İki Bağımlı Korelasyon Katsayısı Karşılaştırma Testlerinin Performansları için Simülasyon Çalışması ve Akut Apandisit Verileri Üzerinde Bir Uygulama

Abstract

Objective: Although it is frequently encountered in many studies to examine the relationships between different features of the individuals by using correlation coefficient, it is a situation that can be ignored to statistically test whether there is a difference between the correlation coefficients obtained. In this study, it is aimed to compare the performances of statistical tests proposed for the comparison of dependent overlapping correlation coefficients, in terms of their Type I error rates, within the framework of a wide simulation scenario. Material and Methods: The 6 test procedures were compared with a simulation study, conducted at 5 different intercorrelation magnitudes, with 5 different null correlation coefficient magnitudes, at 6 different sample sizes. Results: Pearson and Filon's z (PF) test performed poorly compared to other 5 procedures in most cases. For small intercorrelation magnitudes Steiger's modification of Dunn and Clark's z (SM) test, Meng, Rosenthal, and Rubin's z (MRR) test, Rosenthal, and Rubin's z test, Hittner, May, and Silver's modification of Dunn and Clark's z (HMS) test and ZOU's approach for overlapping correlations (ZA) procedures outperformed PF test and Hendrickson, Stanley, and Hills' modification of Williams't test (HSHM) especially in small to moderate sample sizes. For larger intercorrelation coefficients, HSHM test gave better results in small to moderate sample sizes and ZA procedure maintained its superiority at the 0.7 intercorrelation level. Conclusion: Tests' performances in terms of Type I error are affected from the magnitude of null correlation, magnitude of intercorrelation and sample size, in different ways. It will be helpful to consider these issues when selecting the appropriate statistical test.