GENERALIZED SOBEL TEST WITH ROBUST STANDARD ERRORS FOR STATISTICAL VALIDATION OF SERIAL MEDIATION EFFECTS ON EDUCATIONAL AND PSYCHOLOGICAL RESEARCH
Received: 29th July 2024 Revised: 22nd August 2024, 3rd September 2024 Accepted: 11th August 2024
Keywords:
Sobel Test, Robust Standard Error, Serial Mediation, Indirect Effect Test, Bootstrap TestAbstract
A serial mediation effect refers to a mediation effect that emerges through multiple stages within a mediation model, such as 'X->M1->M2 ->...-> Y'. Recently, high-performance PCs have enabled the application of the Bootstrap technique to obtain confidence intervals and determine statistical significance. However, when raw data is unavailable or when attempting to calculate mediation effects from other studies, the Sobel test can be utilized. Yet, the calculation of the Sobel test’s standard error becomes complex when there are more than three coefficients in a path, highlighting the need for a dedicated computational tool. Additionally, when the sample size is small, adjustments for normal distribution and heteroscedasticity issues are required. Consequently, this study proposes a method for calculating the standard error of the generalized Sobel test and introduces a calculator that implements this method.
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