Does Statistical Power Affect a Study’s Results? How Many Sample Size?

Öz

The statistical power analysis is a method that enables to plan a highly valid and reliable research and to guarantee the validity, reliability and sensibility of the results of a research. Statistical power is an approach which is used to evaluate to what degree the decisions obtained as a result of statistical tests used to test an aim are valid and reliable in terms of probability values. Various statistical analyses begin the analysis with the existing data and focus on the comments of the consequences. Nevertheless, power analysis is meaningful before data collection and significant in the process of setting the hypothesis. In this context, the major purposes of this study are; to contribute researches in social sciences by creating awareness about what the power analysis means and to guide researchers about how the power analyses can be employed in a social science study.

İstatistiksel Güç Bir Araştırmanın Sonuçlarına Etki Eder Mi? Örneklem Büyüklüğüne Nasıl Karar Verilmeli?

Öz

İstatistiksel güç analizi; güvenilirliği, geçerliliği yüksek bir araştırma planlamayı ve araştırma sonucunda alınacak kararların geçerliliğini, güvenilirliğini ve duyarlılığını garanti altına almayı sağlayan bir yöntemdir. İstatistiksel güç, araştırmada bir hipotezin denetlenmesi için kullanılan istatistiksel testler sonucunda varılan kararın ne kadar güvenilir ve geçerli olduğunu olasılık olarak tahmin eden bir yaklaşımdır. Güç analizi, diğer istatistiksel yaklaşımlardan önemli ölçüde farklıdır. Birçok istatistiksel analiz mevcut veri ile analize başlamakta ve sonuçların yorumuna odaklanmaktadır. Hâlbuki güç analizi daha çok veri toplama öncesinde anlamlıdır ve hipotez kurma sürecinde önemlidir. Bu bağlamda çalışmanın amacı, sosyal bilim çalışmalarında istatistiksel güç analizinin ne olduğu konusunda farkındalık oluşturarak araştırmalara katkı sağlamak ve bir araştırmada istatistiksel güç analizinin nasıl kullanılacağı konusunda araştırmacılara rehberlik etmektir.

Anahtar Kelimeler

• İstatistiksel Güç
• İstatistiksel Güç Analizi
• Etki Büyüklüğü

Kaynakça

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