanlılığının ne gibi etkileri olduğu incelenmiştir. Ayrıca, örneklem ölçüsü arttırılarak dışlanan değişken yanlılığının örneklem ölçüsüne bağlı olarak değişip değişmediği de araştırılmıştır

OMITTED VARIABLE BIAS AND DETECTION WITH RESET TEST IN REGRESSION ANALYSIS

In this paper, it is aimed to investigate the omitted variable bias, its importance, reasons, and consequences and to research the methods for dealing with omitted variable bias and RESET test which is a method for detecting omitted variable(s). A simulation was performed and three types of populations which varied depending on the correlations between the variables were generated and random samples were drawn from these populations. When correlations were changed and the number of omitted variables was increased, the effects of omitted variable bias were investigated. Moreover, by increasing the sample size, it was investigated whether the effects of omitted variable bias were changed depending on sample size

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